Simultaneous Determination of Aluminium, Titanium and Vanadium in Serum by Electrothermal Vaporization–Inductively Coupled Plasma Mass Spectrometry

Abstract

The systemic distribution of corrosion and wear products from total joint replacement devices in the human body needs to be better understood. This requires the measurement of metal ions, especially Al, Ti and V, at ppb and sub-ppb levels in serum and other organic matrices. Both ETAAS and NAA have been reported for determining some of the elements, but neither is completely suitable for determining all three elements in serum at the levels encountered in control subjects and in patients with well-functioning devices. A method is described for the simultaneous determination of Al, Ti and V in serum using ETV–ICP-MS. Spectral interferences from the serum matrix were circumvented or alleviated by the careful selection of analytical masses, chemical modifiers and the temperature programme of the electrothermal vaporizer. The serum matrix was found to influence the transport of analytes (carrier effect) from the furnace to the plasma. The carrier effect was corrected by using major component matrix matching with internal standardization, and good recovery was obtained. Detection limits of 0.7, 0.4 and 0.1 ppb in serum were obtained for Al, Ti and V, respectively. NIST SRM 1598 Bovine Serum and a pooled human serum were analysed. The Al concentration found was 3.8±0.8 ppb while the V concentration was below the detection limit of 0.1 ppb, compared with the certified value for Al of 3.7±0.9 ppb and the information value for V of 0.06 ppb (no value is given for Ti in SRM 1598). The Ti value obtained for the pooled human serum sample was within the concentration range previously reported for normal human serum.