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

作者：Vanesa Taboada Lopez Maria; Iglesias Lopez Sara; Herbello Hermelo Paloma; Bermejo Barrera Pilar; Moreda Pineiro Antonio^*

来源：Analytica Chimica Acta, 2018, 1018: 16-25.

DOI：10.1016/j.aca.2018.02.075

• Titanium dioxide nanoparticles
• Bivalve mollusk
• Ultrasonic probe
• Enzymatic hydrolysis
• sp-ICP-MS

Applicability of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) using dwell times equal to or shorter than 100 mu s has been tested for assessing titanium dioxide nanoparticles (TiO2 NPs) in bivalve mollusks. TiO2 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 L-1 of pancreatin and lipase (pH 7.4). The developed method was found to be repeatable (repeatability of 17% for the over-all procedure, TiO2 NPs concentration of 5.33 x 10(7) +/- 8.89 x 10(6), n = 11), showing a limit of detection of 5.28 x 10(6) NPs g(-1), and a limit of detection in size of 24.4-30.4 nm, based on the 3 sigma criteria, and on the 3 sigma/5 sigma criteria, respectively. The analytical recovery within the 90-99% range (use of TiO2 NPs standards of 50 nm at 7 and 14 mu g L-1 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 TiO2 NPs by the proposed method. TiO2 NPs concentrations were within the 2.36 x 10(7)-1.25 x 10(8) NPs g(-1) range, and the most frequent sizes were from 50 to 70 nm.

• 出版日期2018-8-14