Evaluation of the protein concentration in enzymes via determination of sulfur by total reflection X-ray fluorescence spectrometry — limitations of the method

Direct analysis of biological samples by total reflection X-ray fluorescence

“…Although the chemical modifier concept is proper to GFAAS, it has been recently applied to TRXF [41]. Most of those works have involved thermal stabilization of volatile elements during the drying stage of the sample aliquot, but there are also some attempts made to improve the distribution and thickness of the solid residue left after sample drying on the reflector surface, prior to analysis by this technique [42,43].…”

Atomic spectrometry update. X-ray fluorescence spectrometry

“…The very low Ni and Sr concentrations in amniotic fluid did not show a dependence between the weight of the child and age of the mother, whereas a very weak correlation was found for Zn. Mertens et al 142 used the determination of S to evaluate the protein concentration in enzymes. As the isolation and cleaning procedures for enzyme samples were difficult and time consuming, only small amounts of sample were available, which made TXRF ideally suited to this analysis.…”

Development and Characterization of a Portable Total Reflection X-ray Fluorescence System Using a Waveguide for Trace Elements Analysis

“…2 According to Alov,3 diverse substances can be analyzed by TXRF; therefore, it makes sense to combine them into several groups: natural (water, soil, deposits, aerosols, and plants); [4][5][6] geological and mineralogical (ore, mineral raw materials, and crystals); [7][8][9] technological (petroleum and petroleum products, metals and melts, thin films, polymers, chemicals, and wastes); [10][11] and biomedical (blood, serum, urine, and human tissue). [12][13][14][15] Furthermore, wine, 16 archaeological, [17][18] art, 19 and forensic samples 20 can also be analyzed by TXRF. Synchrotron radiation or rotating anode X-ray sources have been used for the detection of low amounts of elements by TXRF.…”