Reference type: Journal
Authors: Lu Q, Chen XM, Nie L, Luo J, Jiang HJ, Chen LN, Hu Q, Du SH, Zhang ZP
Article Title: Tuning of the vinyl groups' spacing at surface of modified silica in preparation of high density imprinted layer-coated silica nanoparticles: A dispersive solid-phase extraction materials for chlorpyrifos.
Publication date: 2010
Journal: Talanta
Volume: 81
Issue: (3)
Page numbers: 959-966.
DOI: 10.1016/j.talanta.2010.01.044
Alternative URL: http://www.sciencedirect.com/science/article/B6THP-4Y7P8VB-2/2/a72096bfcde7a2fc3666f51e07bc1b3f

Abstract: This paper reports the preparation of high density imprinted layer-coated silica nanoparticles toward selective recognition and fast enrichment of chlorpyrifos (CP) from complicated matrices. The molecularly imprinted polymers (MIPs) were successfully coated at the surface of modified silica through using the chemical immovable vinyl groups at the nanoparticles' surface, followed by the graft copolymerization of methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) in the presence of templates CP. It has been demonstrated that the space of end vinyl groups at the surface of silica can be controlled by changing the condition of chemical modification, regulating the thickness of imprinted shells and the density of efficient imprinted sites. After removal of templates by solvent extraction, the recognition sites of CP were created in the polymer coating layer. The CP-imprinted nanoparticles exhibited high recognition selectivity and binding affinity to CP analyte. When the CP-imprinted nanoparticles were used as dispersive solid-phase extraction (dSPE) materials, the high recovery yields of 76.1-93.5% from various spiked samples with only 1áμg/mL analyte were achieved by one-step extraction. These results reported herein provide the possibility for the separation and enrichment of CP from complicated matrices by the molecular imprinting modification at the surface of common silica nanoparticles
Template and target information: chlorpyrifos, CP
Author keywords: molecular imprinting, Modified silica nanoparticles, Grafting to, Dispersive solid-phase extraction, Phosphate pesticides