Electrochemical Sensor Based on Molecularly Imprinted Polymer for the Detection of Cefalexin

In this study, a new electrochemical sensor was developed for the detection of cefalexin (CFX), based on the use of a molecularly imprinted polymer (MIP) obtained by electro‒polymerization in an aqueous medium of indole-3-acetic acid (I3AA) on a glassy carbon electrode (GCE) and on boron-doped diamond electrode (BDDE). The two different electrodes were used in order to assess how their structural differences and the difference in the potential applied during electrogeneration of the MIP translate to the performances of the MIP sensor. The quantification of CFX was performed by using the electrochemical signal of a redox probe before and after the rebinding of the template. The modified electrode was characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The influence of different parameters on the fabrication of the sensor was tested, and the optimized method presented high selectivity and sensitivity. The MIP-based electrode presented a linear response for CFX concentration range of 10 to 1000 nM, and a limit of detection of 3.2 nM and 4.9 nM was obtained for the BDDE and the GCE, respectively. The activity of the sensor was successfully tested in the presence of some other cephalosporins and of other pharmaceutical compounds. The developed method was successfully applied to the detection of cefalexin from real environmental and pharmaceutical samples.

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Detection of dopamine by a minimized electrochemical sensor using a graphene oxide molecularly imprinted polymer modified micropipette tip shaped graphite electrode

Journal of Chemical Research ◽

10.1177/1747519821989957 ◽

2021 ◽

pp. 174751982198995

Author(s):

Yi Wang ◽

Jianshe Tang ◽

Li Xiang

Keyword(s):

Graphene Oxide ◽

Electrochemical Sensor ◽

Molecularly Imprinted Polymer ◽

Carbon Paste Electrode ◽

Limit Of Detection ◽

Carbon Paste ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Paste Electrode

A simple and efficient electrochemical sensor based on a homemade reshaped micropipette tip carbon paste electrode is reported. Molecularly imprinted polymer membranes of graphene oxide and polypyrrole are synthesized and modified on the surface of micropipette tip carbon paste electrode. The merit of the method is evaluated under optimized conditions via differential pulse voltammetrics. The prepared sensor exhibits remarkable sensitivity toward dopamine with a linear range of 6.4 × 10−8–2 × 10−4 M, with a limit of detection as low as 1 × 10−8 M. The proposed method is applied for the determination of dopamine in urine samples by the standard addition route. A range of 1 × 10−7–1 × 10−4 M is obtained from these samples. The relative recoveries are in the range of 95.2%–104%. The proposed method has acceptable performance for the determination of dopamine in real samples with excellent sensitivity and selectivity.

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An electrochemical sensor for the determination of phoxim based on a graphene modified electrode and molecularly imprinted polymer

Analytical Methods ◽

10.1039/c5ay00945f ◽

2015 ◽

Vol 7 (11) ◽

pp. 4786-4792 ◽

Cited By ~ 13

Author(s):

Xuecai Tan ◽

Jiawen Wu ◽

Qi Hu ◽

Xiaoyu Li ◽

Pengfei Li ◽

...

Keyword(s):

Electrochemical Sensor ◽

Modified Electrode ◽

Molecularly Imprinted Polymer ◽

Electrochemical Impedance ◽

Impedance Spectra ◽

Imprinted Polymer ◽

Electrochemical Impedance Spectra ◽

Molecularly Imprinted

The electrochemical impedance spectra of Fe(CN)63−/4− at NIP/graphene/GCE (a), MIP/GCE (b), the bare GCE (c), and MIP/graphene/GCE (d).

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Liquid Chromatography Analysis of Clozapine in Rat Brain Tissue, Using its Molecularly Imprinted Polymer after Administration of Toxic Dose of Drug and Lipid Emulsion Therapy

Current Pharmaceutical Analysis ◽

10.2174/1573412914666180111160741 ◽

2019 ◽

Vol 15 (3) ◽

pp. 251-257

Author(s):

Bahareh Sadat Yousefsani ◽

Seyed Ahmad Mohajeri ◽

Mohammad Moshiri ◽

Hossein Hosseinzadeh

Keyword(s):

Rat Brain ◽

Brain Tissue ◽

Molecularly Imprinted Polymer ◽

Lipid Emulsion ◽

Limit Of Detection ◽

Imprinted Polymer ◽

Toxic Dose ◽

Molecularly Imprinted ◽

The Brain ◽

Rat Brain Tissue

Background:Molecularly imprinted polymers (MIPs) are synthetic polymers that have a selective site for a given analyte, or a group of structurally related compounds, that make them ideal polymers to be used in separation processes.Objective:An optimized molecularly imprinted polymer was selected and applied for selective extraction and analysis of clozapine in rat brain tissue.Methods:A molecularly imprinted solid-phase extraction (MISPE) method was developed for preconcentration and cleanup of clozapine in rat brain samples before HPLC-UV analysis. The extraction and analytical process was calibrated in the range of 0.025-100 ppm. Clozapine recovery in this MISPE process was calculated between 99.40 and 102.96%. The limit of detection (LOD) and the limit of quantification (LOQ) of the assay were 0.003 and 0.025 ppm, respectively. Intra-day precision values for clozapine concentrations of 0.125 and 0.025 ppm were 5.30 and 3.55%, whereas inter-day precision values of these concentrations were 9.23 and 6.15%, respectively. In this study, the effect of lipid emulsion infusion in reducing the brain concentration of drug was also evaluated.Results:The data indicated that calibrated method was successfully applied for the analysis of clozapine in the real rat brain samples after administration of a toxic dose to animal. Finally, the efficacy of lipid emulsion therapy in reducing the brain tissue concentration of clozapine after toxic administration of drug was determined.Conclusion:The proposed MISPE method could be applied in the extraction and preconcentration before HPLC-UV analysis of clozapine in rat brain tissue.

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An electrochemical sensor based on molecularly imprinted polymer conjointly with a voltammetric electronic tongue for quantitative diphenyl phosphate detection in urine samples from cosmetic product users

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2021.129449 ◽

2021 ◽

pp. 129449

Author(s):

Soukaina Motia ◽

Benachir Bouchikhi ◽

Nezha El Bari

Keyword(s):

Electrochemical Sensor ◽

Molecularly Imprinted Polymer ◽

Electronic Tongue ◽

Urine Samples ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Cosmetic Product ◽

Diphenyl Phosphate ◽

Voltammetric Electronic Tongue ◽

Phosphate Detection

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A Molecularly Imprinted Polymer for Selective Extraction of Phenolic Acids from Human Urine

Applied Sciences ◽

10.3390/app11041577 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1577

Author(s):

Marco Mora-Granados ◽

David González-Gómez ◽

Jin Su Jeong ◽

Alejandrina Gallego-Picó

Keyword(s):

Phenolic Acids ◽

Molecularly Imprinted Polymer ◽

Human Urine ◽

Limit Of Detection ◽

Ph Dependence ◽

Selective Extraction ◽

Screening Methods ◽

Specific Method ◽

Imprinted Polymer ◽

Molecularly Imprinted

Studies for monitoring the bioavailability of dietary flavonoid compounds generate great interest. Among them, low-molecular-weight phenolic acids, secondary metabolites present in colonic catabolism and urinary excretion, have been proposed as biomarkers of polyphenol intake. Using 4-hydroxyphenylacetic acid as a template, a molecularly imprinted polymer (MIP) was synthesized for selective extraction of these hydroxylated metabolites from human urine samples and posterior analysis in an HPLC-DAD-MS system. Polymers were characterized by Scanning electron microscopy (SEM), Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), Brunauer-Emmett-Teller (BET) method, and binding experiments. MIP presents specific recognition ability for template and analogues molecules. This capacity of recognition and the pH dependence of the binding strength was also studied. The method was validated over a concentration range of 0.25–40 mg/L, r2 > 0.995. In the optimized conditions, the recovery value was 94% with RSD 1.2%. The Limit of Detection (LOD) and Limit of Quantification (LOQ) were 1.22 and 3.69 mg/L, respectively. In our knowledge, it is the first time that this methodology is applied to analyze urinary catabolites of the polyphenol compound and to provide a specific method and simple analysis alternative. The selective extraction of these metabolites improves the application and results obtained by other less sensitive analysis methods than the validation method. It also facilitates the development of new screening methods.

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