Using restricted-access materials and column switching in high-performance liquid chromatography for direct analysis of biologically-active compounds in complex matrices

Making biosamples compatible with instrumental analysis

“…They can be divided in synthetic or natural based materials depending on their origin. Among the synthetic ones, molecularly imprinted polymers (MIPs) [10] and restricted access materials (RAMs) [11] can be highlighted. However, natural based materials comprising biomolecules are gaining special interest due to their enhanced selectivity (close to specificity) towards the target analytes [12].…”

Current Developments and Future Trends in Solid-phase Microextraction Techniques for Pharmaceutical and Biomedical Analyses

“…85,86 Molecularly imprinted polymers (MIPs) [87][88][89][90] are stable, selective and cross-linked synthetic polymers synthesized by the copolymerization of a monomer with a cross-linker in the presence of a template molecule, and used to coat SPME fibers, inner surfaces of capillaries and sorbent particles. Testosterone-imprinted SPME fiber was developed for the selective extraction of anabolic steroids in urine samples and their analysis by GC-MS. 91 The principle of restricted access materials (RAM), 92 in which commercially available 35-μm LiChrospher RP-18 alkyl-diol-silica and ion exchange diol silica RAM particles are glued to a cleaned stainless-steel wire, has been adopted for direct SPME extraction from blood. This RAM-based SPME approach was able to simultaneously separate proteins from a biological sample, while directly extracting the active components from a natural drug.…”

A Novel Chip Device Based on Wired Capillary Packed with High Performance Polymer-based Monolith for HPLC: Reproducibility in Preparation Processes to Obtain Long Columns

“…[1][2][3][4] Among the variety of HPLC separation media, monolithic separation media [5][6][7] have recently been one of the best solutions for high throughput HPLC analyses due to their rather high permeability. [8][9][10][11][12] In addition, long capillary columns can be prepared and favorably utilized to realize ultra-high performance using ordinary LC systems.…”