Study Of Molecularly Imprinted Polymers Modified Electrodes And Their Analytical Application

In this dissertation the preparations of MIP film and carbon nanotubes/MIP composites (MWCNT@MIP) through electropolymerizing and surface imprinted technology are investigated, respectively. Moreover, MIP sensors are successfully constructed using MIP modified electrodes, and their analytical applications are also testified. The main contents are listed as follows:1. Benzophenone is one of the most commonly used photoinitiators of UV-cured inks on the food packaging materials and can migrate into the foodstuffs. In this study, an amperometric benzophenone sensor based on molecularly imprinted polymer (MIP) was successfully constructed for the first time. The sensor was prepared by electropolymerizing o-phenylenediamine (o-PD) on a glassy carbon electrode (GCE) in the presence of template benzophenone, and then removing template by immersing poly-o-phenylenediamine film-modified GCE in ethanol. The molecularly imprinted sensor was tested in the presence or absence of benzophenone by cyclic voltammetry and linear sweep voltammetry to verify the changes in the redox peak currents of potassium ferricyanide. The sensor responded sensitively to benzophenone over a linear range of0.05to5μM with a detection limit of10nM. The imprinted sensor showed high recognition ability for benzophenone and was successfully applied to the determination of benzophenone in food packaging material samples.2. A monolithic molecular imprinting sensor based on ceramic carbon electrode (CCE) has been reported. The sensor can be renewed simply by smoothing. It was fabricated by thoroughly mixing multiwalled carbon nanotube@molecularly imprinted polymer (MWCNT@MIP). graphite powder, and silicon alkoxide. and then packing the resulting complex mixture of components firmly into the electrode cavity of a Teflon sleeve. The incorporated MWCNT@MIP in CCEs functioned as recognition element for cholesterol determination. The MWCNT@MIP-CCEs were tested in the presence or absence of cholesterol by cyclic voltammetry and linear sweep voltammetry. The cholesterol sensor has excellent sensitivity with a linear range of10to300nM and a detection limit of1nM (S/N=3). The monolithic molecular imprinting sensor exhibits good stability, high sensitivity, and user-friendly reusability for cholesterol determination. This study shows that CCE is a promising matrix for MIP sensors.