A novel surface molecularly imprinted polymer as the solid-phase extraction adsorbent for the selective determination of ampicillin sodium in milk and blood samples

Surface molecularly imprinted polymers （SMIPs） for selective adsorption of ampicillin sodium were synthesized using surface molecular imprinting technique with silica gel as a support. The physical and morphological characteristics of the polymers were investigated by scanning electron microscope （SEM）, Fourier transform infrared spectroscopy （FT-IR）, thermogravimetric analysis （TGA）, elemental analysis and nitrogen adsorption-desorption test. The obtained results showed that the SMIPs displayed great adsorption capacity （13.5 lag/mg）, high recognition ability （the imprinted factor is 3.2） and good binding kinetics for ampicillin sodium. Finally, as solid phase extraction adsorbents, the SMIPs coupled with HPLC method were validated and applied for the enrichment, purification and determination of anapicillin sodium in real milk and blood samples. The averages of spiked accuracy ranged from 92.1% to 107.6%. The relative standard deviations of intra- and inter-day precisions were less than 4.6%. This study provides a new and promising method for enriching, extracting and determining ampicillin sodium in complex biological samples.

Molecularly Imprinted Polymers on Chloromethyl Polystyrene Resin Prepared via RAFT Polymerization

Surface molecularly imprinted polymers （SMIP） was prepared via the reversible addition-fragmentation chain transfer （RAFT） polymerization on the chloromethyl polystyrene resin （CPR） in the presence of the template D-phenylalanine. The structure of SMIP was characterized by FTIR and SEM. The adsorption behavior of D-phenylalanine of SMIP was preliminarily investigated.

Preliminary investigations into surface molecularly imprinted nanoparticles for Helicobacter pylori eradication

This paper reports investigations into the preparation and characterization of surface molecularly imprinted nanoparticles(SMINs) designed to adhere to Helicobacter pylori(H.pylori).Imprinted nanoparticles were prepared by the inverse microemulsion polymerization method.A fraction of Lpp20,an outer membrane protein of H.pylori known as NQA,was chosen as template and modified with myristic acid to facilitate its localization on the surface of the nanoparticles.The interaction between these SMINs with the template NQA were evaluated using surface plasmon resonance(SPR),change in zeta potential and fluorescence polarization(FP).The results were highly consistent in demonstrating a preferential recognition of the template NQA for SMINs compared with the control nanoparticles.In vitro experiments also indicate that such SMINs are able to adhere to H.pylori and may be useful for H.pylori eradication.

Detection of parathion methyl using a surface plasmon resonance sensor combined with molecularly imprinted films

An ultra-sensitive and highly selective parathion methyl （PM） detection method by surface plasmon resonance （SPR） combined with molecularly imprinted films （MIF） was developed. The PM-imprinted film was prepared by thermo initiated polymerization on the bare Au surface of an SPR sensor chip, Template PM molecules were quickly removed by an organic solution of acetonitrilelacetic acid （9：1, v/v）, causing a shift of 0.5° in SPR angle. In the concentrations range of 10^-13-10^-10 mol/L, the refractive index showed a gradual increase with higher concentrations of template PM and the changes of SPR angles were linear with the negative logarithm of PM concentrations. In the experiment, the minimum detectable concentration was 10^-13 mol/L. The selectivity of the thin PM-imprinted film against diuron, tetrachlorvinphose and fenitrothion was examined, but no observable binding was detected. The results in the experiment suggested that the MIF had the advantages of high sensitivity and selectivity.

Surface plasmon resonance sensor chips for the recognition of bovine serum albumin via electropolymerized molecularly imprinted polymers

In this paper, a surface plasmon resonance （SPR） sensor chip for detection of bovine serum album （BSA） was prepared by electropolymerization of 3-aminophenylboronic acid （3-APBA） based on molecularly imprinted polymer （MIP） technique. The surface morphology of MIP and non-imprinted （NIP） films were characterized by scanning electroscopy （SEM）. SEM images exhibited nanoscale cavities formed on the MIP films surface homogeneously due to the removal of BSA templates. The effects of pH, ion strength of rebinding BSA, the specific binding and selective recognition were studied for MIP films. Results indicated that the BSA-imprinted films exhibited a good adsorption of template protein （0.02-0.8 mg/mL） in 0.05 mol/L sodium phosphate buffer at pH 5.0 with the limit of detection （LOD） of 0.02 mg/mL.