Preparation of Magnetic Molecularly Imprinted Polymer for Cyclobarbital and Its Application to the Assay of Phenobarbital in Human Serum

Abstract

A magnetic molecularly imprinted polymer (M-MIP) for cyclobarbital (CY) has been prepared by a multi-step swelling and polymerization method using a uniformly-sized magnetic particle as the shape template. Binding experiments and Scatchard analyses revealed that two classes of binding sites, high and low affinity sites, were formed on the M-MIP. The retention and molecular-recognition properties of the M-MIP toward CY, phenobarbital (PB), amobarbital (AM) and phenytoin (PT) were evaluated using a mixture of phosphoric acid and/or sodium phosphate buffer and acetonitrile as a mobile phase by LC. On the M-MIP, retention factors of CY, PB, AM and PT were drastically decreased at mobile phase pH 8.7. This could be ascribable to dissociation of these compounds, whose pKa values are around 8. The imprinting factors were in the order of CY > PB > AM > PT at mobile phase pHs 2.5-6.9, and those are very similar between CY and PB. Furthermore, they were decreased at mobile phase pH 8.7. In addition to shape recognition, hydrogen-bonding and hydrophobic interactions seem to work for the retention and molecular-recognition of CY, PB, AM and PT on the MIP. The M-MIP for CY was applied for the selective extraction of PB in human serum samples.

Preparation of Molecular Imprinted Polymer Based on Chitosan as the Selective Sorbent for Solid-Phase Microextraction of Phenobarbital

“…e proposed fiber shows high efficiency (due to the high selectivity of SPME-MIP fibers), as well as the convenience and low cost of fiber synthesis. On the other hand, the maximum adsorption amount using the SPME-MIP fiber used in this work for phenobarbital determination was 112.95 μg•g −1 , which was lower than the reported amounts in literature studies, such as Haginaka et al (812.82 μg•g −1 ) using the magnetic molecularly imprinted polymer (M-MIP) [27].…”

“…Another study employed a multistep swelling method to make uniformly sized magnetic MIP particles. The prepared MIP exhibited a high affinity and binding capacity for the extraction of PB from human serum samples [ 27 ]. Synthesis of new magnetic molecular imprinted materials [ 27 ], preparation of novel MIPs by sol-gel technology [ 5 , 28 ], and fabrication of brand-new coatings by green nanoparticles all belong to this concept [ 29 ].…”

“…The prepared MIP exhibited a high affinity and binding capacity for the extraction of PB from human serum samples [ 27 ]. Synthesis of new magnetic molecular imprinted materials [ 27 ], preparation of novel MIPs by sol-gel technology [ 5 , 28 ], and fabrication of brand-new coatings by green nanoparticles all belong to this concept [ 29 ]. In this study, we propose a novel, simple, and effective solid-phase microextraction technique for the determination of phenobarbital in water samples by HPLC-UV through covering of stainless-steel wires (supporting material) by homogenous chitosan biopolymer.…”

Development of Microfluidic Components for Micro Total Analysis Systems

“…Although the surface modification and a material of a microfluidic EOP should be improved for more sensitive sensing, the microfluidic pump worked as the adsorbate sensor. We expect that the combination of a molecular imprinting technology will reach to development of the new type of a molecular-selective sensor [42][43][44][45][46].…”