Preparation of carboxymethyl-α-cyclodextrin polymer grafted onto nano TiO2 as a novel solid phase extraction sorbent based on a host-guest mechanism

Carboxymethyl-alpha-cyclodextrin polymer grafted onto nano TiO2 (CM-alpha-CD PG/nano TiO2) was fabricated and its feasibility for the determination of levodopa (L-DOPA) was investigated. The synthesized sorbent was characterized by Fourier transform infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The adsorption mechanism is based on the host-guest effect between L-DOPA and CM-alpha-CD PG grafted on nano TiO2. The selectivity is due to the size of L-DOPA and also the hydrophobic interaction of CM-alpha-CD polymer with this compound. The experimental conditions were optimized for the separation/determination of L-DOPA. Under the optimum conditions, the adsorption capacity of CM-alpha-CD PG/nano TiO2 for L-DOPA and the preconcentration factor were 63.8 mu g g(-1) and 20, respectively. The limit of detection (LOD), the relative standard deviation (RSD), and the linear range were 0.016 mu g mL(-1), 2.3%, and 0.05-1.3 mu g mL(-1), respectively.