Electrochemically synthesized polymers in molecular imprinting for chemical sensing

This critical review describes a class of polymers prepared by electrochemical polymerization that employs the concept of molecular imprinting for chemical sensing. The principal focus is on both conducting and nonconducting polymers prepared by electropolymerization of electroactive functional monomers, such as pristine and derivatized pyrrole, aminophenylboronic acid, thiophene, porphyrin, aniline, phenylenediamine, phenol, and thiophenol. A critical evaluation of the literature on electrosynthesized molecularly imprinted polymers (MIPs) applied as recognition elements of chemical sensors is presented. The aim of this review is to highlight recent achievements in analytical applications of these MIPs, including present strategies of determination of different analytes as well as identification and solutions for problems encountered

Impact of culture media glucose levels on the intestinal uptake of organic cations

There are several data concerning transporters expression and/or regulation in cell lines maintained in different conditions, such as medium glucose concentration. This work aimed to evaluate the influence of two different extracellular glucose concentrations, commonly used in culture media, on the intestinal absorption of organic cations. Thus, the effect of 5.5 mM glucose and 25 mM glucose (HG) in culture media, was studied on [3H]-MPP+ (1-methyl-4-phenylpyridinium iodide) uptake in Caco-2 cells. Expression of human organic cation transporter type 1 (hOCT1) and human organic cation transporter type 3 (hOCT3) was investigated in cells cultured at both glucose concentrations. [3H]-MPP+ uptake, as well as its affinity for the transporter, were significantly decreased in HG cells. Moreover, hOCT3 mRNA levels were reduced in HG cells. Functional confirmation of this result was made using hOCT3 inhibitors. In conclusion, maintenance of Caco-2 cells (commonly used in several in vitro studies on membrane transport) in HG conditions affects organic cation transport at the intestinal level. Hence, results obtained in these conditions must be analysed with great care, since extracellular glucose levels may originate changes in organic cation nutrient and drug bioavailability