Computer-assisted design and synthesis of a highly selective smart adsorbent for extraction of clonazepam from human serum.

A computational approach was applied to screen functional monomers and polymerization solvents for rational design of molecular imprinted polymers (MIPs) as smart adsorbents for solid-phase extraction of clonazepam (CLO) form human serum. The comparison of the computed binding energies of the complexes formed between the template and functional monomers was conducted. The primary computational results were corrected by taking into calculation both the basis set superposition error (BSSE) and the effect of the polymerization solvent using the counterpoise (CP) correction and the polarizable continuum model, respectively. Based on the theoretical calculations, trifluoromethyl acrylic acid (TFMAA) and acrylonitrile (ACN) were found as the best and the worst functional monomers, correspondingly. To test the accuracy of the computational results, three MIPs were synthesized by different functional monomers and their Langmuir-Freundlich (LF) isotherms were studied. The experimental results obtained confirmed the computational results and indicated that the MIP synthesized using TFMAA had the highest affinity for CLO in human serum despite the presence of a vast spectrum of ions.

Computational design and synthesis of molecular imprinted polymers for selective extraction of allopurinol from human plasma.

The present study was focused on the rational development of polymers for selective extraction of allopurinol (ALP) from human plasma. Therefore, a computational modeling approach was combined with the molecular imprinting technology to obtain the polymers. The computational approach was used in order to screen the functional monomers as well as the polymerization solvents for rational design of molecular imprinted polymers (MIPs). It was based on the comparison of the binding energy (ΔE) of the formed complexes between the template molecule and different functional monomers. In the design, the effect of the polymerization solvent was also included using the polarizable continuum model. The theoretical calculation results showed that among virtual solvents tested, acrylamide (AAM) gave the largest ΔE while acrylonitrile (ACN) gave the smallest ΔE in acetone. Therefore, the MIP prepared using AAM as functional monomer in acetone was desired. To examine the validity of this approach, three MIPs were synthesized with different functional monomers i.e. AAM, acrylic acid (AA), and ACN, and then evaluated using Langmuir-Freundlich (LF) isotherm. The results obtained from this experiment confirmed the computational results that the MIP prepared by AAM was the most appropriate adsorbent. Subsequently, the MIP was used to develop a molecular imprinted solid-phase extraction (MISPE) procedure. Finally, the MISPE procedure followed by HPLC was developed for selective extraction and determination of allopurinol in human plasma. For the proposed MISPE method, the linearity between peak area and concentration was found in the range of 0.100-25.000 µM with a linear regression coefficient (R²) of 0.995. The limit of detection (LOD) and quantification (LOQ) in plasma were 0.028 and 0.093 µM, respectively. The results of this study indicated the possibility of using computer aided design for rational selection of functional monomers and solvents for preparation of the MIPs capable of extracting allopurinol from human plasma.