BOOSTing limits of detection for chromium and other trace elements in whole blood Application Note · PlasmaQuant MS Q

Introduction

The blood circulatory system is a transport system which continuously supplies the body with the oxygen, vitamins, fatty acids and nutrients it needs. With iron being the most prominent example, many elements are dissolved in blood or embedded in proteins that are required for the proper functioning of the organism. The presence of too high or too low concentrations of these elements can be an indication of a deficiency or an intoxication potentially leading to severe diseases. For this reason, the metallic profile of biological samples such as blood, serum, plasma and urine is routinely analyzed. In recent years, inductively coupled plasma mass spectrometry (ICP-MS) has become the method of choice for analyzing these sample types because of its speed and low detection limits.

Whole blood is a complex sample matrix with solid and liquid components and a relatively high carbon content deriving from the proteins and lipids in the blood. In some cases it is sufficient to determine the elemental concentration in the serum. However, some elements are partially located in the non-soluble blood fraction, the hematocrit, making the analysis of whole blood necessary. Due to its solid and liquid components the sample preparation of whole blood samples is difficult, as solid components must not precipitate. For this reason different procedures for sample preparation have been developed.

Here, we present a robust method for obtaining a metallic profile of whole blood with concentrations ranging from ppt to ppm level using alkali dilution for easy and fast sample preparation. With the patented BOOST technology, elements such as As, Se, Cr and V, which are typically difficult to measure in whole blood with ICP-MS, can be analyzed correctly with method limits of detection in the ng/l range. The accurate quantification of all elements during a long-term measurement of 8 hours proved the applicability of the method for the routine analysis of whole blood.