Electrochemical MIP-based sensors

The first report on an electrochemical MIP based sensor was published in 1993... 

During the last decade the number of application of MIP-based sensors has increased dramatically. The high selectivity and affinity of MIPs for target analytes make them ideal recognition elements in the development of sensors. Capacitive (Panasyuk etal., 2001), conductimetric (Piletsky et al., 1995), field effect (Lahav et al., 2004), amper-ometric (Kritz and Mosbach, 1995), and voltammetric (Pizzariello et al., 2001), electrochemical transduction systems have been used. Sensors based on conductimetric transduction have been developed by Piletsky et al. (1995) for the analysis of herbicides. A system using a TiC>2 sol-gel system, and with a linear range of 0.01-0.50 mg L-1 for atrazine, without interference of simazine, and chloroaromatic acids has been described by Lahav et al. (2004). 

The present section is devoted to MIP-aided electrochemical sensors. Here, versatility in using electroanalytical techniques for determination of the analytes and their advantage over other detection techniques have been emphasized. A range of recognition MIP materials has been described. Several review papers, related to the electrochemical sensing based on MIPs, have already been available [16, 22-24]. The present chapter focuses on recent achievements in this research area. 

Scheme 4 Flow charts of general analyte determination procedures developed for MIP-based electrochemical sensors (adapted from [24])...

As it has been shown, basically all chiral MIP-based electrochemical sensors were developed up till now for amino acids or monosaccharides. However, chiral pharmaceuticals present more complex structures compared to the already mentioned molecules thus, their efficient molecular imprint is considered to be more difficult. Moreover, in the case of amino acids, the asymmetric carbon is at the molecule s extremity carrying two functional groups (-NH2 and -COOH) strongly interacting with the used common functional monomers, thus easily leading to highly enantiospecific imprinted cavities. 

In order to really prove the versatility and real analytical potentials of MIP-based chiral electrochemical sensors, in the near future their performance also toward more complex chiral molecules ought to be demonstrated so they could overcome the laboratory scale barrier. 

MIP-based tramadol sensing devices include the highly selective MWCNTs carbon paste electrode modified with molecularly imprinted polymers with differential pulse voltammetric detection. The device had a linear response range of 10 to 10" M [350]. The other report was on an MIP-electrochemical sensor prepared by coating SiO, Fe O, as the core and the supporting material, with an MIP based on ethyleneglycol dimethacrylate as the crosslinker and functional monomers. The MIP-modified particles prepared this way were eventually incorporated into the modified carbon paste electrode, which was used for cyclicvoltammetry of the analyte within a linear range of 0.01-20 pmolL-i [366]. 

Other instances include a micro-flow sensor on a chip for the analysis of terbuta-line through chemiluminescence (LR 8.0-100 ng/mL and DL 4.0 ng/mL) [435] an MIP-based electrochemical sensor for the impedance spectroscopic and chronoam-perometric determination of theophyUine (LR 2.00 X 10" -3.45 X10" M and DL 1.00 X 10" M) [369] a capacitive sensor for cyclic voltammetry of thiopental (LR 3-20... 

Khadro, B., et al. Molecularly imprinted polymers (MIP) based electrochemical sensor for detection of urea and creatinine. Procedia Eng. 5,371-374 (2010)... 

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