Two clozapine (CLZ) imprinted polymers were prepared by bulk and precipitation methods. Methacrylic acid and ethylene glycol dimethacrylate (EDMA) were used as functional and crosslinker monomers, respectively. The mean diameter and particle size distribution of the imprinted (P-MIP) and nonimprinted (P-NIP) particles obtained in precipitation method were examined. A conventional batch-adsorption test was applied for characterization of CLZ-polymer interaction. Dissociation constant (K D ) and maximum binding sites (B max ) were calculated using Scatchard analysis. To evaluate the recognition properties of polymers, phenytoin (PTN) binding to each polymer was also studied and compared to CLZ. The imprinting factor (IF) and selectivity factor (a) were also determined for each polymer. Average diameter and polydispersity of P-MIP were 925 nm and 0.17, respectively. The data for P-NIP were 1.05 lm and 0.18. The K D , IF, and a values calculated for P-MIP were 0.45 lM, 3.26, and 17.43, respectively. The data for imprinted polymer, prepared by bulk polymerization (B-MIP), were 14.5 lM, 1.95, and 3.67. These results demonstrated that precipitation polymerization is a more convenient, more effective, and more reproducible method than bulk polymerization for the synthesis of uniformly sized micron and submicronimprinted polymer particles.
In this article, a magnetic molecularly imprinted polymer (MMIPs) based on Fe 3 O 4 @SiO 2 has been synthesized for simply extraction of clozapine (CLZ) from human serum. The MIPs were coated on the Fe 3 O 4 @SiO 2 -NH 2 surface by the copolymerization of methacrylic acid with ethylene glycol dimethacrylate; and clozapine as template molecule. The properties of obtained Fe 3 O 4 @SiO 2 -MIPs were characterized by fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, dynamic light scattering, energy dispersive X-ray analysis (EDX), vibration sample magnetometer and rebinding experiments. The Fe 3 O 4 @SiO 2 -MIPs showed a highly improved imprinting capacity, a fast adsorption equilibrium, and significant selectivity in molecularly imprinted solid-phase extraction of CLZ from human serum. In addition, MMIPs were regenerated and their adsorption capacity in the eighth use was about 6.67% loss in clozapine solution. Also, the intra and inter-day precision values were 2 less than 6 and 4%, respectively. These results suggest Fe 3 O 4 @SiO 2 -MIPs may be used for selective extraction and analysis of CLZ in human serum.
Perfluorooctanesulfonate (PFOS), an anthropogenic fluorosurfactant, is one of the most common global pollutants. PFOS is used in various consumer products to provide soil, oil, and water resistance to materials used in clothing, upholstery, and food packaging. PFOS is persistent, bioaccumulative, and toxic to mammalian species. In this study, the cellular mechanisms involved in PFOS hepatotoxicity were evaluated. For this purpose, we determined oxidative stress markers including cell lysis, ROS generation, lipid peroxidation, glutathione depletion, mitochondrial membrane potential decrease, lysosomal membrane leakiness, and cellular proteolysis. Our results demonstrated that PFOS liver cytotoxicity was associated with reactive oxygen species (ROS) formation and lipid peroxidation in isolated rat hepatocytes. Incubation of hepatocytes with PFOS caused rapid depletion of hepatocyte glutathione (GSH), an important marker of cellular oxidative stress. Most of the PFOS-induced GSH depletion could be attributed to the expulsion of glutathione disulfide (GSSG). PFOS hepatotoxicity was inhibited by antioxidants and ROS scavengers, mitochondrial permeability transition (MPT) pore sealing agents, and endocytosis inhibitors. Our results suggest that PFOS hepatotoxicity might be the result of oxidative stress-induced lysosomal membrane leakiness and cellular proteolysis in rat hepatocytes.
A molecularly imprinted polymer designed for the selective extraction of donepezil from serum samples was synthesized using a noncovalent molecular imprinting approach. The molecularly imprinted polymer was evaluated chromatographically and then its affinity for donepezil was confirmed by solid-phase extraction. The optimal conditions for solid-phase extraction were provided by cartridge conditioning using acidified water purified from a Milli-Q system, sample loading under basic aqueous conditions, clean-up using acetonitrile, and elution with methanol/tetrahydrofuran. Desirable molecular recognition properties of the molecularly imprinted polymer led to good donepezil recoveries (90-102%). The data indicated that the imprinted polymer has a perfect selectivity and affinity for donepezil and could be used for selective extraction and analysis of donepezil in human serum.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.