Rapid Determination of Multiple Inorganic Elements in Whole blood by Total Reflection X-Ray Fluorescence Spectrometry

The method mentioned by the title was proposed to achieve rapid and accurate determination of inorganic elements in whole blood samples. An aliquot (100 mg) of the whole blood sample treated by ethylenediaminetetraacetic acid (EDTA) anticoagulation was taken, and 10 mg of 100 mg · L⁻¹ gallium internal standard solution and 1% (mass fraction) Triton X-100 solution (diluent) of 100 mg, 500 mg or 1 000 mg (corresponding diluent to sample mass ratios of 1∶1, 5∶1, 10∶1, referred to as “dilution ratio”) were added for dispersion. After mixing and shaking for 2 min, the resulting solution was detected by total reflection X-ray fluorescence spectrometer. The content of inorganic elements in the whole blood sample was calculated using the relative sensitivity factor calculation formula conmined with internal method. It was shown that increasing the dilution ratio was beneficial for the dispersion of phosphorus, sulfur, potassium and calcium elements, which helped to improve the accuracy of their determination results. The use of relative sensitivity factor correction could increase the recovery of phosphorus and sulfur elements to over 80.0%. The proposed method was used for analyzing guinea pig sample, and inorganic elements of phosphorus, sulfur, potassium, calcium, iron, copper, zinc, rubidium and selenium were detected. Compared with inductively coupled plasma atomic emission spectrometry, absolute values of the relative errors of the determined values for the 9 inorganic elements were less than 10%, and RSDs (n=20) of the determined values were not greater than 18%. The detection limits (3s) of 7 elements (except rubidium and selenium) was 0.2-19 mg · L⁻¹. The method did not require sample digestion or standard curve production, and could complete the whole blood sample analysis within 25 min.