TiO 2 @SiO 2 flexible nanofiber membrane-based syringe membrane solid phase extraction for determination of beryllium in Chinese yellow rice wine samples by graphite furnace atomic absorption spectrometry

Beryllium is an extremely toxic element for human beings. Therefore, knowledge of Be content in food samples is important to evaluating its potential effect on human health. The present study aimed to develop an efficient method for the quantification of Be in Chinese yellow rice wines. Samples were diluted with ultrapure water, and then directly analyzed by syringe membrane solid phase extraction (SMSPE) combined with graphite furnace atomic absorption spectrometry. TiO 2 @SiO 2 flexible nanofiber membrane (TSFNFM) was used as the sorbent of SMSPE for enriching Be and eliminating matrices. Detection limit was 0.52 ng L -1 for Be with relative standard deviation of 6.4%. The linear range of calibration curve was in the range of 0.03-25 ng mL -1 with a correlation coefficient of 0.9946. An enrichment factor of 150 was obtained for Be. Two certified reference materials of tea leaves and rice were analyzed by this method, and the obtained results were in good agreement with certified values. The recoveries of spiking experiments were in the range of 90.0-110%. This method avoided the labor-intensive and time-consuming vortex/ultrasound and centrifugation/filtration steps, which may result in sample contamination and analysis errors.