Determination of Lead in Botanicals/Chinese Prepared Medicines by Using Microwave Digestion with Flow Injection–Inductively Coupled Plasma–Mass Spectrometry

Abstract

A simple, sensitive, and rapid method was developed for the determination of lead in botanicals and Chinese prepared medicines (CPM) by using closed-vessel microwave digestion with flow injection–inductively coupled plasma–mass spectrometry. The limits of detection and quantitation for the method, based on 0.5 g digested sample, were calculated to be 0.10 and 0.61 mg/kg, respectively. A simple approach was proposed for calibration by multiple linear regression (MLR) with 207Pb, 206Pb, and 204Pb for the determination of lead in botanical and CPM samples. The results from calibration by MLR were compared with those obtained by conventional modes using 207Pb and the sum of 207Pb and 206Pb. The results obtained by the different modes of calibration were in good agreement for botanical and CPM samples. The method was found to have good accuracy for the analysis of botanical reference materials. Method precision based on analyses of different types of CPM samples by different analysts on different days for different levels of lead was between 3.0 and 8.0% (relative standard deviation, n = 6). The effect of possible matrix interference caused by nitric acid and the extent of digestion was investigated with the method of standard additions. Significant matrix interference was not observed for the CPM samples analyzed. MLR was used to examine the effect of variation in isotopic abundance, which was found to present no significant problem in the determination of lead in the botanical and CPM samples.

Quantitative Determination of Multiple Elements in Botanicals and Dietary Supplements Using ICP-MS

“…Traditional medicines based on herbal products and extracts play an ever-increasing role around the world , , and there is a rapidly growing trend in the consumption of herbal remedies in industrialized and developing countries. The botanicals used in the dietary supplements utilize different parts of the plant, including whole plants, roots, rhizomes, fruits, seeds, flowers, leaves, bark, and stem , , and contain a wide range of inorganic elements. Among them, heavy metals and metalloids, especially As, Cd, Hg, and Pb, are of primary concern due to their bioavailability and toxicity.…”

“…Previous studies have indicated that relatively high concentrations of these elements may occur in dietary supplements − . Other elements such as Mg, Mn, Ni, Cu, Zn, and Se are also present and found to have nutritional , as well as toxic effects for human health .…”

Analysis of Dietary Supplements for Arsenic, Cadmium, Mercury, and Lead Using Inductively Coupled Plasma Mass Spectrometry

“…ICP-MS has clear advantages in its multielement characteristics, speed of analysis, and detection limits. Quadrupole ICP-MS has been used to analyze various dietary supplements for the elements of interest ( − ). The higher mass resolution of an HR ICP-MS provides separation of analyte signals from known spectral interferences.…”

Multielemental Composition of Suet Oil Based on Quantification by Ultrawave/ICP-MS Coupled with Chemometric Analysis

“…These elements may be introduced into the food chain in various ways, including contamination during cultivation, processing, and storage. Other elements such as Mg, Ca, Mn, Ni, Cu, Zn, and Fe are also present and found to have both nutritional and toxic effects for human health [1,2,3].…”