Laser-Induced Graphene Electrodes Modified with a Molecularly Imprinted Polymer for Detection of Tetracycline in Milk and Meat

Tetracycline (TC) is a widely known antibiotic used worldwide to ‘’treat animals. Its residues in animal-origin foods cause adverse health effects to consumers. Low-cost and real-time measuring systems of TC in food samples are, therefore, extremely needed. In this work, a three-electrode sensitive and label-free sensor was developed to detect TC residues from milk and meat extract samples, using CO2 laser-induced graphene (LIG) electrodes modified with gold nanoparticles (AuNPs) and a molecularly imprinted polymer (MIP) used as a synthetic biorecognition element. LIG was patterned on a polyimide (PI) substrate, reaching a minimum sheet resistance (Rsh) of 17.27 ± 1.04 Ω/sq. The o-phenylenediamine (oPD) monomer and TC template were electropolymerized on the surface of the LIG working electrode to form the MIP. Surface morphology and electrochemical techniques were used to characterize the formation of LIG and to confirm each modification step. The sensitivity of the sensor was evaluated by differential pulse voltammetry (DPV), leading to a limit of detection (LOD) of 0.32 nM, 0.85 nM, and 0.80 nM in buffer, milk, and meat extract samples, respectively, with a working range of 5 nM to 500 nM and a linear response range between 10 nM to 300 nM. The sensor showed good LOD (0.32 nM), reproducibility, and stability, and it can be used as an alternative system to detect TC from animal-origin food products.

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CdTe0.5S0.5/ZnS Quantum Dots Embedded in a Molecularly Imprinted Polymer for the Selective Optosensing of Dopamine

Nanomaterials ◽

10.3390/nano9050693 ◽

2019 ◽

Vol 9 (5) ◽

pp. 693 ◽

Cited By ~ 2

Author(s):

Kiana Khadem-Abbassi ◽

Hervé Rinnert ◽

Lavinia Balan ◽

Zahra Doumandji ◽

Olivier Joubert ◽

...

Keyword(s):

Quantum Dots ◽

Ethylene Glycol ◽

Molecularly Imprinted Polymer ◽

Limit Of Detection ◽

Low Cost ◽

Core Shell ◽

Selective Detection ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Cross Linker

This work describes the preparation of molecularly imprinted polymer (MIP)-modified core/shell CdTe0.5S0.5/ZnS quantum dots (QDs). The QDs@MIP particles were used for the selective and sensitive detection of dopamine (DA). Acrylamide, which is able to form hydrogen bonds with DA, and ethylene glycol dimethylacrylate (EGDMA) as cross-linker were used for the preparation of the MIP. Highly cross-linked polymer particles with sizes up to 1 µm containing the dots were obtained after the polymerization. After the removal of the DA template, MIP-modified QDs (QDs@MIP) exhibit a high photoluminescence (PL) with an intensity similar to that of QDs embedded in the nonimprinted polymer (NIP). A linear PL decrease was observed upon addition of DA to QDs@MIP and the PL response was in the linear ranges from 2.63 µM to 26.30 µM with a limit of detection of 6.6 nM. The PL intensity of QDs@MIP was quenched selectively by DA. The QDs@MIP particles developed in this work are easily prepared and of low cost and are therefore of high interest for the sensitive and selective detection of DA in biological samples.

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A Novel Method for Extraction of Galegine by Molecularly Imprinted Polymer (MIP) Technique Reinforced with Graphene Oxide and Its Evaluation Using Polarography

Journal of Analytical Methods in Chemistry ◽

10.1155/2020/3646712 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

M. Azimi ◽

M. Ahmadi Golsefidi ◽

A. Varasteh Moradi ◽

M. Ebadii ◽

R. Zafar Mehrabian

Keyword(s):

Molecularly Imprinted Polymer ◽

Limit Of Detection ◽

Diabetes Type 2 ◽

Differential Pulse ◽

Template Molecule ◽

Imprinted Polymer ◽

Limit Of Quantification ◽

Molecularly Imprinted ◽

Galega Officinalis ◽

Relative Standard

Galega officinalis products have been used for the control of diabetes (type 2) across the world. Experimental and clinical evaluations of galegine substance produced by a medicinal plant (Galega officinalis) provided the pharmacological and chemical basis for metformin discovery which was confirmed for diabetes therapy. In this paper, the molecularly imprinted polymer (MIP) was synthesized for galegine, using galegine as a template molecule, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, azobisisobutyronitrile (AIBN) as a reaction initiator, and acetonitrile as a solvent. The assisted functional groups, morphology, topographic image of surface, and crystalline structure of synthesized MIP were characterized by FT-IR spectroscopy, field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) images, and XRD diffraction pattern techniques, respectively. Also, the performance of the mentioned electrode was quantified and qualified by the differential pulse voltammetry technique (DPV). The galegine amount was determined with the polarographic technique. In this research, the galegine extraction conditions were optimized and graphene nanoparticles were used to increase the adsorption. In addition, different parameters affecting extraction were investigated such as MIP adsorbent amount, pH of solution, effect of the surfactant, and ionic compound to achieve high recovery percent. The recovery percent, limit of detection (LOD), limit of quantification (LOQ), and relative standard deviation (RSD %) were 4.101 μg·mL−1, 12.427 μg·mL−1, and 1.199% (n = 3), respectively. The results show that the prepared MIP can be used as an effective and inexpensive adsorbent for preconcentration and galegine extraction from a natural sample. It is noteworthy that this developed method was used successfully to determine galegine extracted from Galega officinalis L.

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Protein Determination with Molecularly Imprinted Polymer Recognition Combined with Birefringence Liquid Crystal Detection

Sensors ◽

10.3390/s20174692 ◽

2020 ◽

Vol 20 (17) ◽

pp. 4692 ◽

Cited By ~ 1

Author(s):

Maciej Cieplak ◽

Rafał Węgłowski ◽

Zofia Iskierko ◽

Dorota Węgłowska ◽

Piyush S. Sharma ◽

...

Keyword(s):

Liquid Crystal ◽

Molecularly Imprinted Polymer ◽

Limit Of Detection ◽

Low Cost ◽

High Sensitivity ◽

Imprinted Polymer ◽

Optical Cell ◽

Protein Determination ◽

Molecularly Imprinted ◽

Nonspecific Interactions

Liquid crystal-based sensors offer the advantage of high sensitivity at a low cost. However, they often lack selectivity altogether or require costly and unstable biomaterials to impart this selectivity. To incur this selectivity, we herein integrated a molecularly imprinted polymer (MIP) film recognition unit with a liquid crystal (LC) in an optical cell transducer. We tested the resulting chemosensor for protein determination. We examined two different LCs, each with a different optical birefringence. That way, we revealed the influence of that parameter on the sensitivity of the (human serum albumin)-templated (MIP-HSA) LC chemosensor. The response of this chemosensor with the (MIP-HSA)-recognizing film was linear from 2.2 to 15.2 µM HSA, with a limit of detection of 2.2 µM. These values are sufficient to use the devised chemosensor for HSA determination in biological samples. Importantly, the imprinting factor (IF) of this chemosensor was appreciable, reaching IF = 3.7. This IF value indicated the predominant binding of the HSA through specific rather than nonspecific interactions with the MIP.

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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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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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Multibranched Gold–Mesoporous Silica Nanoparticles Coated with a Molecularly Imprinted Polymer for Label-Free Antibiotic Surface-Enhanced Raman Scattering Analysis

Chemistry of Materials ◽

10.1021/acs.chemmater.6b03613 ◽

2016 ◽

Vol 28 (21) ◽

pp. 7947-7954 ◽

Cited By ~ 44

Author(s):

Sergio Carrasco ◽

Elena Benito-Peña ◽

Fernando Navarro-Villoslada ◽

Judith Langer ◽

Marta N. Sanz-Ortiz ◽

...

Keyword(s):

Mesoporous Silica ◽

Raman Scattering ◽

Molecularly Imprinted Polymer ◽

Mesoporous Silica Nanoparticles ◽

Label Free ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering

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Molecularly Imprinted Polymer Based Sensors for Medical Applications

Sensors ◽

10.3390/s19061279 ◽

2019 ◽

Vol 19 (6) ◽

pp. 1279 ◽

Cited By ~ 41

Author(s):

Yeşeren Saylan ◽

Semra Akgönüllü ◽

Handan Yavuz ◽

Serhat Ünal ◽

Adil Denizli

Keyword(s):

Surface Modification ◽

Homeland Security ◽

Molecular Imprinting ◽

Molecularly Imprinted Polymer ◽

Structural Changes ◽

Low Cost ◽

Dimensional Structure ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Physical And Chemical

Sensors have been extensively used owing to multiple advantages, including exceptional sensing performance, user-friendly operation, fast response, high sensitivity and specificity, portability, and real-time analysis. In recent years, efforts in sensor realm have expanded promptly, and it has already presented a broad range of applications in the fields of medical, pharmaceutical and environmental applications, food safety, and homeland security. In particular, molecularly imprinted polymer based sensors have created a fascinating horizon for surface modification techniques by forming specific recognition cavities for template molecules in the polymeric matrix. This method ensures a broad range of versatility to imprint a variety of biomolecules with different size, three dimensional structure, physical and chemical features. In contrast to complex and time-consuming laboratory surface modification methods, molecular imprinting offers a rapid, sensitive, inexpensive, easy-to-use, and highly selective approaches for sensing, and especially for the applications of diagnosis, screening, and theranostics. Due to its physical and chemical robustness, high stability, low-cost, and reusability features, molecularly imprinted polymer based sensors have become very attractive modalities for such applications with a sensitivity of minute structural changes in the structure of biomolecules. This review aims at discussing the principle of molecular imprinting method, the integration of molecularly imprinted polymers with sensing tools, the recent advances and strategies in molecular imprinting methodologies, their applications in medical, and future outlook on this concept.

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A label-free biosensor based on graphene and reduced graphene oxide dual-layer for electrochemical determination of beta-amyloid biomarkers

Microchimica Acta ◽

10.1007/s00604-020-04267-x ◽

2020 ◽

Vol 187 (5) ◽

Cited By ~ 4

Author(s):

Jagriti Sethi ◽

Michiel Van Bulck ◽

Ahmed Suhail ◽

Mina Safarzadeh ◽

Ana Perez-Castillo ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Limit Of Detection ◽

Electrochemical Techniques ◽

Differential Pulse ◽

Electrochemical Determination ◽

Label Free ◽

Reduced Graphene ◽

Electrochemically Reduced Graphene Oxide

AbstractA label-free biosensor is developed for the determination of plasma-based Aβ1–42 biomarker in Alzheimer’s disease (AD). The platform is based on highly conductive dual-layer of graphene and electrochemically reduced graphene oxide (rGO). The modification of dual-layer with 1-pyrenebutyric acid N-hydroxysuccinimide ester (Pyr-NHS) is achieved to facilitate immobilization of H31L21 antibody. The effect of these modifications were studied with morphological, spectral and electrochemical techniques. The response of the biosensor was evaluated using differential pulse voltammetry (DPV). The data was acquired at a working potential of ~ 180 mV and a scan rate of 50 mV s−1. A low limit of detection (LOD) of 2.398 pM is achieved over a wide linear range from 11 pM to 55 nM. The biosensor exhibits excellent specificity over Aβ1–40 and ApoE ε4 interfering species. Thus, it provides a viable tool for electrochemical determination of Aβ1–42. Spiked human and mice plasmas were used for the successful validation of the sensing platform in bio-fluidic samples. The results obtained from mice plasma analysis concurred with the immunohistochemistry (IHC) and magnetic resonance imaging (MRI) data obtained from brain analysis.

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