Separations

12 pages, 2529 KiB

Open AccessArticle

NanoMIP-Based Solid Phase Extraction of Fluoroquinolones from Human Urine: A Proof-of-Concept Study

by Matteo Chiarello, Laura Anfossi, Simone Cavalera, Fabio Di Nardo, Thea Serra and Claudio Baggiani

Separations 2021, 8(11), 226; https://doi.org/10.3390/separations8110226 - 19 Nov 2021

Cited by 8 | Viewed by 2897

Abstract

NanoMIPs that are prepared by solid phase synthesis have proven to be very versatile, but to date only limited attention has been paid to their use in solid phase extraction. Thus, since nanoMIPs show close similarities, in terms of binding behavior, to antibodies, [...] Read more.

NanoMIPs that are prepared by solid phase synthesis have proven to be very versatile, but to date only limited attention has been paid to their use in solid phase extraction. Thus, since nanoMIPs show close similarities, in terms of binding behavior, to antibodies, it seems relevant to verify if it is possible to use them as mimics of the natural antibodies that are used in immunoextraction methods. As a proof-of-concept, we considered prepared nanoMIPs against fluoroquinolone ciprofloxacin. Several nanoMIPs were prepared in water with polymerization mixtures of different compositions. The polymer with the highest affinity towards ciprofloxacin was then grafted onto a solid support and used to set up a solid phase extraction–HPLC method with fluorescence detection, for the determination of fluoroquinolones in human urine. The method resulted in successful selection for the fluoroquinolone antibiotics, such that the nanoMIPs were suitable for direct extraction of the antibiotics from the urine samples at the µg mL⁻¹ level. They required no preliminary treatment, except for a 1 + 9 (v/v) dilution with a buffer of pH 4.5 and they had good analyte recovery rates; up to 85% with precision in the range of 3 to 4.5%, without interference from the matrix. These experimental results demonstrate, for the first time, the feasibility of the use of nanoMIPs to develop solid phase extraction methods. Full article

(This article belongs to the Special Issue Molecularly Imprinted Polymers: Selective Extraction Materials for Sample Preparation)

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17 pages, 4305 KiB

Open AccessArticle

Study on the Preparation of Magnetic Mn–Co–Fe Spinel and Its Mercury Removal Performance

by Jiawei Huang, Zhaoping Zhong, Yueyang Xu and Yuanqiang Xu

Separations 2021, 8(11), 225; https://doi.org/10.3390/separations8110225 - 19 Nov 2021

Cited by 7 | Viewed by 2645

Abstract

In this study, the manganese-doped manganese–cobalt–iron spinel was prepared by the sol–gel self-combustion method, and its physical and chemical properties were analyzed by XRD (X-ray diffraction analysis), SEM (scanning electron microscope), and VSM (vibrating sample magnetometer). The mercury removal performance of simulated flue [...] Read more.

In this study, the manganese-doped manganese–cobalt–iron spinel was prepared by the sol–gel self-combustion method, and its physical and chemical properties were analyzed by XRD (X-ray diffraction analysis), SEM (scanning electron microscope), and VSM (vibrating sample magnetometer). The mercury removal performance of simulated flue gas was tested on a fixed bed experimental device, and the effects of Mn doping amount, fuel addition amount, reaction temperature, and flue gas composition on its mercury removal capacity were studied. The results showed that the best synthesized product was when the doping amount of Mn was the molar ratio of 0.5, and the average mercury removal efficiency was 87.5% within 120 min. Among the fuel rich, stoichiometric ratio, and fuel lean systems, the stoichiometric ratio system is most conductive to product synthesis, and the mercury removal performance of the obtained product was the best. Moreover, the removal ability of Hg⁰ was enhanced with the increase in temperature in the test temperature range, and both physical and chemical adsorption play key roles in the spinel adsorption of Hg⁰ in the medium temperature range. The addition of O₂ can promote the removal of Hg⁰ by adsorbent, but the continuous increase after the volume fraction reached 10% had little effect on the removal efficiency of Hg⁰. While SO₂ inhibited the removal of mercury by adsorbent, the higher the volume fraction, the more obvious the inhibition. In addition, in an oxygen-free environment, the addition of a small amount of HCl can promote the removal of mercury by adsorbent, but the addition of more HCl does not have a better promotion effect. Compared with other reported adsorbents, the adsorbent has better mercury removal performance and magnetic properties, and has a strong recycling performance. The removal efficiency of mercury can always be maintained above 85% in five cycles. Full article

(This article belongs to the Special Issue Development and Application of Green or Sustainable Strategies in Analytical Chemistry)

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18 pages, 3387 KiB

Open AccessArticle

Gum Arabic-Magnetite Nanocomposite as an Eco-Friendly Adsorbent for Removal of Lead(II) Ions from Aqueous Solutions: Equilibrium, Kinetic and Thermodynamic Studies

by Ismat H. Ali, Mutasem Z. Bani-Fwaz, Adel A. El-Zahhar, Riadh Marzouki, Mosbah Jemmali and Sara M. Ebraheem

Separations 2021, 8(11), 224; https://doi.org/10.3390/separations8110224 - 18 Nov 2021

Cited by 12 | Viewed by 3016

Abstract

In this study, a gum Arabic-magnetite nanocomposite (GA/MNPs) was synthesized using the solution method. The prepared nanocomposite was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and thermogravimetric analysis [...] Read more.

In this study, a gum Arabic-magnetite nanocomposite (GA/MNPs) was synthesized using the solution method. The prepared nanocomposite was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). The prepared composite was evaluated for the adsorption of lead(II) ions from aqueous solutions. The controlling factors such as pH, contact time, adsorbent dose, initial ion concentration, and temperature were investigated. The optimum adsorption conditions were found to be 0.3 g/50 mL, pH = 6.00, and contact time of 30 min. The experimental data well fitted the pseudo-second-order kinetic model and the Langmuir isotherm model. The maximum adsorption capacity was determined as 50.5 mg/g. Thermodynamic parameters were calculated postulating an endothermic and spontaneous process and a physio-sorption pathway. Full article

(This article belongs to the Special Issue Development and Application of Green or Sustainable Strategies in Analytical Chemistry)

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16 pages, 2075 KiB

Open AccessArticle

Plant Growth-Promoting Rhizobacteria Modulate the Concentration of Bioactive Compounds in Tomato Fruits

by Clara de la Osa, Miguel Ángel Rodríguez-Carvajal, Jacinto Gandullo, Clara Aranda, Manuel Megías, Francisco Javier Ollero, Francisco Javier López-Baena and José Antonio Monreal

Separations 2021, 8(11), 223; https://doi.org/10.3390/separations8110223 - 18 Nov 2021

Cited by 3 | Viewed by 3046

Abstract

Background: The application of microorganisms as bioestimulants in order to increase the yield and/or quality of agricultural products is becoming a widely used practice in many countries. In this work, five plant growth-promoting rhizobacteria (PGPR), isolated from cultivated rice paddy soils, were [...] Read more.

Background: The application of microorganisms as bioestimulants in order to increase the yield and/or quality of agricultural products is becoming a widely used practice in many countries. In this work, five plant growth-promoting rhizobacteria (PGPR), isolated from cultivated rice paddy soils, were selected for their plant growth-promoting capacities (e.g., auxin synthesis, chitinase activity, phosphate solubilisation and siderophores production). Two different tomato cultivars were inoculated, Tres Cantos and cherry. Plants were grown under greenhouse conditions and different phenotypic characteristics were analysed at the time of harvesting. Results: Tres Cantos plants inoculated with PGPR produced less biomass but larger fruits. However, the photosynthetic rate was barely affected. Several antioxidant activities were upregulated in these plants, and no oxidative damage in terms of lipid peroxidation was observed. Finally, ripe fruits accumulated less sugar but, interestingly, more lycopene. By contrast, inoculation of cherry plants with PGPR had no effect on biomass, although photosynthesis was slightly affected, and the productivity was similar to the control plants. In addition, antioxidant activities were downregulated and a higher lipid peroxidation was detected. However, neither sugar nor lycopene accumulation was altered. Conclusion: These results support the use of microorganisms isolated from agricultural soils as interesting tools to manipulate the level of important bioactive molecules in plants. However, this effect seems to be very specific, even at the variety level, and deeper analyses are necessary to assess their use for specific applications. Full article

(This article belongs to the Special Issue Separation and Determination of Food's Bioactive Compounds Content Changes in Different Culture Conditions and Post-harvest Practices)

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8 pages, 616 KiB

Open AccessArticle

HILIC-MS/MS Analysis of Adenosine in Patient Blood

by Christina Virgiliou, Nikolaos Fragakis, Melani Sotiriadou, Vassilios Vassilikos, Spiros Gerou, Georgios Theodoridis and Helen Gika

Separations 2021, 8(11), 222; https://doi.org/10.3390/separations8110222 - 17 Nov 2021

Cited by 5 | Viewed by 3436

Abstract

Adenosine is a purine ribonucleoside with important roles in various physiological processes. A number of studies have indicated the importance of adenosine in cardiovascular diseases including syncope; however, the accurate determination of adenosine in human blood is challenging due to the molecule’s instability. [...] Read more.

Adenosine is a purine ribonucleoside with important roles in various physiological processes. A number of studies have indicated the importance of adenosine in cardiovascular diseases including syncope; however, the accurate determination of adenosine in human blood is challenging due to the molecule’s instability. In the present study, we report a simple method for the pre-treatment of blood samples and the development of a fast and efficient hydrophilic interaction chromatographic tandem mass spectrometry method for the analysis of adenosine in patient blood. During collection, samples were mixed directly with a solvent mixture containing 95% acetonitrile and 10 mM ammonium formate in a Vacutainer tube, resulting in successful prevention of adenosine metabolic processes and direct blood sample deproteinization. The method was validated according to bioanalytical industry guidelines and found to be accurate, repeatable, specific and sensitive with LLOQ 0.005 μg/mL, thus allowing its application in the analysis of real clinical samples. Full article

(This article belongs to the Special Issue Application of Separations Technologies in Biomedical Analysis)

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18 pages, 1144 KiB

Open AccessEditor’s ChoiceArticle

Development of a New LC-MS/MS Screening Method for Detection of 120 NPS and 43 Drugs in Blood

by Fabio Vaiano, Elisabetta Bertol, Maria Mineo, Laura Pietrosemoli, Jolanda Rubicondo, Claudiu T. Supuran and Fabrizio Carta

Separations 2021, 8(11), 221; https://doi.org/10.3390/separations8110221 - 17 Nov 2021

Cited by 13 | Viewed by 7436

Abstract

In the last few years, liquid chromatography coupled with mass spectrometry (LC/MS) has been increasingly used for screening purposes in forensic toxicology. These techniques have the advantages of low time/resource-consuming and high versatility and have been applied in numerous new multi-analytes methods. The [...] Read more.

In the last few years, liquid chromatography coupled with mass spectrometry (LC/MS) has been increasingly used for screening purposes in forensic toxicology. These techniques have the advantages of low time/resource-consuming and high versatility and have been applied in numerous new multi-analytes methods. The new psychoactive substance (NPS) phenomenon provided a great impulse to this wide-range approach, but it is also important to keep the attention on “classical” psychoactive substances, such as benzodiazepines (BDZ). In this paper, a fully validated screening method in blood for the simultaneous detection of 163 substances (120 NPS and 43 other drugs) by a dynamic multiple reaction monitoring analysis through LC-MS/MS is described. The method consists of a deproteinization of 200 µL of blood with acetonitrile. The LC separation is achieved with a 100 mm long C18 column in 35 min. The method was very sensitive, with limits of quantification from 0.02 to 1.5 ng/mL. Matrix effects did not negatively affect the analytical sensitivity. This method proved to be reliable and was successfully applied to our routinary analytical activity in several forensic caseworks, allowing the identification and quantification of many BDZs and 3,4-methylenedioxypyrovalerone (MDPV). Full article

(This article belongs to the Section Forensics/Toxins)

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14 pages, 454 KiB

Open AccessArticle

Determination of Thermostability Degree of Lycopene in Watermelon (Citrullus lanatus)

by Bohuslava Tremlova, Hana Koudelkova Mikulaskova, Tomas Pencak, Karolina Tesikova, Simona Dordevic and Dani Dordevic

Separations 2021, 8(11), 220; https://doi.org/10.3390/separations8110220 - 17 Nov 2021

Cited by 1 | Viewed by 2737

Abstract

The aim of the work was to determine the degree of watermelon (Citrullus lanatus) thermostability according to the content of the present bioactive compounds and antioxidant properties. The watermelon samples were exposed to the following temperatures/time regimes: 40, 70, and 100 [...] Read more.

The aim of the work was to determine the degree of watermelon (Citrullus lanatus) thermostability according to the content of the present bioactive compounds and antioxidant properties. The watermelon samples were exposed to the following temperatures/time regimes: 40, 70, and 100 °C; 2, 5, and 15 min. The sample characteristics were monitored by spectrophotometric and chromatographic methods. Statistically significant (p < 0.05) differences were observed between the heat-treated samples compared to the heat-untreated control sample; differences were found almost between all samples. The total polyphenol content increased in all heat-treated samples. The highest total polyphenol content was observed among samples treated at 40 °C for 15 min (1.38 ± 0.01 mg/g). Lycopene content (measured by spectrophotometer) also increased in the same samples exposed to 40 °C for 5 min (65.45 ± 0.20 mg/kg), though higher temperatures (70 and 100 °C) resulted in lycopene degradation. Chromatographic method (measured by high-pressure liquid chromatography) showed lycopene degradation after each heating treatment. Not unambiguously, results and observations were not found in antioxidant activity due to oscillations in measured bioactive compounds. The obtained results emphasize processes in heat-treated watermelon, and they can be useful in the production of different products where this food commodity can be included. Full article

(This article belongs to the Section Analysis of Food and Beverages)

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6 pages, 618 KiB

Open AccessArticle

Liquid Chromatography-Tandem Mass Spectrometry for Detecting Myosin Light Chain 3 in Dry-Aged Beef

by Heeyoung Lee, Yoonji Heo, Jong-Chan Kim and You-Shin Shim

Separations 2021, 8(11), 219; https://doi.org/10.3390/separations8110219 - 16 Nov 2021

Viewed by 1833

Abstract

Liquid chromatography-tandem mass spectrometry (LC/MS/MS) is a more accurate technique for detecting proteins than electrophoresis-based methods such as western blotting. Because of its convenience, western blotting is commonly used for protein analysis in beef. We developed a method for detecting myosin light chain [...] Read more.

Liquid chromatography-tandem mass spectrometry (LC/MS/MS) is a more accurate technique for detecting proteins than electrophoresis-based methods such as western blotting. Because of its convenience, western blotting is commonly used for protein analysis in beef. We developed a method for detecting myosin light chain 3 (myl3) in beef samples, particularly dry-aged beef, using LC/MS/MS for quality testing. Musculus longissimus dorsi of Holstein was aged for 0, 2, 4, 5, 9, 11, 17, 20, and 24 weeks and used to measure the myl3 concentration. Because of the high molecular weight of myl3, the limitations of LC/MS/MS were overcome by implementing immunoprecipitation and digestion steps. Ultimately, a tryptic fragment of myl3 (13-mer), generated using immunoprecipitation and digestion by a biotinylated antibody, was detected using LC-MS/MS in positive ion mode through multiple reaction monitoring and analyte separation on a C18 column. Our method showed limits of detection and quantification of less than 0.3 and 0.8 μg/kg, respectively. However, differences in the myl3 concentrations according to the aging time were not significant (p > 0.05). After 12 weeks, myl3 disappeared in tested all samples, thus our analytical method can be used for accurate measurement of muscle protein in beef samples. Full article

(This article belongs to the Special Issue Extraction and Analysis of Compounds in Food Samples)

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12 pages, 2206 KiB

Open AccessFeature PaperArticle

Protective Effects of Dietary Supplement Spirulina (Spirulina platensis) against Toxically Impacts of Monosodium Glutamate in Blood and Behavior of Swiss mouse

by Adina Lia Longodor, Aurelia Coroian, Igori Balta, Marian Taulescu, Corina Toma, Bogdan Sevastre, Zamfir Marchiș, Luisa Andronie, Ioana Pop, Florica Matei, Octavia Maria Tamas-Krumpe and Stefania Maris

Separations 2021, 8(11), 218; https://doi.org/10.3390/separations8110218 - 15 Nov 2021

Cited by 7 | Viewed by 2945

Abstract

(1) Background: Well-known monosodium glutamate (E-621, MSG), originally used as a food flavor enhancer, was approved approximately in all countries, but the toxicity versus the safety of (MSG) are still unclear due to variable scientific toxicological reports. Moreover, it was reported to [...] Read more.

(1) Background: Well-known monosodium glutamate (E-621, MSG), originally used as a food flavor enhancer, was approved approximately in all countries, but the toxicity versus the safety of (MSG) are still unclear due to variable scientific toxicological reports. Moreover, it was reported to trigger elevated frequencies of nausea and headaches in humans and provide deleterious effects on laboratory animals. The objectives of the present study were to (i) estimate the possible toxic effects of the food additive MSG (ii) and the ameliorating protective effects of the dietary supplement spirulina (Spirulina platensis) on the biochemical parameters of blood and the damage produced in organs of Swiss mice after applying a supplementary daily dose of MSG for 4 weeks. (2) Methods: The present study was conducted on 20 mature Swiss mice, which were randomly organized into four groups of five Swiss mice. The treatments were (I) the control group, in which Swiss mice were fed only animal feed and drinking water; group II MSG1, which received 1 mL of MSG; group III MSG0.5, which was treated with 0.5 mL of MSG; and (IV) the group MSGS, which was treated with 1 mL of monosodium glutamate and 1 mL of spirulina (aiming to reduce the MSG toxicity). (3) Results: At the end of the experiment, Swiss mice treated with MSG demonstrated a passiveness regarding behavioral aspects. As we hypothesized, the parameters of the spirulina group reached similar values to the control group, and no histopathological observations have been found. Altogether, our findings evidenced that monosodium glutamate leads to histopathological changes in Swiss mice kidneys and caused important modifications for all biochemical parameters of the blood serum. Noticeably, the potential protective effect of Spirulina platensis was proved and was described by using the FTIR spectroscopy technique. (4) Conclusions: A diet rich in antioxidants and other plant-derived bioactive compounds may provide healthy nutrition, alleviating the potential side effects of some food additives. Full article

(This article belongs to the Special Issue Spectroscopic, Chromatographic, and Chemometric Techniques Applied in Food Products Characterization)

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13 pages, 837 KiB

Open AccessArticle

An Evaluation of the Equilibrium Properties in Hexane and Ethanol Extractive Systems for Moringa oleifera Seeds and Fatty Acid Profiles of the Extracts

by Karina Arguelles-Peña, José Arturo Olguín-Rojas, Andrés Antonio Acosta-Osorio, Ceferino Carrera, Gerardo F. Barbero, Miguel Ángel García-Alvarado and Guadalupe del Carmen Rodríguez-Jimenes

Separations 2021, 8(11), 217; https://doi.org/10.3390/separations8110217 - 12 Nov 2021

Cited by 7 | Viewed by 2759

Abstract

Until the present, oilseed extractions have been mainly performed using hexane: a toxic, non-sustainable solvent. Extraction methods using ethanol have recently been proposed and, to evaluate the suitability of ethanol as an alternative solvent, Moringa seeds with an oil content as high as [...] Read more.

Until the present, oilseed extractions have been mainly performed using hexane: a toxic, non-sustainable solvent. Extraction methods using ethanol have recently been proposed and, to evaluate the suitability of ethanol as an alternative solvent, Moringa seeds with an oil content as high as 40% have been chosen to determine the equilibrium properties in solid–liquid ethanol extractions. The equilibrium constant (K_eq) and the specific retained solution (M) of the extractive systems seeds–oil–hexane and seeds–oil–ethanol were determined and validated, following a counter-current multi-stage extraction model. The extractions were carried out at 40 and 50 °C, the mass to solvent ratios used were 1:5, 1:10 and 1:20, and shelled and unshelled seeds (kernels) were tested. The K_eq and M of the different kinetics revealed that K_eq was not infinite in the hexane systems, whereas the ethanol systems registered slightly lower values. Regarding M, although the seed powder allowed more rapid extractions, particle size was increased to reduce M for an easier phase preparation. Finally, a counter-current multi-stage extraction system was simulated and applied under suitable conditions. The fatty acid profiles for both types of extract were similar regarding their main components. definition: Full article

(This article belongs to the Special Issue Food Quality and Safety: Advances in Analytical Methods and Applications)

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17 pages, 2307 KiB

Open AccessArticle

Removal of Pyridine, Quinoline, and Aniline from Oil by Extraction with Aqueous Solution of (Hydroxy)quinolinium and Benzothiazolium Ionic Liquids in Various Ways

by Zhaojin Zhang, Yinan Li, Jing Gao, Alula Yohannes, Hang Song and Shun Yao

Separations 2021, 8(11), 216; https://doi.org/10.3390/separations8110216 - 12 Nov 2021

Cited by 3 | Viewed by 3215

Abstract

Based on above background, quinolinium, 8-hydroxy-quinolinium, and benzothiazolium ionic liquids, containing the acidic anions of methanesulfonate ([CH₃SO₃]⁻), phosphate ([H₂PO₄]⁻), p-toluenesulfonate ([p-TSA]⁻), and bisulfate ([HSO₄] [...] Read more.

Based on above background, quinolinium, 8-hydroxy-quinolinium, and benzothiazolium ionic liquids, containing the acidic anions of methanesulfonate ([CH₃SO₃]⁻), phosphate ([H₂PO₄]⁻), p-toluenesulfonate ([p-TSA]⁻), and bisulfate ([HSO₄]⁻) were synthesized. After comparison, the aqueous solution of benzothiazole bisulfate [HBth][HSO₄] was selected as the most ideal extractant for removing pyridine and aniline. Meanwhile, benzothiazole bisulfate [HBth][HSO₄] solution was found as the best one for removing quinoline from simulated oil. Then, the single stage extraction and two-step extraction were used in the extraction for the simulated oil containing pyridine, quinoline or aniline, and their mixture, respectively. Their denitrogenation performance on their N-removal effect was compared on the basis of structural features, and main extraction conditions were further investigated, including mass ratio of IL to water, mass ratio of IL to oil, and temperature. Furthermore, the extraction process was described by two kinetic equations. Recovery and reuse of IL were realized by back-extraction and liquid-liquid separation, and a related mechanism was speculated, according to all the experimental results. Finally, based on the developed method for preparing complex adsorbent tablets, corresponding immobilized IL was used to remove target objects, by solid phase extraction, in order to extend separation ways, which was more easily recovered after extraction. Full article

(This article belongs to the Special Issue Development and Application of Green or Sustainable Strategies in Analytical Chemistry)

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12 pages, 727 KiB

Open AccessArticle

Monitoring of Gold Biodistribution from Nanoparticles Using a HPLC-Visible Method

by Thomas Chaigneau, Arnaud Pallotta, Fatima Zahra Benaddi, Lucie Sancey, Said Chakir, Ariane Boudier and Igor Clarot

Separations 2021, 8(11), 215; https://doi.org/10.3390/separations8110215 - 12 Nov 2021

Cited by 2 | Viewed by 2231

Abstract

There is intensive research using gold nanoparticles for biomedical purposes, which have many advantages such as ease of synthesis and high reactivity. Their possible small size (<10 nm) can lead to the crossing of biological membranes and then to problematic dissemination and storage [...] Read more.

There is intensive research using gold nanoparticles for biomedical purposes, which have many advantages such as ease of synthesis and high reactivity. Their possible small size (<10 nm) can lead to the crossing of biological membranes and then to problematic dissemination and storage in organs that must be controlled and evaluated. In this work, a simple isocratic HPLC method was developed and validated to quantify the gold coming from nanoparticles in different biological samples. After a first carbonization step at 900 °C, the nanoparticles were oxidized by dibroma under acidic conditions, leading to tetrachloroaurate ions that could form ion pairs when adding rhodamine B. Finally, ion pairs were extracted and rhodamine B was evaluated to quantify the corresponding gold concentration by reversed-phase HPLC with visible detection. The method was validated for different organs (liver, spleen, lungs, kidneys, or brain) and fluids (plasma and urine) from rats and mice. Lastly, the developed method was used to evaluate the content of gold in organs and fluids after intravenous (IV) injection of nanoparticles. Full article

(This article belongs to the Special Issue Separations in Biomedical Analysis)

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11 pages, 1940 KiB

Open AccessArticle

Determination of Avermectins Residues in Soybean, Bean, and Maize Using a QuEChERS-Based Method and Ultra-High-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry

by Fernanda Uczay, Nelson M. G. Bandeira, Luana Floriano, Osmar D. Prestes, Martha B. Adaime and Renato Zanella

Separations 2021, 8(11), 214; https://doi.org/10.3390/separations8110214 - 11 Nov 2021

Cited by 3 | Viewed by 2310

Abstract

Soybean, maize, and bean are crops of great economic importance, but in recent years have suffered with infestations of the caterpillar Helicoverpa armigera, with the main reason being the resistance of this pest to most pesticides. Avermectin emamectin benzoate was recently released [...] Read more.

Soybean, maize, and bean are crops of great economic importance, but in recent years have suffered with infestations of the caterpillar Helicoverpa armigera, with the main reason being the resistance of this pest to most pesticides. Avermectin emamectin benzoate was recently released to control this pest. Other avermectins, like abamectin, doramectin, eprinomectin, and ivermectin are used in large scale because they potent acaricidal, anthelmintic, and insecticidal activities. Thus, a simple and fast method for the determination of avermectins in these crops based on a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction procedure and ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) analysis was developed and validated. For extraction, water followed by acetonitrile:isopropanol and a partition step with salts was stablished. With the clean-up step using activated EMR-Lipid, limits of detection of 1.2 μg kg⁻¹ for abamectin, doramectin, emamectin benzoate, and ivermectin, and of 2.4 μg kg⁻¹ for eprinomectin were achieved. The validation showed satisfactory results and the method was successfully applied to commercial samples, indicating that it is suitable for routine analysis. Full article

(This article belongs to the Special Issue Advances in the Separation Analysis of Food Constituents, Residues, and Contaminants)

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14 pages, 1254 KiB

Open AccessFeature PaperArticle

Determination of Sr–Nd–Pb Isotopic Ratios of Rock Reference Materials Using Column Separation Techniques and TIMS

by Hui Je Jo, Hyo Min Lee, Go-Eun Kim, Won Myung Choi and Taehoon Kim

Separations 2021, 8(11), 213; https://doi.org/10.3390/separations8110213 - 10 Nov 2021

Cited by 10 | Viewed by 2828

Abstract

Thermal ionization mass spectrometry (TIMS) can provide highly accurate strontium (Sr), neodymium (Nd), and lead (Pb) isotope measurements for geological and environmental samples. Traces of these isotopes are useful for understanding crustal reworking and growth. In this study, we conducted a sequential separation [...] Read more.

Thermal ionization mass spectrometry (TIMS) can provide highly accurate strontium (Sr), neodymium (Nd), and lead (Pb) isotope measurements for geological and environmental samples. Traces of these isotopes are useful for understanding crustal reworking and growth. In this study, we conducted a sequential separation of Sr, Nd, and Pb and subsequently measured the ⁸⁷Sr/⁸⁶Sr, ¹⁴³Nd/¹⁴⁴Nd, ²⁰⁶Pb/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁴Pb, and ²⁰⁸Pb/²⁰⁴Pb ratios of 13 widely used rock certified reference materials (CRMs), namely BCR-2, BHVO-2, GSP-2, JG-1a, HISS-1, JLk-1, JSd-1, JSd-2, JSd-3, LKSD-1, MAG-1, SGR-1, and 4353A, using TIMS. In particular, we reported the first isotopic ratios of Sr, Nd, and Pb in 4353A, Sr and Nd in HISS-1 and SGR-1, and Sr in JLk-1, JSd-2, JSd-3, and LKSD-1. The Sr–Nd–Pb isotopic compositions of most in-house CRMs were indistinguishable from previously reported values, although the Sr and Pb isotopic ratios of GSP-2, JSd-2, JSd-3, and LKSD-1 obtained in different aliquots and/or batches varied slightly. Hence, these rock reference materials can be used for monitoring the sample accuracy and assessing the quality of Sr–Nd–Pb isotope analyses. Full article

(This article belongs to the Special Issue Application of Mass Spectrometry Technology in Geochemistry)

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15 pages, 18290 KiB

Open AccessArticle

Aqueous Two-Phase System–Ion Chromatography for Determination of Thiocyanate in Raw Milk

by Bin Jiang, Shaojing Zhong, Hongliang Yu, Peifeng Chen, Baoyun Li, Dongmei Li, Chunhong Liu, Zhibiao Feng and Bo Tian

Separations 2021, 8(11), 212; https://doi.org/10.3390/separations8110212 - 9 Nov 2021

Cited by 3 | Viewed by 2015

Abstract

Thiocyanate could effectively inhibit bacteria in milk and extend the shelf life of milk. However, excessive addition will lead to health risks. Therefore, the determination of thiocyanate in raw milk has received a lot of attention, but the determination could be interfered with [...] Read more.

Thiocyanate could effectively inhibit bacteria in milk and extend the shelf life of milk. However, excessive addition will lead to health risks. Therefore, the determination of thiocyanate in raw milk has received a lot of attention, but the determination could be interfered with by other components in raw milk and the pre-treatment of raw milk is complex. In this study, a new pretreatment method combined with ion chromatography (IC) for rapid and sensitive determination of thiocyanate is proposed. An acetonitrile/(NH₄)₂SO₄ aqueous two-phase system (ATPS) was developed for the separation and enrichment of thiocyanate in raw milk. Response surface methodology was performed to optimize the extraction conditions and an efficient pretreatment were obtained using ATPS composed of 42% acetonitrile (w/w) and 16% (NH₄)₂SO₄ (w/w), with the pH 4.7, and the recovery of thiocyanate reached 107.24 ± 0.5%, and the enrichment ratio was 10.74 ± 0.03. IC was used to establish a thiocyanate enrichment method. The linear range was from 0.05 to 15 mg/L and R² = 0.998, the limit of detection (LOD) was 0.2 μg/L, the limit of quantification (LQD) was 0.6 μg/L. Hence, it is feasible to combine ATPS with IC for the enrichment and determination of thiocyanate in raw milk. Full article

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17 pages, 6260 KiB

Open AccessArticle

Comparative Extraction of Aluminum Group Metals Using Acetic Acid Derivatives with Three Different-Sized Frameworks for Coordination

by Keisuke Ohto, Nako Fuchiwaki, Hiroaki Furugou, Shintaro Morisada, Hidetaka Kawakita, Marco Wenzel and Jan J. Weigand

Separations 2021, 8(11), 211; https://doi.org/10.3390/separations8110211 - 8 Nov 2021

Cited by 5 | Viewed by 1976

Abstract

We prepared acetic acid derivatives using three different frameworks, calix[4]arene, alkenyltrimethylol, and trihydroxytriphenylmethane, which differ in the number and size of their coordination sites. We further investigated the extraction properties for aluminum group metal ions. All three extraction reagents exhibited increased extraction compared [...] Read more.

We prepared acetic acid derivatives using three different frameworks, calix[4]arene, alkenyltrimethylol, and trihydroxytriphenylmethane, which differ in the number and size of their coordination sites. We further investigated the extraction properties for aluminum group metal ions. All three extraction reagents exhibited increased extraction compared with the corresponding monomeric compounds, owing to structural effects. The extraction reaction and extraction equilibrium constants were determined using a slope analysis. Their extraction abilities, separation efficiencies, and potential coordination modes are discussed using the extraction equilibrium constants, half-pH values, and spectroscopic data. The calix[4]arene and trihydroxytriphenylmethane derivatives demonstrated allosteric co-extraction of indium ions (In³⁺) with an unexpected stoichiometry of 1:2. Full article

(This article belongs to the Section Analysis of Energies)

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13 pages, 3169 KiB

Open AccessArticle

Optimization of the Outlet Flow Ratio of Mini-Hydrocyclone Separators Using the Full Factorial Design Method to Determine the Separation Efficiency

by Hyung-Wook Yi, Je-Young Kwon, Yu-Wool Lee and Myung-Chang Kang

Separations 2021, 8(11), 210; https://doi.org/10.3390/separations8110210 - 7 Nov 2021

Cited by 5 | Viewed by 4173

Abstract

Cyclone separators are widely used to eliminate particles flowing through pipelines in equipment from various industrial processes. Unlike general filters, cyclone separators can constantly and effectively eliminate foreign substances present in the fluid flowing through the equipment. In this study, we fabricated mini-hydrocyclone [...] Read more.

Cyclone separators are widely used to eliminate particles flowing through pipelines in equipment from various industrial processes. Unlike general filters, cyclone separators can constantly and effectively eliminate foreign substances present in the fluid flowing through the equipment. In this study, we fabricated mini-hydrocyclone separators using the 3D printing method for application in the steam and water analysis system (SWAS) in a thermal power plant instead of the conventional strainer filter. The gravimetric method was used to measure the separation efficiency of the hydrocyclone separators and compare the weights of the sludge discharged from the underflow and overflow outlets. The outlet flow ratio was optimized by adjusting the diameters of the spigot and vortex finder of the separators, which influenced the outlet flow rate. To apply the gravimetric method more objectively, the optimum values of the diameters of the vortex finder and spigot with an outlet flow ratio of 1 were determined using full factorial design (FFD) in the design of experiments (DOE). The obtained values were verified through numerical analysis using the ANSYS Fluent software. Furthermore, after fabrication of the mini-hydrocyclone separators using an SLA-type 3D printer, we conducted a numerical analysis, and the results were compared with that of the actual experiment. It was observed that the use of FFD can effectively optimize the desired outlet flow ratio in the mini-hydrocyclone separator. In addition, the changes in the outlet flow ratio do not affect the separation efficiency of the cyclone separators. Full article

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16 pages, 2257 KiB

Open AccessArticle

Validated Modernized Assay for Foscarnet in Pharmaceutical Formulations Using Suppressed Ion Chromatography Developed through a Quality by Design Approach

by Ngoc Phuoc Dinh, Adel Shamshir, Gjani Hulaj and Tobias Jonsson

Separations 2021, 8(11), 209; https://doi.org/10.3390/separations8110209 - 5 Nov 2021

Cited by 3 | Viewed by 3427

Abstract

Inspired by the United States Pharmacopoeia (USP) “monograph modernization” initiative, we developed and validated an assay for foscarnet sodium injection solution (“foscavir”), following quality by design (QbD) principles, incorporating design of experiments (DoE) and multivariate data analysis to establish the design space and [...] Read more.

Inspired by the United States Pharmacopoeia (USP) “monograph modernization” initiative, we developed and validated an assay for foscarnet sodium injection solution (“foscavir”), following quality by design (QbD) principles, incorporating design of experiments (DoE) and multivariate data analysis to establish the design space and robust setpoint of the method. The resulting analytical procedure was based on ion chromatography (IC) with suppressed conductivity detection, employing an isocratic carbonate–bicarbonate eluent system. The assay was successfully validated at the robust setpoint conditions, according to the guidelines established by the International Council for Harmonization (ICH). The linear range stretched at least from 5 to 100 mg/L with high repeatability (relative standard deviation, RSD ≤ 0.3%) both at the target concentration (60 mg/L) and at 50% and 150% from this level. Special attention was given to establish a rugged assay that would be easily transferable between laboratories, and the recorded recoveries of 98.2–100.5% for both the formulated drug product and the drug substance during intermediate precision evaluation at different analysis situations indicated that this mission was accomplished. A multivariate assessment of intermediate precision data acquired using an experimental design scheme revealed that the assay was not adversely affected by any of the situation variables, including the use of different liquid chromatography instrument types, regardless of if they were constructed from inert materials or stainless steel that had been passivated, even though such problems have been reported in several previous methods for analysis of foscarnet. Full article

(This article belongs to the Special Issue Innovation of Analysis Methods in Pharmaceutical Chemistry)

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10 pages, 14059 KiB

Open AccessArticle

Isolation and Identification of Non-Conjugated Linoleic Acid from Processed Panax ginseng Using LC-MS/MS and ¹H-NMR

by Tae-Kyung Kim, Changsuk Lee, Taek-Hee Nam, Yong-Ki Seo, Kyeong-Soo Kim, Kimoon Kang, Seok-Hun Yun, Seok-Hwan Yoon and Jaeho Jeong

Separations 2021, 8(11), 208; https://doi.org/10.3390/separations8110208 - 4 Nov 2021

Cited by 1 | Viewed by 2711

Abstract

Black ginseng exhibits numerous pharmacological activities due to higher and more diverse ginsenosides than unprocessed white ginseng. The ginsenoside derivatives have been investigated in order to determine their chemical structures and pharmacological activities. We found a peak which was increased 10-fold but unidentified [...] Read more.

Black ginseng exhibits numerous pharmacological activities due to higher and more diverse ginsenosides than unprocessed white ginseng. The ginsenoside derivatives have been investigated in order to determine their chemical structures and pharmacological activities. We found a peak which was increased 10-fold but unidentified in the methanol extracts of a black ginseng product. The unknown peak was tracked and identified as linoleic acid rather than a ginsenoside derivative using liquid chromatography–tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR) spectroscopy. NMR analysis confirmed no presence of conjugated linoleic acids. Ginsenoside profiles and linoleic acid contents in black ginseng products were quantified using LC-MS/MS. Linoleic acid content was more directly proportional to the number of applied thermal cycles in the manufacturing process than any ginsenosides. Full article

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15 pages, 1174 KiB

Open AccessReview

Anticancer and Anti-Inflammatory Effects of Tomentosin: Cellular and Molecular Mechanisms

by Nasreddine El Omari, Naoual El Menyiy, Gokhan Zengin, Bey Hing Goh, Monica Gallo, Domenico Montesano, Daniele Naviglio and Abdelhakim Bouyahya

Separations 2021, 8(11), 207; https://doi.org/10.3390/separations8110207 - 4 Nov 2021

Cited by 17 | Viewed by 3240

Abstract

Tomentosin is a natural compound known for its presence in some medicinal plants of the Asteraceae family such as Inula viscosa. Recent studies have highlighted its anticancer and anti-inflammatory properties. Its anticancer mechanisms are unique and act at different levels ranging from [...] Read more.

Tomentosin is a natural compound known for its presence in some medicinal plants of the Asteraceae family such as Inula viscosa. Recent studies have highlighted its anticancer and anti-inflammatory properties. Its anticancer mechanisms are unique and act at different levels ranging from cellular organization to molecular transcriptional factors and epigenetic modifications. Tomentosin’s possession of the modulatory effect on telomerase expression on tumor cell lines has captured the interest of researchers and spurred a more robust study on its anticancer effect. Since inflammation has a close link with cancer disease, this natural compound appears to be a potential cancer-fighting drug. Indeed, its recently demonstrated anti-inflammatory action can be considered as a starting point for its evaluation as an anticancer chemo-preventive agent Full article

(This article belongs to the Special Issue Early Career Stars in Bioanalysis/Clinical Analysis)

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17 pages, 544 KiB

Open AccessEditor’s ChoiceReview

A Review on the Nanofiltration Process for Treating Wastewaters from the Petroleum Industry

by Shahryar Jafarinejad and Milad Rabbani Esfahani

Separations 2021, 8(11), 206; https://doi.org/10.3390/separations8110206 - 4 Nov 2021

Cited by 29 | Viewed by 4556

Abstract

Activities and/or processes in different segments of the petroleum industry, including upstream and downstream, generate aqueous waste streams containing oil and various contaminants that require treatment/purification before release/reuse. Nanofiltration (NF) technology has been approved as an efficient technology for treating wastewater streams from [...] Read more.

Activities and/or processes in different segments of the petroleum industry, including upstream and downstream, generate aqueous waste streams containing oil and various contaminants that require treatment/purification before release/reuse. Nanofiltration (NF) technology has been approved as an efficient technology for treating wastewater streams from the petroleum industry. The primary critical issues in an NF treatment process can be listed as mitigation of membrane fouling; selection of appropriate pre-treatment process; and selection of a suitable, cost-effective, non-hazardous cleaning strategy. In this study, NF separation mechanisms, membrane fabrication/modification, effective factors on NF performance, and fouling are briefly reviewed. Then, a summary of recent NF treatment studies on various petroleum wastewaters and performance evaluation is presented. Finally, based on the gaps identified in the field, the conclusions and future perspectives are discussed. Full article

(This article belongs to the Section Environmental Separations)

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13 pages, 17994 KiB

Open AccessArticle

Identification of Block-Structured Covariance Matrix on an Example of Metabolomic Data

by Adam Mieldzioc, Monika Mokrzycka and Aneta Sawikowska

Separations 2021, 8(11), 205; https://doi.org/10.3390/separations8110205 - 4 Nov 2021

Cited by 4 | Viewed by 2512

Abstract

Modern investigation techniques (e.g., metabolomic, proteomic, lipidomic, genomic, transcriptomic, phenotypic), allow to collect high-dimensional data, where the number of observations is smaller than the number of features. In such cases, for statistical analyzing, standard methods cannot be applied or lead to ill-conditioned estimators [...] Read more.

Modern investigation techniques (e.g., metabolomic, proteomic, lipidomic, genomic, transcriptomic, phenotypic), allow to collect high-dimensional data, where the number of observations is smaller than the number of features. In such cases, for statistical analyzing, standard methods cannot be applied or lead to ill-conditioned estimators of the covariance matrix. To analyze the data, we need an estimator of the covariance matrix with good properties (e.g., positive definiteness), and therefore covariance matrix identification is crucial. The paper presents an approach to determine the block-structured estimator of the covariance matrix based on an example of metabolomic data on the drought resistance of barley. This method can be used in many fields of science, e.g., in agriculture, medicine, food and nutritional sciences, toxicology, functional genomics and nutrigenomics. Full article

(This article belongs to the Special Issue Chemometrics in Metabolomics and Proteomics)

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14 pages, 2316 KiB

Open AccessArticle

Alternative Method for HDL and Exosome Isolation with Small Serum Volumes and Their Characterizations

by Rian Ka Praja, Wisitsak Phoksawat, Patcharaporn Tippayawat, Amonrat Jumnainsong and Chanvit Leelayuwat

Separations 2021, 8(11), 204; https://doi.org/10.3390/separations8110204 - 3 Nov 2021

Cited by 4 | Viewed by 2870

Abstract

High-density lipoprotein (HDL) and exosomes are promising sources of biomarkers. However, the limited sample volume and access to the ultracentrifuge equipment are still an issue during HDL and exosome isolation. This study aimed to isolate HDL and exosomes using an ultracentrifugation-free method with [...] Read more.

High-density lipoprotein (HDL) and exosomes are promising sources of biomarkers. However, the limited sample volume and access to the ultracentrifuge equipment are still an issue during HDL and exosome isolation. This study aimed to isolate HDL and exosomes using an ultracentrifugation-free method with various small serum volumes. HDL was isolated from 200 µL (HDL200) and 500 µL (HDL500) of sera. Three different volumes: 50 µL (Exo50), 100 µL (Exo100), and 250 µL (Exo250) were used for exosome isolation. HDL and exosomes were isolated using commercial kits with the modified method and characterized by multiple approaches. The HDL levels of HDL200 and HDL500 were not significantly different (p > 0.05), with percent recoveries of >90%. HDL200 and HDL500 had the same protein pattern with a biochemical similarity of 99.60 ± 0.10%. The particle sizes of Exo50, Exo100, and Exo250 were in the expected range. All isolated exosomes exhibited a similar protein pattern with a biochemical similarity of >99%. In conclusion, two different serum volumes (200 and 500 µL) and three different serum volumes (50, 100, and 250 µL) can be employed for HDL and exosome isolation, respectively. The possibility of HDL and exosome isolation with small volumes will accelerate biomarker discoveries with various molecular diagnostic approaches. Full article

(This article belongs to the Special Issue Fractionation and Sample Preparation Techniques Used in Bioanalyses)

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9 pages, 1130 KiB

Open AccessCommunication

Phytochemical Constituents Identified from the Aerial Parts of Lespedeza cuneata and Their Effects on Lipid Metabolism during Adipocyte Maturation

by Heesun Kang, Min Jeong Yoo, Sang Ah Yi, Tae Wan Kim, Ji Won Ha, Myung Woo Na, Kun Hee Park, Seon-Hee Kim, Jeung-Whan Han, Tae Su Jang and Ki Hyun Kim

Separations 2021, 8(11), 203; https://doi.org/10.3390/separations8110203 - 3 Nov 2021

Cited by 2 | Viewed by 2133

Abstract

Lespedeza cuneata, belonging to Fabaceae, is well-known as Chinese bushclover, and it has been used in traditional folk medicines for the treatment of disorders, such as diabetes, hematuria, and insomnia. As part of continuing research projects to discover interesting natural compounds with [...] Read more.

Lespedeza cuneata, belonging to Fabaceae, is well-known as Chinese bushclover, and it has been used in traditional folk medicines for the treatment of disorders, such as diabetes, hematuria, and insomnia. As part of continuing research projects to discover interesting natural compounds with biological activities from Korean medicinal plants, the phytochemical investigation of L. cuneata resulted in the isolation of five chemical constituents: α-tocopherol (1), 7a-methoxy-α-tocopherol (2), 13(R)-hydroxy-octadeca-(9Z,11E,15Z)-trien-oic acid (3), α-dimorphecolic acid (4), and lupeol (5). The structural determination of the isolated compounds was elucidated from data gathered through nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography–mass spectrometry (LC/MS). Until now, this study is the first to report these five compounds from the plant L. cuneata. Moreover, these isolated compounds (1–5) were evaluated for their anti-adipogenesis effects and their role in lipid metabolism during adipocyte maturation. As a result, the upregulation of mRNA expression levels of Fabp4 from 3T3-L1 pre-adipocytes treated with compounds 3 and 4 demonstrated that these compounds efficiently induced adipocyte differentiation. Furthermore, compounds 3 and 4 were found to regulate lipid metabolism by the induction of lipolytic and of lipogenic gene expressions. Therefore, experimental data from these findings supported that the compounds 3 and 4 induce the adipogenesis of 3T3-L1 pre-adipocytes and regulate lipid metabolism. Full article

(This article belongs to the Special Issue Chromatographic Analysis of Biological Samples)

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9 pages, 2206 KiB

Open AccessArticle

Adsorption of Metallic Ions on Amidoxime-Chitosan/Cellulose Hydrogels

by Takaaki Tatsumi, Yoshiro Tahara and Michiaki Matsumoto

Separations 2021, 8(11), 202; https://doi.org/10.3390/separations8110202 - 3 Nov 2021

Cited by 9 | Viewed by 2137

Abstract

Adsorption using natural compounds is an attractive separation technique for recovering heavy metals from aqueous media. Although chitosan, which is a natural polysaccharide, is an environmentally benign adsorbent, it dissolves in an acidic aqueous medium. In this study, we prepared adsorbents consisting of [...] Read more.

Adsorption using natural compounds is an attractive separation technique for recovering heavy metals from aqueous media. Although chitosan, which is a natural polysaccharide, is an environmentally benign adsorbent, it dissolves in an acidic aqueous medium. In this study, we prepared adsorbents consisting of chitosan modified with amidoxime groups for improving metal adsorptivity, and cellulose for improving gel stability using an ionic liquid, and examined their adsorption characteristics for metal ions. The prepared amidoxime-chitosan/cellulose hydrogels had a mechanical strength without cross-linking. All the investigated metals were adsorbed on the amidoxime-chitosan/cellulose hydrogels in the following adsorptivity order: Cu ≈ Ag > Ni > Zn. The adsorptivity of the metal ions increased with pH due to a proton exchange reaction. From the Langmuir adsorption isotherm, the Langmuir constant for Cu exceeded those of other metals because amidoxime has higher Cu affinity. The pseudo-second-order reaction model best described the adsorption kinetics with metal chelate formation being the rate-determining step. Because amidoxime-chitosan/cellulose hydrogels had higher physical stability and higher Cu selectivity, they were found to be a promising, environmentally benign adsorbent. Full article

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15 pages, 999 KiB

Open AccessArticle

Arginine, as a Key Indicator for Real-Time Stability Monitoring of Quality Control in the Newborn Screening Test Using Dried Blood Spot

by Hyun-Seung Lee

Separations 2021, 8(11), 201; https://doi.org/10.3390/separations8110201 - 2 Nov 2021

Cited by 1 | Viewed by 2194

Abstract

Dried blood spots (DBS) have advantages such as minimizing blood collection volume and the distress to neonate. DBS have been used for tandem mass spectrometry (MS/MS)-based newborn screening tests (NST) of amino acid (AA) and acylcarnitine. The Newborn Screening Quality Assurance Program (NSQAP) [...] Read more.

Dried blood spots (DBS) have advantages such as minimizing blood collection volume and the distress to neonate. DBS have been used for tandem mass spectrometry (MS/MS)-based newborn screening tests (NST) of amino acid (AA) and acylcarnitine. The Newborn Screening Quality Assurance Program (NSQAP) have been provided quality control (QC) materials for MS/MS, as DBS cards. The NSQAP is generally provided within 14 months of the shelf life and the recommended storage condition is at −10 °C to −30 °C. Previously, several accelerated degradation studies had been performed to determine the transportation stability and short-term stability of AAs and acylcarnitines in DBS. However, the experimental condition is markedly different to the storage condition. We performed long-term monitoring for the real-time stability of seven AAs and 14 acylcarnitines from three levels of 2012 NSQAP QC materials across a time period of 788 days. Arginine suddenly yielded a catastrophic degeneration pattern, which started around D300. When comparing this with previous accelerated degradation studies, methionine, tyrosine, citrulline, and acetylcarnitine did not show a remarkable measurand drift for the real-time stability, except for arginine. Our study showed that arginine would require intensive QC monitoring in routine practice, and should be used for the assessment of the stability in long-term storage of DBS samples for biobanking. Full article

(This article belongs to the Section Bioanalysis/Clinical Analysis)

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11 pages, 2781 KiB

Open AccessArticle

The Preparation of High Purity of Rebaudioside A and Stevioside and the Enrichment of Rebaudioside C by Subsequent Twice Crystallizations from Natural Stevia Resources

by Yingjie Luo, Lincai Peng, Zhaoziyuan Yang, Shun Yao and Hang Song

Separations 2021, 8(11), 200; https://doi.org/10.3390/separations8110200 - 2 Nov 2021

Cited by 2 | Viewed by 2222

Abstract

A comprehensive utilization of rebaudioside A (RA), stevioside (ST), and rebaudioside C (RC) from natural stevia resources was proposed. The influence of the solvent, solvent concentration, solid-liquid ratio, temperature, and time on the purity and recovery were investigated with response surface methodology. A [...] Read more.

A comprehensive utilization of rebaudioside A (RA), stevioside (ST), and rebaudioside C (RC) from natural stevia resources was proposed. The influence of the solvent, solvent concentration, solid-liquid ratio, temperature, and time on the purity and recovery were investigated with response surface methodology. A 99% purity and 81% recovery of the RA were achieved by one crystallization of crude stevia under optimized conditions. Around a 95% purity and 80% recovery of the ST were easily achieved by the recrystallization of less value of mother liquor sugar (MLS) with a certain concentration of isopropyl alcohol–methanol aqueous solution. During the crystallization of the ST, the enriched RC in the liquid phase was more than three times higher than that in the crude stevia, which can provide cheaper RC raw material for the subsequent preparation of very expensive and high-purity RC. Full article

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15 pages, 1918 KiB

Open AccessReview

Research Progress on Quality Control Methods for Xiaochaihu Preparations

by Guangzheng Xu, Hui Wang, Yingqian Deng, Keyi Xie, Weibo Zhao and Xingchu Gong

Separations 2021, 8(11), 199; https://doi.org/10.3390/separations8110199 - 1 Nov 2021

Cited by 4 | Viewed by 2195

Abstract

Xiaochaihu (XCH) is a classic Chinese medicine formula. XCH tablet, XCH granule, XCH capsule, and XCH effervescent tablet are included in the Chinese Pharmacopoeia. In this review, the formula and quality standards of XCH preparations at home and abroad were compared. The differences [...] Read more.

Xiaochaihu (XCH) is a classic Chinese medicine formula. XCH tablet, XCH granule, XCH capsule, and XCH effervescent tablet are included in the Chinese Pharmacopoeia. In this review, the formula and quality standards of XCH preparations at home and abroad were compared. The differences in manufacturing process of XCH preparations are discussed. The progress of research on the qualitative identification, quantitative detection and fingerprint chromatogram/specific chromatogram of XCH preparations was reviewed. The characteristic components of Pinelliae Rhizoma Praeparatum Cum Zingibere Et Alumine and Jujubae Fructus was rarely analyzed for XCH preparations. It is suggested that the specificity of drug quality detection methods should be improved. Considering drug safety and drug efficacy, it is suggested to set the upper and lower limits of the content of saikosaponins. The standards for heavy metals and other limited items for XCH preparations are also suggested to be set. Full article

(This article belongs to the Special Issue Separation, Extraction and Purification of Natural Products from Plants)

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11 pages, 1200 KiB

Open AccessArticle

Quality Distinguish of Red Ginseng from Different Origins by HPLC–ELSD/PDA Combined with HPSEC–MALLS–RID, Focus on the Sugar-Markers

by Qian Cheng, Shuhuan Peng, Fangyi Li, Pengdi Cui, Chunxia Zhao, Xiaohui Yan, Tongchuan Suo, Chunhua Wang, Yongzhi He and Zheng Li

Separations 2021, 8(11), 198; https://doi.org/10.3390/separations8110198 - 27 Oct 2021

Cited by 4 | Viewed by 2915

Abstract

Red ginseng (RG) has been extensively utilized in Asian countries due to its pharmacological effects. For the quality evaluation of RG, small molecules, such as ginsenosides, have been widely considered as candidates of its quality markers (Q-markers), and various analytical techniques have been [...] Read more.

Red ginseng (RG) has been extensively utilized in Asian countries due to its pharmacological effects. For the quality evaluation of RG, small molecules, such as ginsenosides, have been widely considered as candidates of its quality markers (Q-markers), and various analytical techniques have been developed in order to identify these compounds. However, despite the efforts to analyze the hydrophobic constituents, it is worth pointing out that about 60% of the mass of RG is made of carbohydrates, including mono-, oligo- and polysaccharides. Consequently, the quality differentiation and identification of RG from the perspective of sugar-markers should be focused. High performance liquid chromatography and evaporative light scattering detector (HPLC–ELSD) method for the determination of disaccharides in RG was established. Furthermore, high performance size exclusion chromatography–multi-angle laser light scattering–refractive index detector (HPSEC–MALLS–RID) for the determination of molecular weight and high performance liquid chromatography photodiode array (HPLC–PDA) for the determination of compositional monosaccharides in RG polysaccharides were also established. HPLC–ELSD/PDA combined with HPSEC–MALLS–RID could be used to determine the contents of disaccharides, molecular weights, and compositional monosaccharides of RG polysaccharides, which could be used for quality control, and this is a new view on the sugar marker to quality differentiation of various origins of RG. Full article

(This article belongs to the Special Issue Separation, Extraction and Purification of Natural Products from Plants)

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10 pages, 1073 KiB

Open AccessArticle

Determination of Fosetyl-Aluminum in Wheat Flour with Extract-Dilute-Shoot Procedure and Hydrophilic Interaction Liquid Chromatography Tandem Mass Spectrometry

by Xianjiang Li, Sheng Wang, Zhen Guo, Xiuqin Li, Qinghe Zhang and Hongmei Li

Separations 2021, 8(11), 197; https://doi.org/10.3390/separations8110197 - 24 Oct 2021

Cited by 9 | Viewed by 2899

Abstract

Fosetyl-aluminum is a widely used ionic fungicide. This pesticide is not amenable to the common multi-residue sample preparation methods. Herein, this paper describes a novel method for the simple and sensitive determination of fosetyl-aluminum residue in wheat flour. The sample preparation method involved [...] Read more.

Fosetyl-aluminum is a widely used ionic fungicide. This pesticide is not amenable to the common multi-residue sample preparation methods. Herein, this paper describes a novel method for the simple and sensitive determination of fosetyl-aluminum residue in wheat flour. The sample preparation method involved extraction with water under ultrasonication and subsequent dilution with six-fold acetonitrile. The fosetyl-aluminum concentration was determined by hydrophilic interaction liquid chromatography tandem mass spectrometry. The limit of detection and quantification were only 5 and 10 ng/g, respectively, which meet the requirement of the current European legislation. Matrix-matched linearity (r² = 0.9999) was established in the range of 10–2000 ng/g. Satisfactory recoveries were achieved in the range of 95.6% to 105.2% for three levels of spiked samples (10, 50, and 100 ng/g). Finally, the method was applied to analyzing 75 wheat flour samples produced in four provinces in China. Two samples were positive with concentrations over the limit of detection. This is the first method focusing on fosetyl-aluminum determination in wheat flour with an extract-dilute-shoot strategy and is very promising for the routine quality control of fosetyl-aluminum in similar cereal matrices. Full article

(This article belongs to the Special Issue Advances of Accurate Quantification Methods in Food Analysis)

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Separations, Volume 8, Issue 11 (November 2021) – 32 articles

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