Development of a method for the determination of titanium in tissue by graphite furnace atomic absorption spectrometry for clinical analysis

Abstract

A method was developed for the determination of low titanium concentrations in soft tissue. It is based on the microwave-assisted acid digestion of the samples and quantification of the element by graphite furnace atomic absorption spectrometry (GFAAS). The heating program was optimized through pyrolysis and atomization curves. The optimal temperatures were 1300 °C and 2600 °C for pyrolysis and atomization, respectively. Three matrix modifiers in various combinations were investigated and a mixture of 20 μg NH₄H₂PO₄ and 6 μg Mg(NO₃)₂ allowed the best sensitivity and signal profile to be obtained. Under optimum conditions, the detection and quantification limits were 0.82 μg L⁻¹ (33.61 ng g⁻¹ of tissue) and 2.50 μg L⁻¹ (102.48 ng g⁻¹ of tissue), respectively. The characteristic mass was 88 pg. The recovery of added titanium in tissue samples was from 77% to 117%. Titanium was detected in 9 clinical samples and 12 animal meat samples, and its content ranged from 0.11 to 0.80 μg g⁻¹.