Non-hydrolytic Sol-gel Methodology to Prepare a Molecularly Imprinted, Organic-silica Hybrid-based Stir Bar for Recognition of Sulfonylurea Herbicides

Molecular imprinting science and technology: a survey of the literature for the years 2004-2011

Herein, we present a survey of the literature covering the development of molecular imprinting science and technology over the years 2004-2011. In total, 3779 references to the original papers, reviews, edited volumes and monographs from this period are included, along with recently identified uncited materials from prior to 2004, which were omitted in the first instalment of this series covering the years 1930-2003. In the presentation of the assembled references, a section presenting reviews and monographs covering the area is followed by sections describing fundamental aspects of molecular imprinting including the development of novel polymer formats. Thereafter, literature describing efforts to apply these polymeric materials to a range of application areas is presented. Current trends and areas of rapid development are discussed.

Effect of the sol-gel route on the textural characteristics of silica imprinted with Rhodamine B

A series of silica xerogels that support Rhodamine B as a template were synthesized using distinct sol-gel routes, namely, acid-catalyzed routes, a base-catalyzed route, acid-catalyzed with base-catalyzed (two steps) hydrolytic routes, and a FeCl3 -catalyzed nonhydrolytic route. The extraction methods (thermal, Soxhlet, water washing, and ultrasound) were also evaluated. The resulting xerogels were characterized through porosimetry using nitrogen adsorption/desorption. The samples were further analyzed through small-angle X-ray scattering, Fourier transform infrared spectroscopy, and SEM. The preparation route affected the materials' textural properties. Extraction was optimized using acid and two-step routes. The acid route from Rhodamine B to Rhodamine 6G generated the highest selectivity factor (2.5). The nonhydrolytic route produced the best imprinting factor. Competitive adsorption was also used, from which the approximate imprinting factor was 2. The cavity shape generated during the production of the imprinted silica dictates the adsorption behavior, not the magnitude of the surface area.