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Chemosensors
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Chemical and Biosensors Based on Metal-Organic Frames (MOFs)
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Chemical and Biosensors Based on Metal-Organic Frames (MOFs)

A special issue of Chemosensors (ISSN 2227-9040). This special issue belongs to the section "Materials for Chemical Sensing".

Deadline for manuscript submissions: closed (31 August 2024) | Viewed by 14384

Special Issue Editors

Prof. Dr. Chunsheng Wu

E-Mail Website
Guest Editor
Institute of Medical Engineering, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an 710061, China
Interests: cell- and molecule-based biosensors; DNA biosensors; microfluidic chips; molecular diagnostics; micro/nano devices for chemical sensing; electrochemical sensors
Special Issues, Collections and Topics in MDPI journals
Dr. Liping Du

E-Mail Website
Guest Editor
Institute of Medical Engineering, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an 710061, China
Interests: chemical sensors; biomimetic olfactory biosensors; odor discrimination; bioelectronic nose; olfac-tory organoid
Special Issues, Collections and Topics in MDPI journals
Dr. Wei Chen

E-Mail Website
Guest Editor
Institute of Medical Engineering, School of Basic Medical Sciences, Xi’an Jiaotong University, Xi’an 710061, China
Interests: MOFs; aptamer; PAMAM dendrimer; nanomaterials-based biosensors; polymer composites; electrospinning; cellulose; conductive polymer
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Metal–organic frameworks (MOFs) provide unprecedented opportunities for the development of novel biosensors due to their decisive advantages, such as a large surface area, high porosity, tunable structures, and flexibility regarding tailored properties. Sensitive elements could be coupled to MOFs in situ through adding bioactive molecules during the synthesis process of MOFs. In addition, the tunable size and large surface area and channels of various sizes make MOFs ideal platforms for constructing hybrid composite materials that are suitable for use as sensitive elements in chemical and biosensing. The applications of MOFs in chemicals and biosensors have attracted increasing attention, which has led to novel structures and features in MOF-based chemical and biosensors, such as a higher stability, higher sensitivity, higher flexibility, and higher specificity. This Special Issue will provide a forum for the latest research activities in the field of MOF-based chemicals and biosensors, with an emphasis on the relevant synthesis and modification of MOFs and their applications. Both review articles and original research papers are solicited in the following areas, among others:

  • Design and synthesis of MOFs for chemosensors;
  • Design and synthesis of MOFs for biosensors;
  • Electrochemical sensors based on MOFs;
  • Colorimetric sensors based on MOFs;
  • Photoelectrochemical sensors based on MOFs;
  • Fluorescent sensors based on MOFs;
  • Electrochemiluminescence sensors based on MOFs.

Prof. Dr. Chunsheng Wu
Dr. Liping Du
Dr. Wei Chen
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Chemosensors is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

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Published Papers (10 papers)

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Research

16 pages, 4413 KiB  
Article
Metal–Organic Framework-Derived CeO2/Gold Nanospheres in a Highly Sensitive Electrochemical Sensor for Uric Acid Quantification in Milk
by Miloš Ognjanović, Milena Marković, Vladimír Girman, Vladimir Nikolić, Sanja Vranješ-Đurić, Dalibor M. Stanković and Branka B. Petković
Chemosensors 2024, 12(11), 231; https://doi.org/10.3390/chemosensors12110231 - 3 Nov 2024
Viewed by 798
Abstract
In this work, CeBTC (a cerium(III) 1,3,5-benzene-tricarboxylate), was used as a precursor for obtaining CeO2 nanoparticles (nanoceria) with better sensor performances than CeO2 nanoparticles synthesized by the solvothermal method. Metal–organic framework-derived nanoceria (MOFdNC) were functionalized with spheric gold nanoparticles (AuNPs) to [...] Read more.
In this work, CeBTC (a cerium(III) 1,3,5-benzene-tricarboxylate), was used as a precursor for obtaining CeO2 nanoparticles (nanoceria) with better sensor performances than CeO2 nanoparticles synthesized by the solvothermal method. Metal–organic framework-derived nanoceria (MOFdNC) were functionalized with spheric gold nanoparticles (AuNPs) to further improve non-enzymatic electrode material for highly sensitive detection of prominent biocompound uric acid (UA) at this modified carbon paste electrode (MOFdNC/AuNPs&CPE). X-ray powder diffraction (XRPD) and transmission electron microscopy (TEM) analysis were used for morphological structure characterization of the obtained nanostructures. Cyclic voltammetry and electrochemical impedance spectroscopy, both in an [Fe(CN)6]3−/4− redox system and uric acid standard solutions, were used for the characterization of material electrocatalytic performances, the selection of optimal electrode modifier, and the estimation of nature and kinetic parameters of the electrode process. Square-wave voltammetry (SWV) was chosen, and the optimal parameters of technique and experimental conditions were established for determining uric acid over MOFdNC/AuNPs&CPE. Together with the development of the sensor, the detection procedure was optimized with the following analytical parameters: linear operating ranges of 0.05 to 1 µM and 1 to 50 µM and a detection limit of 0.011 µM, with outstanding repeatability, reproducibility, and stability of the sensor surface. Anti-interference experiments yielded a stable and nearly unchanged current response with negligible or no change in peak potential. After minor sample pretreatment, the proposed electrode was successfully applied for the quantification of UA in milk. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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15 pages, 4857 KiB  
Article
Paper-Based Analytical Devices Based on Amino-MOFs (MIL-125, UiO-66, and MIL-101) as Platforms towards Fluorescence Biodetection Applications
by Sofía V. Piguillem, Germán E. Gomez, Gonzalo R. Tortella, Amedea B. Seabra, Matías D. Regiart, Germán A. Messina and Martín A. Fernández-Baldo
Chemosensors 2024, 12(10), 208; https://doi.org/10.3390/chemosensors12100208 - 11 Oct 2024
Viewed by 836
Abstract
In this study, we designed three promising platforms based on metal–organic frameworks (MOFs) to develop paper-based analytical devices (PADs) for biosensing applications. PADs have become increasingly popular in field sensing in recent years due to their portability, low cost, simplicity, efficiency, fast detection [...] Read more.
In this study, we designed three promising platforms based on metal–organic frameworks (MOFs) to develop paper-based analytical devices (PADs) for biosensing applications. PADs have become increasingly popular in field sensing in recent years due to their portability, low cost, simplicity, efficiency, fast detection capability, excellent sensitivity, and selectivity. In addition, MOFs are excellent choices for developing highly sensitive and selective sensors due their versatility for functionalizing, structural stability, and capability to adsorb and desorb specific molecules by reversible interactions. These materials also offer the possibility to modify their structure and properties, making them highly versatile and adaptable to different environments and sensing needs. In this research, we synthesized and characterized three different amino-functionalized MOFs: UiO-66-NH2 (Zr), MIL-125-NH2 (Ti), and MIL-101-NH2 (Fe). These MOFs were used to fabricate PADs capable of sensitive and portable monitoring of alkaline phosphatase (ALP) enzyme activity by laser-induced fluorescence (LIF). Overall, amino-derivated MOF platforms demonstrate significant potential for integration into biosensor PADs, offering key properties that enhance their performance and applicability in analytical chemistry and diagnostics. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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12 pages, 2670 KiB  
Article
A Zinc Oxide Nanorod-Based Electrochemical Aptasensor for the Detection of Tumor Markers in Saliva
by Junrong Li, Yihao Ding, Yuxuan Shi, Zhiying Liu, Jun Lin, Rui Cao, Miaomiao Wang, Yushuo Tan, Xiaolin Zong, Zhan Qu, Liping Du and Chunsheng Wu
Chemosensors 2024, 12(10), 203; https://doi.org/10.3390/chemosensors12100203 - 2 Oct 2024
Viewed by 710
Abstract
Biosensors have emerged as a promising tool for the early detection of oral squamous cell carcinoma (OSCC) due to their rapid, sensitive, and specific detection of cancer biomarkers. Saliva is a non-invasive and easy-to-obtain biofluid that contains various biomarkers of OSCC, including the [...] Read more.
Biosensors have emerged as a promising tool for the early detection of oral squamous cell carcinoma (OSCC) due to their rapid, sensitive, and specific detection of cancer biomarkers. Saliva is a non-invasive and easy-to-obtain biofluid that contains various biomarkers of OSCC, including the carcinoembryonic antigen (CEA). In this study, an electrochemical aptasensor for the detection of CEA in saliva has been developed towards the diagnosis and early screening of OSCC. This aptasensor utilized a CEA-sensitive aptamer as sensitive elements. A fluorine-doped Tin Oxide (FTO) chip with a surface modification of a zinc oxide nanorod was employed as a transducer. Electrochemical measurements were carried out to detect the responsive signals originating from the specific binding between aptamers and CEAs. The measurement results indicated that this aptasensor was responsive to different concentrations of CEA ranging from 1 ng/mL to 80 ng/mL in a linear relationship. The limit of detection (LOD) was 0.75 ng/mL. This aptasensor also showed very good specificity and regenerative capability. Stability testing over a 12-day period showed excellent performance of this aptasensor. All the results demonstrated that this aptasensor has great potential to be used for the detection of CEA in the saliva of OSCC patients. This aptasensor provides a promising method for the rapid detection of CEA with convenience, which has great potential to be used as a new method for clinical diagnoses and early screening of OSCC. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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14 pages, 5745 KiB  
Article
The Efficient and Sensitive Detection of Serum Dopamine Based on a MOF-199/Ag@Au Composite SERS Sensing Structure
by Yuyu Peng, Chunyan Wang, Gen Li, Jianguo Cui, Yina Jiang, Xiwang Li, Zhengjie Wang and Xiaofeng Zhou
Chemosensors 2024, 12(9), 187; https://doi.org/10.3390/chemosensors12090187 - 13 Sep 2024
Viewed by 817
Abstract
In this study, a MOF-199/Ag@Au SERS sensing structure was successfully synthesized by combining metal–organic frameworks (MOFs) with surface-enhanced Raman scattering (SERS) technology for the efficient detection of dopamine (DA), a biomarker for neurological diseases, in serum. Using electrochemical methods, a copper-based MOF (MOF-199) [...] Read more.
In this study, a MOF-199/Ag@Au SERS sensing structure was successfully synthesized by combining metal–organic frameworks (MOFs) with surface-enhanced Raman scattering (SERS) technology for the efficient detection of dopamine (DA), a biomarker for neurological diseases, in serum. Using electrochemical methods, a copper-based MOF (MOF-199) was synthesized in situ on copper substrates and further deposited with silver nanoparticles (AgNPs). Subsequently, gold nanoshells were encapsulated around these silver cores by in situ chemical deposition. This preparation process is simple, controllable, and inexpensive. Furthermore, a novel Azo reaction-based DA SERS method was proposed to detect 1 pM DA, which represents an improvement in sensitivity by two orders of magnitude compared to previous unlabeled SERS detection methods and by four orders of magnitude compared to another SERS approach proposed in this work. There was an excellent linear relationship (R2 = 0.976) between the SERS signal at 1140 cm−1 and the DA concentration (0.001 M~1 pM). The results indicate that the MOF-199/Ag@Au sensor structure can successfully achieve both the qualitative and quantitative detection of DA in serum, thus providing a robust technical basis for the application of SERS technology in the field of clinical neurological disease screening. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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17 pages, 5228 KiB  
Article
A Host–Guest Platform for Highly Efficient, Quantitative, and Rapid Detection of Nitroreductase
by Wen Si, Yang Jiao, Xianchao Jia, Meng Gao, Yihao Zhang, Ye Gao, Lei Zhang and Chunying Duan
Chemosensors 2024, 12(8), 145; https://doi.org/10.3390/chemosensors12080145 - 30 Jul 2024
Viewed by 869
Abstract
Nitroreductase (NTR) is an enzyme expressed at an abnormally high level in solid tumors, which is associated with the hypoxia level in tumors. The establishment of a high-performance and convenient fluorescent platform for the fast monitoring of NTR is of pivotal importance. Herein, [...] Read more.
Nitroreductase (NTR) is an enzyme expressed at an abnormally high level in solid tumors, which is associated with the hypoxia level in tumors. The establishment of a high-performance and convenient fluorescent platform for the fast monitoring of NTR is of pivotal importance. Herein, a novel host–guest complex was created by encapsulating a fluorescent substrate GP-NTR within a metal–organic capsule Zn-MPB that included a NADH mimic for the detection of hypoxia via responding to nitroreductase (NTR) with fast responsiveness and good fluorescence imaging. Notably, the double-substrate process was streamlined to a single–substrate process by the host–guest supramolecular method in the catalytic process of NTR, which enabled the reaction to be independent of the cofactor NADH supply and shortened the distance between the substrate and the active site of NTR. The increasing fluorescence intensity of Zn-MPB⊃GP-NTR exhibits a linear relationship with NTR concentration and shows a fast response toward NTR in solution in tens of seconds. Zn-MPB⊃GP-NTR also displays high sensitivity to NTR with a low detection limit of 6.4 ng/mL. Cells and in vivo studies have confirmed that Zn-MPB⊃GP-NTR could be successfully applied for the fast imaging of NTR in NTR-overexpressed tumor cells and tumor-bearing animals. The host–guest platform not only provides a new avenue for the design and optimization of a fluorescence detection platform for the rapid and quantitative detection of NTR activity, but also offers an imaging tool for the early diagnosis of hypoxia-related tumors. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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15 pages, 5019 KiB  
Article
Bipyridyl Ruthenium-Decorated Ni-MOFs on Carbon Nanotubes for Electrocatalytic Oxidation and Sensing of Glucose
by Yu Zhang, Chang Liu, Rongqiu Yan and Chenghong Lei
Chemosensors 2024, 12(3), 39; https://doi.org/10.3390/chemosensors12030039 - 4 Mar 2024
Viewed by 1559
Abstract
Bipyridyl Ruthenium-decorated Ni-MOFs on multi-walled carbon nanotubes (MWCNT-RuBpy@Ni-MOF) were synthesized. In an alkaline solution, the glucose was electrocatalytically oxidized at +0.5 V vs. Ag/AgCl at the composite interface of MWCNT-RuBpy@Ni-MOF on a glassy carbon electrode. The Ni3+/Ni2+ redox couples in [...] Read more.
Bipyridyl Ruthenium-decorated Ni-MOFs on multi-walled carbon nanotubes (MWCNT-RuBpy@Ni-MOF) were synthesized. In an alkaline solution, the glucose was electrocatalytically oxidized at +0.5 V vs. Ag/AgCl at the composite interface of MWCNT-RuBpy@Ni-MOF on a glassy carbon electrode. The Ni3+/Ni2+ redox couples in Ni-MOFs played a key role as the active center for the catalytic oxidation of glucose at the electrode, where both RuBpy and MWCNTs enhanced the current responses to glucose. The resulting enzymeless glucose sensor from MWCNT-RuBpy@Ni-MOF exhibited a wide range of linear responses, high sensitivity and selectivity for the determination of glucose. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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12 pages, 2049 KiB  
Article
Pyrene-Derived Covalent Organic Framework Films: Advancements in Acid Vapor Detection
by Shaikha S. AlNeyadi, Mohammed T. Alhassani, Ali S. Aleissaee and Ibrahim AlMujaini
Chemosensors 2024, 12(3), 37; https://doi.org/10.3390/chemosensors12030037 - 3 Mar 2024
Viewed by 1634
Abstract
The expansion of global industry results in the release of harmful volatile acid vapors into the environment, posing a threat to various lifeforms. Hence, it is crucial to prioritize the development of swift sensing systems capable of monitoring these volatile acid vapors. This [...] Read more.
The expansion of global industry results in the release of harmful volatile acid vapors into the environment, posing a threat to various lifeforms. Hence, it is crucial to prioritize the development of swift sensing systems capable of monitoring these volatile acid vapors. This initiative holds great importance in safeguarding a clean and safe environment. This paper presents the synthesis and characterization of pyrene-based covalent organic frameworks (COFs) that exhibit exceptional crystallinity, thermal stability, and intense fluorescence. Three COFs—PP–COF, PT–COF, and PE–COF—were synthesized, demonstrating large surface areas and robust thermal stability up to 400 °C. The fluorescence properties and intramolecular charge transfer within these COFs were significantly influenced by their Schiff base bonding types and π-stacking degrees between COF layers. Notably, PE-COF emerged as the most fluorescent of the three COFs and exhibited exceptional sensitivity and rapid response as a fluorescent chemosensor for detecting HCl in solution. The reversible protonation of imine bonds in these COFs allowed for the creation of highly sensitive acid vapor sensors, showcasing a shift in spectral absorption while maintaining structural integrity. This study highlights the potential of COFs as reliable and reusable sensors for detecting harmful acid vapors and addressing environmental concerns arising from industrial activities. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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12 pages, 3959 KiB  
Communication
Preparation and Enhanced Acetone-Sensing Properties of ZIF-8-Derived Co3O4@ZnO Microspheres
by Xiangxiang Fan, Susu Yang, Chun Huang, Yujie Lu and Pan Dai
Chemosensors 2023, 11(7), 376; https://doi.org/10.3390/chemosensors11070376 - 5 Jul 2023
Cited by 9 | Viewed by 1559
Abstract
In this work, ZIF-8-derived Co3O4@ZnO microspheres were prepared by a liquid-phase concentration-controlled nucleation strategy. The results of the material characterization showed that Co3O4@ZnO microspheres were obtained, and the surface structure could be controlled with the [...] Read more.
In this work, ZIF-8-derived Co3O4@ZnO microspheres were prepared by a liquid-phase concentration-controlled nucleation strategy. The results of the material characterization showed that Co3O4@ZnO microspheres were obtained, and the surface structure could be controlled with the concentration of the ligand. Compared with pure Co3O4 microspheres, the operating temperature of optimized Co3O4@ZnO microspheres increased by 90 °C after the gas-sensing test. The response to 50 ppm acetone of Co3O4@ZnO microspheres was 4.5 times higher than that of pure Co3O4, and the detection limit reached 0.5 ppm. Meanwhile, Co3O4@ZnO microspheres showed a shorter response-recovery time and better selectivity. The enhanced-sensing mechanism of the ZIF-8-derived Co3O4@ZnO microspheres was also analyzed. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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11 pages, 1585 KiB  
Communication
Dual-Response Photofunctional Covalent Organic Framework for Acid Detection in Various Solutions
by Wenyue Ma, Zijian Gu, Guocui Pan, Chunjuan Li, Yu Zhu, Zhaoyang Liu, Leijing Liu, Yupeng Guo, Bin Xu and Wenjing Tian
Chemosensors 2023, 11(4), 214; https://doi.org/10.3390/chemosensors11040214 - 30 Mar 2023
Viewed by 1779
Abstract
The detection of acid in different solution environments plays a significant role in chemical, environmental and biological fields. However, reducing the constraints of detecting environment, such as aqueous, organic solvents and mixed phases of aqueous and organic phases, remains a challenge. Herein, by [...] Read more.
The detection of acid in different solution environments plays a significant role in chemical, environmental and biological fields. However, reducing the constraints of detecting environment, such as aqueous, organic solvents and mixed phases of aqueous and organic phases, remains a challenge. Herein, by combining N, N, N′, N′-tetrakis(4-aminophenyl)-1,4-phenylenediamine (TPBD) and terephthalaldehyde (TA) via Shiff-base condensation, we constructed a covalent organic framework (COF) TPBD-TA COF. The COF exhibits color change from red to dark red as well as fluorescence quenching with the increase of acid contents in either aqueous or organic solvents, or a mixture of aqueous and organic solvents, due to the weak donor-acceptor interactions within the COF as well as the weak proton ionization ability of the solutions. Therefore, regardless of the detection environment, TPBD-TA COF can realize color and fluorescence dual-response to acid with the detection limit as low as 0.4 μmol/L and 58 nmol/L, respectively, due to the protonation of the nitrogen atoms on imine bonds of the COF. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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18 pages, 4489 KiB  
Article
Facile Electrochemical Approach Based on Hydrogen-Bonded MOFs-Derived Tungsten Ethoxide/Polypyrrole-Reduced GO Nanocrystal for ppb Level Ammonium Ions Detection
by Sara Maira Mohd Hizam and Mohamed Shuaib Mohamed Saheed
Chemosensors 2023, 11(3), 201; https://doi.org/10.3390/chemosensors11030201 - 21 Mar 2023
Viewed by 1856
Abstract
Ammonium (NH4+) ions are a primary contaminant in the river and along the waterside near an agricultural area, therefore, necessitating sensitive detection of pollutants before irreversibly damaging environment. Herein, a new approach of metal-organic framework-derived tungsten ethoxide/polypyrrole-reduced graphene oxide (MOFs-W(OCH [...] Read more.
Ammonium (NH4+) ions are a primary contaminant in the river and along the waterside near an agricultural area, therefore, necessitating sensitive detection of pollutants before irreversibly damaging environment. Herein, a new approach of metal-organic framework-derived tungsten ethoxide/polypyrrole-reduced graphene oxide (MOFs-W(OCH2CH3)6/Ppy-rGO) electrochemical sensors are introduced. Through a simple hydrothermal process, Ppy-rGO is linked to tungsten ethoxide as an organic linker. This creates the MOFs-W(OCH2CH3)6/Ppy-rGO nanocrystal through hydrogen bonding. The synergistic combination of tungsten ethoxide and Ppy-rGO provides three-fold advantages: stabilization of Ppy-rGO for extended usage, enabling detection of analytes at ambient temperature, and availability of multiple pathways for effective detection of analytes. This is demonstrated through excellent detection of NH4+ ions over a dynamic concentration range of 0.85 to 3.35 µM with a ppb level detection limit of 0.278 µM (9.74 ppb) and a quantitation limit of 0.843 µM (29.54 ppb). The increment in the concentration of NH4+ ions contributes to the increment in proton (H+) concentration. The increment in proton concentration in the solution will increase the bonding activity and thus increase the conductivity. The cyclic voltammetry curves of all concentrations of NH4+ analytes at the operating potential window between −1.5 and 1.5 V exhibit a quasi-rectangular shape, indicating consistent electronic and ionic transport. The distinctive resistance changes of the MOFs-W(OCH2CH3)6/Ppy-rGO to various NH4+ ion concentrations and ultrasensitive detection provide an extraordinary platform for its application in the agriculture industry. Full article
(This article belongs to the Special Issue Chemical and Biosensors Based on Metal-Organic Frames (MOFs))
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