Elemental Analysis of Phytotherapeutic Products by Inductively Coupled Plasma-Tandem Mass Spectrometry

Author(s)

Virgilio, Alex ; Amais, Renata Stabile ; Schiavo, Daniela ; Gomes Neto, Jose Anchieta ; Nobrega, Joaquim de Araujo

• Document type: Journal article
• Source: Analytical Letters; v. 50, n. 5, p. 842-852, 2017.
• Web of Science Citations: 1

Abstract

A procedure for the determination of As, Cd, Cr, Ni, Pb, and V in phytotherapy medicines by inductively coupled plasma-tandem mass spectrometry is reported. The use of tandem mass spectrometry with oxygen into an octopole reaction system at various gas flow rates and the combination of on-mass and mass-shift modes was evaluated. Cadmium, Cr, Ni, and Pb were determined as free atomic ions while As and V were determined as the oxides AsO+ and VO+ in the same run. Samples were prepared by microwave-assisted digestion with dilute nitric acid and hydrogen peroxide. Two plant-certified reference materials (apple leaves and tomato leaves) were used to check the accuracy. For tandem mass spectrometry with 0.5 mL min(-1) O-2, recoveries in the 85-113% were typically obtained and no statistical differences were observed at the 95% confidence level (t-test) in comparison with the certified values. Using these conditions, the limits of detection for the method were 0.01, 0.0002, 0.008, 0.008, 0.003, and 0.002 mu g g(-1) for As, Cd, Cr, Ni, Pb, and V, respectively. The procedure was used for the analysis of four phytotherapic drugs and the determined concentrations were up to 0.168 mu g g(-1) As, 0.03 mu g g(-1) Cd, 0.82 mu g g(-1) Cr, 1.18 mu g g(-1) Ni, 0.52 mu g g(-1) Pb, and 2.4 mu g g(-1) V with average precision values of 8% as the relative standard deviation. The found concentrations were compared with limits proposed in official guidelines and, in most cases, the values were below the maximum limits allowed. (AU)

• FAPESP's process: 13/26857-5 - Total concentrations and chemical speciation of As, Cr and Se using low pressure monolithic columns and inductively coupled plasma techniques
• Grantee: Renata Stábile Amais
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/18393-1 - Evaluation of gradient flow analysis as calibration strategy for spectroanalytical techniques with plasma source
• Grantee: Alex Virgilio
• Support Opportunities: Scholarships in Brazil - Post-Doctoral