Preparation of Nicotine-Imprinted Monolith by in-situ Surface Imprinting onto Internal Hole Surface of Macroporous Silica for Selective Enrichment and Separation of Nicotine in Environmental Water Sample

A novel surface imprinting technique combined with in-situ polymerization was developed to prepare nicotine-imprinted monolith (MIPM) in a stainless column by grafting molecularly imprinted polymers (MIPs) onto the internal hole surface of macroporous silica. Binding capacity of this MIPM was evaluated by frontal chromatographic technique and the MIPM solid phase extraction researched. Then, the applicability for this MIPM to selectively gather nicotine in environmental water sample was evaluated. Results indicated that the pH value of mobile phase greatly influenced binding capacity of the MIPM. When the mobile phase was at pH 5.0, adsorption capacity was the highest, with a value of 6.4 mg/L. Furthermore, when a pH 9.0 phosphate buffer was used as elution solvent during solid phase extraction, the target compound could be selectively desorbed from the MIPM, with a recovery of 99.6%. In addition, no great loss in recovery emerged when this MIP monolith was repeatedly used for solid phase extraction of nicotine in environmental water sample, revealing a good repeatability.