On-line Ultrasound-Assisted Dispersive Micro-Solid-Phase Extraction Based on Amino Bimodal Mesoporous Silica Nanoparticles for the Preconcentration and Determination of Cadmium in Human Biological Samples.

摘要: On-line ultrasound-assisted dispersive micro-solid-phase extraction (USA-DμSPE) has been developed for preconcentration and separation of trace amounts Cd(II) ions in 0.5 mL human biological samples. In a syringe with nylon membrane, new synthetic bulky amino bimodal mesoporous silica nanoparticles (NH2-UVM7) were dispersed as nanoadsorbent 5 mL diluted serum sample (1:10), after ultrasonic shaking, the liquid phase was separated from solid phase. At optimized pH, chemical physical adsorption cadmium occurred, respectively, based on complexation amine groups UVM7 (Cd:NH2-UVM7) nanoparticles. The analyte then back-extracted sorbent nitric acid solution (0.2 M), its concentration determined by electrothermal atomic absorption spectrometry (ETAAS). Under conditions, linear range, limit detection (LOD), factor (PF) obtained 0.01-0.56 μg L(-1), 0.002 μg L(-1), 25, respectively. capacity NH2-UVM7 found to be 108.6 mg g(-1) cadmium. validation methodology performed standard reference material (HSRM).