Separations

19 pages, 5660 KiB

Open AccessArticle

Chromatographic Profiling with Machine Learning Discriminates the Maturity Grades of Nicotiana tabacum L. Leaves

by Yi Chen, Miao Tian, Gaokun Zhao, Hongmei Lu, Zhimin Zhang and Congming Zou

Separations 2021, 8(1), 9; https://doi.org/10.3390/separations8010009 - 19 Jan 2021

Cited by 3 | Viewed by 3057

Nicotiana tabacum L. (NTL) is an important agricultural and economical crop. Its maturity is one of the key factors affecting its quality. Traditionally, maturity is discriminated visually by humans, which is subjective and empirical. In this study, we concentrated on detecting as many [...] Read more.

Nicotiana tabacum L. (NTL) is an important agricultural and economical crop. Its maturity is one of the key factors affecting its quality. Traditionally, maturity is discriminated visually by humans, which is subjective and empirical. In this study, we concentrated on detecting as many compounds as possible in NTL leaves from different maturity grades using ultra-performance liquid chromatography ion trap time-of-flight mass spectrometry (UPLC-IT-TOF/MS). Then, the low-dimensional embedding of LC-MS dataset by t-distributed stochastic neighbor embedding (t-SNE) clearly showed the separation of the leaves from different maturity grades. The discriminant models between different maturity grades were established using orthogonal partial least squares discriminant analysis (OPLS-DA). The quality metrics of the models are R²Y = 0.939 and Q² = 0.742 (unripe and ripe), R²Y = 0.900 and Q² = 0.847 (overripe and ripe), and R²Y = 0.972 and Q² = 0.930 (overripe and unripe). The differential metabolites were screened by their variable importance in projection (VIP) and p-Values. The existing tandem mass spectrometry library of plant metabolites, the user-defined library of structures, and MS-FINDER were combined to identify these metabolites. A total of 49 compounds were identified, including 12 amines, 14 lipids, 10 phenols, and 13 others. The results can be used to discriminate the maturity grades of the leaves and ensure their quality. Full article

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

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9 pages, 5415 KiB

Open AccessArticle

Antitumor Potential of Green Synthesized ZnONPs Using Root Extract of Withania somnifera against Human Breast Cancer Cell Line

by Kollur Shiva Prasad, Shashanka K Prasad, Ravindra Veerapur, Ghada Lamraoui, Ashwini Prasad, M. N. Nagendra Prasad, Sandeep Kumar Singh, Najat Marraiki, Asad Syed and Chandan Shivamallu

Separations 2021, 8(1), 8; https://doi.org/10.3390/separations8010008 - 18 Jan 2021

Cited by 21 | Viewed by 4525

Abstract

Herein we report the synthesis of zinc oxide nanoparticles (ZnONPs) using Withania somnifera root extract (WSE) as an effective chelating agent. The microscopic techniques viz., X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and [...] Read more.

Herein we report the synthesis of zinc oxide nanoparticles (ZnONPs) using Withania somnifera root extract (WSE) as an effective chelating agent. The microscopic techniques viz., X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED) were employed to analyze the as-obtained ZnONPs. The crystalline planes observed from the XRD pattern agrees with the hexagonal wurtzite structure of the as-prepared ZnONPs. The aggregations and agglomerations observed in the SEM images indicated that the size of the as-prepared ZnONPs was between 30 and 43 nm. The interplanar distance between the lattice fringes observed in the HRTEM image was found to be 0.253 nm, which is in good agreement with the (100) plane obtained in the XRD pattern. Furthermore, the anti-breast cancer cytotoxic evaluation was carried out using the MCF-7 cell line, and the results showed significant cytotoxic effects in a dose-dependent manner. Full article

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13 pages, 2151 KiB

Open AccessArticle

Dissolution Testing of Nicotine Release from OTDN Pouches: Product Characterization and Product-to-Product Comparison

by Fadi Aldeek, Nicholas McCutcheon, Cameron Smith, John H. Miller and Timothy L. Danielson

Separations 2021, 8(1), 7; https://doi.org/10.3390/separations8010007 - 7 Jan 2021

Cited by 18 | Viewed by 8884

Abstract

In recent years, oral tobacco-derived nicotine (OTDN) pouches have emerged as a new oral tobacco product category. They are available in a variety of flavors and do not contain cut or ground tobacco leaf. The on!^® nicotine pouches fall within this category [...] Read more.

In recent years, oral tobacco-derived nicotine (OTDN) pouches have emerged as a new oral tobacco product category. They are available in a variety of flavors and do not contain cut or ground tobacco leaf. The on!^® nicotine pouches fall within this category of OTDN products and are currently marketed in seven (7) flavors with five (5) different nicotine levels. Evaluation of the nicotine release from these products is valuable for product assessment and product-to-product comparisons. In this work, we characterized the in vitro release profiles of nicotine from the 35 varieties of on!^® nicotine pouches using a fit-for-purpose dissolution method, employing the U.S. Pharmacopeia flow-through cell dissolution apparatus 4 (USP-4). The nicotine release profiles were compared using the FDA’s Guidance for Industry: Dissolution Testing of Immediate Release Solid Oral Dosage Forms. The cumulative release profiles of nicotine show a dose dependent response for all nicotine levels. The on!^® nicotine pouches exhibit equivalent percent nicotine release rates for each flavor variant across all nicotine levels. Furthermore, the nicotine release profiles from on!^® nicotine pouches were compared to a variety of other commercially available OTDN pouches and traditional pouched smokeless tobacco products. The percent nicotine release rates were found to be dependent on the product characteristics, showing similarities and differences in the nicotine release profiles between the on!^® nicotine pouches and other compared products. Full article

(This article belongs to the Special Issue Method Development and Applications for Reduced-Risk Products in Separation Science)

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17 pages, 955 KiB

Open AccessArticle

Comparison of Neutral Compound Extraction from Archaeological Residues in Pottery Using Two Methodologies: A Preliminary Study

by Eleanora A. Reber

Separations 2021, 8(1), 6; https://doi.org/10.3390/separations8010006 - 6 Jan 2021

Cited by 4 | Viewed by 2949

Abstract

This study compares chloroform/methanol extraction and acidic methanol extraction of neutral compounds in absorbed lipid pottery residues from fourteen archaeological sherds. Previous studies have established that fatty acid extraction is more effective with acidic methanol extraction. This study suggests that acidic methanol extraction [...] Read more.

This study compares chloroform/methanol extraction and acidic methanol extraction of neutral compounds in absorbed lipid pottery residues from fourteen archaeological sherds. Previous studies have established that fatty acid extraction is more effective with acidic methanol extraction. This study suggests that acidic methanol extraction of neutral compounds, including sterols, alkanols, alkanes, and terpenoids, is more effective than or comparable to chloroform/methanol solvent extraction in most cases. The acidic methanol method extracts sterols, terpenoids, and alkanes more effectively than or comparably to chloroform/methanol extraction. Full article

(This article belongs to the Special Issue Analytical Chromatography Applied to Archaeology)

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14 pages, 1560 KiB

Open AccessArticle

Box-Behnken Assisted Validation and Optimization of an RP-HPLC Method for Simultaneous Determination of Domperidone and Lansoprazole

by Mohd Afzal, Mohd. Muddassir, Abdullah Alarifi and Mohammed Tahir Ansari

Separations 2021, 8(1), 5; https://doi.org/10.3390/separations8010005 - 6 Jan 2021

Cited by 11 | Viewed by 3642

Abstract

A highly specific, accurate, and simple RP-HPLC technique was developed for the real-time quantification of domperidone (DOMP) and lansoprazole (LANS) in commercial formulations. Chromatographic studies were performed using a Luna C8(2), 5 μm, 100Å, column (250 × 4.6 mm, Phenomenex) with a mobile [...] Read more.

A highly specific, accurate, and simple RP-HPLC technique was developed for the real-time quantification of domperidone (DOMP) and lansoprazole (LANS) in commercial formulations. Chromatographic studies were performed using a Luna C8(2), 5 μm, 100Å, column (250 × 4.6 mm, Phenomenex) with a mobile phase composed of acetonitrile/2 mM ammonium acetate (51:49 v/v), pH 6.7. The flow rate was 1 mL·min⁻¹ with UV detection at 289 nm. Linearity was observed within the range of 4–36 µg·mL⁻¹ for domperidone and 2–18 µg·mL⁻¹ for lansoprazole. Method optimization was achieved using Box-Behnken design software, in which three key variables were examined, namely, the flow rate (A), the composition of the mobile phase (B), and the pH (C). The retention time (Y₁ and Y₃) and the peak area (Y₂ and Y₄) were taken as the response parameters. We observed that slight alterations in the mobile phase and the flow rate influenced the outcome, whereas the pH exerted no effect. Method validation featured various ICH parameters including linearity, limit of detection (LOD), accuracy, precision, ruggedness, robustness, stability, and system suitability. This method is potentially useful for the analysis of commercial formulations and laboratory preparations. Full article

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30 pages, 1376 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Analysis of Monoclonal Antibodies by Capillary Electrophoresis: Sample Preparation, Separation, and Detection

by Meriem Dadouch, Yoann Ladner and Catherine Perrin

Separations 2021, 8(1), 4; https://doi.org/10.3390/separations8010004 - 4 Jan 2021

Cited by 31 | Viewed by 17221

Abstract

Therapeutic monoclonal antibodies (mAbs) are dominating the biopharmaceutical field due to the fact of their high specificity in the treatment of diverse diseases. Nevertheless, mAbs are very complex glycoproteins exhibiting several macro- and microheterogeneities that may affect their safety, quality, and efficacy. This [...] Read more.

Therapeutic monoclonal antibodies (mAbs) are dominating the biopharmaceutical field due to the fact of their high specificity in the treatment of diverse diseases. Nevertheless, mAbs are very complex glycoproteins exhibiting several macro- and microheterogeneities that may affect their safety, quality, and efficacy. This complexity is very challenging for mAbs development, formulation, and quality control. To tackle the quality issue, a combination of multiple analytical approaches is necessary. In this perspective, capillary electrophoresis has gained considerable interest over the last decade due to the fact of its complementary features to chromatographic approaches. This review provides an overview of the strategies of mAbs and derivatives analysis by capillary electrophoresis hyphenated to ultraviolet, fluorescence, and mass spectrometry detection. The main sample preparation approaches used for mAb analytical characterization (i.e., intact, middle-up/down, and bottom-up) are detailed. The different electrophoretic modes used as well as integrated analysis approaches (sample preparation and separation) are critically discussed. Full article

(This article belongs to the Special Issue Electrophoretic Methodologies for Protein Analysis)

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19 pages, 2963 KiB

Open AccessReview

Recent Advances in Microfluidics-Based Chromatography—A Mini Review

by Bo Bao, Zhichao Wang, Dilantha Thushara, Achini Liyanage, Sanja Gunawardena, Zaiyong Yang and Shuangliang Zhao

Separations 2021, 8(1), 3; https://doi.org/10.3390/separations8010003 - 31 Dec 2020

Cited by 21 | Viewed by 6897

Abstract

Microfluidics-based liquid chromatography is based on the miniaturization of the different types of liquid chromatography (LC) systems (e.g., affinity, adsorption, size exclusion, ion exchange) on a microchip to perform on-chip separation of different types of analytes. On-chip chromatography finds applications in genomics, proteomics, [...] Read more.

Microfluidics-based liquid chromatography is based on the miniaturization of the different types of liquid chromatography (LC) systems (e.g., affinity, adsorption, size exclusion, ion exchange) on a microchip to perform on-chip separation of different types of analytes. On-chip chromatography finds applications in genomics, proteomics, biomarker discovery, and environmental analysis. Microfluidics-based chromatography has good reproducibility and small sample consumption. However, the on-chip chromatography fabrication techniques are often more challenging to perform than conventional LC column preparation. Different research groups have attempted to develop different techniques to fabricate microfluidics-based LC systems. In this review, we will summarize the recent advances in microfluidics-based chromatography. Full article

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14 pages, 3660 KiB

Open AccessArticle

A New Cytotoxic Dimeric Sesquiterpene Isolated from Inula racemosa Hook. f. (Root): In Vitro and In Silico Analyses

by Rama Tyagi, Perwez Alam, Md. Tabish Rehman, Mohamed Fahad AlAjmi, Afzal Hussain, Saima Amin, Mohd. Mujeeb and Showkat R. Mir

Separations 2021, 8(1), 2; https://doi.org/10.3390/separations8010002 - 29 Dec 2020

Cited by 4 | Viewed by 3471

Abstract

A new dimeric sesquiterpene named disesquicin (compound 1) was isolated from Inula racemosa roots by normal-phase MPLC (Medium Pressure Liquid Chromatography), and its structure was established by using extensive spectral analysis. Compound 1, when tested on different human cancer cell lines, [...] Read more.

A new dimeric sesquiterpene named disesquicin (compound 1) was isolated from Inula racemosa roots by normal-phase MPLC (Medium Pressure Liquid Chromatography), and its structure was established by using extensive spectral analysis. Compound 1, when tested on different human cancer cell lines, showed marked cytotoxic activity (IC₅₀ (µg/mL): 5.99 (MDA-MB), 9.10 (HeLa), and 12.47 (A549)). Docking study revealed that it binds at the catalytic domain of PLK-1 and interacts with catalytic site residues Leu59, Gly60, Lys61, Gly62, Cys67, Ala80, Lys82, Leu130, Arg136, Ser137, Leu139, Glu140, Lys178, Gly180, Asn181, Phe183, and Asp194. The binding of compound 1 to PLK-1 is spontaneous in nature as evident by a free energy of—8.930 kcal mol⁻¹, corresponding to a binding affinity of 3.54 × 10⁶ M⁻¹. Results showed that compound 1 exhibited cytotoxic potential that was further confirmed by in vivo investigations. Full article

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14 pages, 3540 KiB

Open AccessArticle

Extraction of Natural Pigments from Gardenia Jasminoides J.Ellis Fruit Pulp Using CO₂-Expanded Liquids and Direct Sonication

by Hiroki Sakai, Kento Ono, Shinichi Tokunaga, Tanjina Sharmin, Taku Michael Aida and Kenji Mishima

Separations 2021, 8(1), 1; https://doi.org/10.3390/separations8010001 - 24 Dec 2020

Cited by 11 | Viewed by 3077

Abstract

In this work, a carbon dioxide-expanded liquid (CXL) extraction system was used with or without direct sonication for the extraction of highly polar natural pigments (crocin-1 and crocin-2) from Gardenia jasminoides Ellis fruit pulp. The effects of different parameters, including modifiers (ethanol, water, [...] Read more.

In this work, a carbon dioxide-expanded liquid (CXL) extraction system was used with or without direct sonication for the extraction of highly polar natural pigments (crocin-1 and crocin-2) from Gardenia jasminoides Ellis fruit pulp. The effects of different parameters, including modifiers (ethanol, water, aqueous ethanol), temperature (5–25 °C), pressure (8–14 MPa), and sonication time (0–200 s) on extraction concentrations were examined using the CXL system. Aqueous ethanol (50% or 80%, v/v) was selected for the CXL system as a modifier due to its efficiency. The best conditions for extraction were found at 25 °C and 10 MPa. The CXE 80% extraction system with direct sonication extracted a significantly higher amount of crocin-1 and crocin-2, 13.63 ± 0.5 and 0.51 ± 0.05 μg/mL, respectively, compared to conventional solid–liquid methanol extraction (10.43 ± 0.3 and 0.37 ± 0.02 μg/mL, respectively). Under these conditions, a water-rich phase, an ethanol-rich phase, and a CO₂-rich gas phase coexisted in the high-pressure cell in the CXE 80% extraction system, which was vigorously disrupted by the addition of sonication, resulting in a compressed aqueous ethanol phase and an aqueous ethanol-modified CO₂-rich phase, and may have a positive influence on extraction. Full article

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Separations, Volume 8, Issue 1 (January 2021) – 9 articles

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