Abstract:

A novel reversed phase restrict access material was prepared via two steps of surface-initiated atom transfer radical polymerization (SI-ATRP). The stearyl methacrylate (C₁₈) and glycidylmethacrylate (GMA) were grafted on inner and outer surfaces of modified silica, allowing brominated silica and CuBr/2,2-pyridine to serve as macro-initiator and catalyst system. After hydrolysis, we got a hydrophilic reversed phase restrict access material with rich glycol group, which was characterized by Fourier transform infrared (FT-IR) spectrum, elementary analysis and thermogravimetric (TGA) analysis. The static adsorption experiment was employed for evaluating the binding capacity of the novel reversed phase restrict access material. The maximum adsorption amounts of sulfadimethoxine and oxytetracycline were 18.02 and 4.80 mg/g, respectively. The properties of material for the exclusion of proteins like bovine serum albumin (BSA) were evaluated using solid-phase extraction (SPE) and its exclusion value up to 90%. The novel reversed phase restrict access material was used for the separation and enrichment of oxytetracycline in milk. The high-performance liquid chromatography (HPLC) was used to detect the oxytetracycline and the average recovery was 89.19% with the relative standard deviation (RSD) of 3.03%. It is expected that the novel inversed restrict access material combined with HPLC or liquid chromatography-mass (LC-MS) analysis system is applied to the extraction and detection of biological samples.

Key words: bovine serum albumin (BSA), milk, oxytetracycline (OTC), restrict access material, sulfadimethoxine (SDM), surface-initiated atom transfer radical polymerization (SI-ATRP)