Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Fast Determination of Vitamin B2 Based on Molecularly Imprinted Electrochemical Sensor  [PDF]
Peidong Xu, Changsheng Qiao, Shufeng Yang, Lijuan Liu, Mingwei Wang, Juankun Zhang
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.410B034
Under the condition of weak acidity of pH 5.2, a sensitive vitamin B2 electrochemical sensor based on molecularly imprinted nonconducting polymer of o-aminophenol by potentiostatic polymerization in the presence of template(vitamin B2) on a glassy carbon electrode was prepared, and its performance was studied. The sensor exhibited good sensitivity and selectivity to VB2. The detection limit went down to 2.3851nM, and a linear relationship between the current incremental and the concentration was found in the range of 10~120nM. And the sensor could use in detection of VB2 real sample for a long time and show good reproducibility. The average recovery rate to VB2 was 98.41%.
A Molecularly Imprinted Polymer with Incorporated Graphene Oxide for Electrochemical Determination of Quercetin  [PDF]
Si Sun,Mengqi Zhang,Yijun Li,Xiwen He
Sensors , 2013, DOI: 10.3390/s130505493
Abstract: The molecularly imprinted polymer based on polypyrrole film with incorporated graphene oxide was fabricated and used for electrochemical determination of quercetin. The electrochemical behavior of quercetin on the modified electrode was studied in detail using differential pulse voltammetry. The oxidation peak current of quercetin in B-R buffer solution (pH = 3.5) at the modified electrode was regressed with the concentration in the range from 6.0 × 10 ?7 to 1.5 × 10 ?5 mol/L (r 2 = 0.997) with a detection limit of 4.8 × 10 ?8 mol/L (S/N = 3). This electrode showed good stability and reproducibility. In the above mentioned range, rutin or morin which has similar structures and at the same concentration as quercetin did not interfere with the determination of quercetin. The applicability of the method for complex matrix analysis was also evaluated.
The Establishment of Bisphenol A Sensing System Utilizing Molecularly Imprinted Polymer Receptor and Electrochemical Determination
Izumi Kubo,Nobuyuki Yokota,Yuko Nakane,Yusuke Fuchiwaki
International Journal of Electrochemistry , 2011, DOI: 10.4061/2011/534936
Abstract: A sensing system of bisphenol A (BPA) based on the electrochemical detection utilizing molecularly imprinted polymer (MIP) as a receptor of BPA was investigated. MIP for BPA was polymerized thermally from 4-vinylpyridine as a functional monomer and ethylene dimethacrylate (EDMA) as a cross-linker and served to prepare an MIP packed column. BPA in an aqueous solution was adsorbed to an MIP packed column and eluted by acetonitrile/phosphate buffer (60/40, v/v). From aqueous solution, BPA was adsorbed to the column and eluted completely in the eluent. The eluted BPA was electrochemically detected by cyclic voltammetry. Optimum pH and scan rate were 7.0 and 0.1 V/s in phosphate buffer. Electrochemical detection of BPA in acetonitrile/phosphate buffer was performed, and linear relationship between BPA and anodic peak current was observed at the range of 10–100 μM. In the eluent, anodic peak current of BPA was observed around 650 mV.
Electrochemical Preparation of a Molecularly Imprinted Polypyrrole-modified Pencil Graphite Electrode for Determination of Ascorbic Acid  [PDF]
Levent ?zcan,Mutlu Sahin,Yücel Sahin
Sensors , 2008, DOI: 10.3390/s8095792
Abstract: A molecularly imprinted polymer (MIP) polypyrrole (PPy)-based film was fabricated for the determination of ascorbic acid. The film was prepared by incorporation of a template molecule (ascorbic acid) during the electropolymerization of pyrrole onto a pencil graphite electrode (PGE) in aqueous solution using a cyclic voltammetry method. The performance of the imprinted and non-imprinted (NIP) films was evaluated by differential pulse voltammetry (DPV). The effect of pH, monomer and template concentrations, electropolymerization cycles and interferents on the performance of the MIP electrode was investigated and optimized. The molecularly imprinted film exhibited a high selectivity and sensitivity toward ascorbic acid. The DPV peak current showed a linear dependence on the ascorbic acid concentration and a linear calibration curve was obtained in the range of 0.25 to 7.0 mM of ascorbic acid with a correlation coefficient of 0.9946. The detection limit (3σ) was determined as 7.4x10-5 M (S/N=3). The molecularly-imprinted polypyrrole-modified pencil graphite electrode showed a stable and reproducible response, without any influence of interferents commonly existing in pharmaceutical samples. The proposed method is simple and quick. The PPy electrodes have a low response time, good mechanical stability and are disposable simple to construct.
Molecularly Imprinted Nanomaterials for Sensor Applications  [PDF]
Muhammad Irshad,Naseer Iqbal,Adnan Mujahid,Adeel Afzal,Tajamal Hussain,Ahsan Sharif,Ejaz Ahmad,Muhammad Makshoof Athar
Nanomaterials , 2013, DOI: 10.3390/nano3040615
Abstract: Molecular imprinting is a well-established technology to mimic antibody-antigen interaction in a synthetic platform. Molecularly imprinted polymers and nanomaterials usually possess outstanding recognition capabilities. Imprinted nanostructured materials are characterized by their small sizes, large reactive surface area and, most importantly, with rapid and specific analysis of analytes due to the formation of template driven recognition cavities within the matrix. The excellent recognition and selectivity offered by this class of materials towards a target analyte have found applications in many areas, such as separation science, analysis of organic pollutants in water, environmental analysis of trace gases, chemical or biological sensors, biochemical assays, fabricating artificial receptors, nanotechnology, etc. We present here a concise overview and recent developments in nanostructured imprinted materials with respect to various sensor systems, e.g., electrochemical, optical and mass sensitive, etc. Finally, in light of recent studies, we conclude the article with future perspectives and foreseen applications of imprinted nanomaterials in chemical sensors.
Molecularly Imprinted Membranes  [PDF]
Francesco Trotta,Miriam Biasizzo,Fabrizio Caldera
Membranes , 2012, DOI: 10.3390/membranes2030440
Abstract: Although the roots of molecularly imprinted polymers lie in the beginning of 1930s in the past century, they have had an exponential growth only 40–50 years later by the works of Wulff and especially by Mosbach. More recently, it was also proved that molecular imprinted membranes ( i.e., polymer thin films) that show recognition properties at molecular level of the template molecule are used in their formation. Different procedures and potential application in separation processes and catalysis are reported. The influences of different parameters on the discrimination abilities are also discussed.
The Application of Molecularly Imprinted Polymers  [PDF]
Ming Zhao, Guijun Shen
Journal of Materials Science and Chemical Engineering (MSCE) , 2015, DOI: 10.4236/msce.2015.37010

Molecularly imprinted technology (MIT) has the characteristics of specificity and high selectivity, which is one of the most promising methodologies. Besides, the polymers are made using MIT as the functional material of solid-phase extraction and chromatographic fractionating and sensor, because of the characteristics of the high selectivity, the better stability and easy preparation. This review introduces the progress in the application of MIT and summarizes its application in the chemistry.

Synthesis and Theoretical Study of Molecularly Imprinted Nanospheres for Recognition of Tocopherols  [PDF]
Theeraphon Piacham,Chanin Nantasenamat,Thummaruk Suksrichavalit,Charoenchai Puttipanyalears,Tippawan Pissawong,Supanee Maneewas,Chartchalerm Isarankura-Na-Ayudhya,Virapong Prachayasittikul
Molecules , 2009, DOI: 10.3390/molecules14082985
Abstract: Molecular imprinting is a technology that facilitates the production of artificial receptors toward compounds of interest. The molecularly imprinted polymers act as artificial antibodies, artificial receptors, or artificial enzymes with the added benefit over their biological counterparts of being highly durable. In this study, we prepared molecularly imprinted polymers for the purpose of binding specifically to tocopherol (vitamin E) and its derivative, tocopherol acetate. Binding of the imprinted polymers to the template was found to be two times greater than that of the control, non-imprinted polymers, when using only 10 mg of polymers. Optimization of the rebinding solvent indicated that ethanol-water at a molar ratio of 6:4 (v/v) was the best solvent system as it enhanced the rebinding performance of the imprinted polymers toward both tocopherol and tocopherol acetate with a binding capacity of approximately 2 mg/g of polymer. Furthermore, imprinted nanospheres against tocopherol was successfully prepared by precipitation polymerization with ethanol-water at a molar ratio of 8:2 (v/v) as the optimal rebinding solvent. Computer simulation was also performed to provide mechanistic insights on the binding mode of template-monomer complexes. Such polymers show high potential for industrial and medical applications, particularly for selective separation of tocopherol and derivatives.
An Amperometric Sensor for Sunset Yellow FCF Detection Based on Molecularly Imprinted Polypyrrole  [PDF]
Jinfeng Xu, Yi Zhang, Hao Zhou, Mingwei Wang, Peidong Xu, Juankun Zhang
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.410B041
An electrochemical method for fast detecting the concentration of sunset yellow FCF in wine samples was developed in this study. The sensor based on imprinted films which fabricated by electropolymerization of pyrrole on a glassy carbon electrode in the presence of sunset yellow FCF as the template. Comparing to the polypyrrole non-imprinted modified (NIP) electrode, the polypyrrole molecularly imprinted polymer (MIP) electrode improved the electrochemical performance of the sensor significantly. The peak current at about 0.26 V was linear with the concentration of sunset yellow FCF from 0.4 to 2 μM and from 2 to 8 μM. It can be used for more than 10 times to maintain a stable response result. The sensor had the good selectivity on sunset yellow FCF, amaranth and tartrazine, which the selection factors were 1.00, 0.80 and 0.85respectively.
Molecularly Imprinted Polymers: Present and Future Prospective  [PDF]
Giuseppe Vasapollo,Roberta Del Sole,Lucia Mergola,Maria Rosaria Lazzoi,Anna Scardino,Sonia Scorrano,Giuseppe Mele
International Journal of Molecular Sciences , 2011, DOI: 10.3390/ijms12095908
Abstract: Molecular Imprinting Technology (MIT) is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. Molecularly Imprinted Polymers (MIPs), the polymeric matrices obtained using the imprinting technology, are robust molecular recognition elements able to mimic natural recognition entities, such as antibodies and biological receptors, useful to separate and analyze complicated samples such as biological fluids and environmental samples. The scope of this review is to provide a general overview on MIPs field discussing first general aspects in MIP preparation and then dealing with various application aspects. This review aims to outline the molecularly imprinted process and present a summary of principal application fields of molecularly imprinted polymers, focusing on chemical sensing, separation science, drug delivery and catalysis. Some significant aspects about preparation and application of the molecular imprinting polymers with examples taken from the recent literature will be discussed. Theoretical and experimental parameters for MIPs design in terms of the interaction between template and polymer functionalities will be considered and synthesis methods for the improvement of MIP recognition properties will also be presented.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.