Ultrasound assisted enzymatic hydrolysis for isolating titanium dioxide nanoparticles from bivalve mollusk before sp-ICP-MS.

Applicability of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) using dwell times equal to or shorter than 100??s has been tested for assessing titanium dioxide nanoparticles (TiO NPs) in bivalve mollusks. TiO NPs isolation from fresh mollusk tissues was achieved by ultrasound assisted enzymatic hydrolysis procedure using a pancreatin/lipase mixture. Optimum extraction conditions imply ultrasonication (60% amplitude) for 10?min, and 7.5?mL of a solution containing 3.0?g Lof pancreatin and lipase (pH 7.4). The developed method was found to be repeatable (repeatability of 17% for the over-all procedure, TiO NPs concentration of 5.33?×?10?±?8.89?×?10, n?=?11), showing a limit of detection of 5.28?×?10 NPs g, and a limit of detection in size of 24.4-30.4?nm, based on the 3? criteria, and on the 3?/5 ? criteria, respectively. The analytical recovery within the 90-99% range (use of TiO NPs standards of 50?nm?at 7 and 14??g?L as Ti). Several bivalve mollusks (clams, cockles, mussels, razor clams, oysters and variegated scallops) were analyzed for total titanium (ICP-MS after microwave assisted acid digestion), and for TiO NPs by the proposed method. TiO NPs concentrations were within the 2.36?×?10-1.25?×?10 NPs g range, and the most frequent sizes were from 50 to 70?nm.