Direct determination of lead in whole human blood by total reflection X-ray fluorescence spectrometry

Determination of platinum levels in serum and urine samples from pediatric cancer patients by TXRF

“…However, the DLs found for Pb were comparable to values reported in the literature. 15 A similar comparison for Pt was not possible since no reported DLs for this element in serum or urine samples using TXRF were found. Table 2 shows the sensitivity values for the determination of platinum obtained using the cut-off set-up for urine, Table 2 serum and deionized water.…”

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

“…The self-absorption and scattering must be minimized by an adequate sample preparation [11][12][13][14][15][16][17][18][19][20][21][22], e.g., microtomes, slurries, dilution, etc. and drying procedure.…”

“…Direct analysis by itself, or combined with in situ preparation procedures, is a suitable alternative for the quantitative determination of trace elements by TXRF in clinical samples as serum [22], whole blood [19], human brain [17], amniotic fluid [23] and lyophilized tissues [24]. The latter brings about a series of advantages, namely, reduction of analysis time and sample handling, the use of scarce samples and minimization of contamination and analyte losses.…”

“…This condition is difficult to attain, especially in biological and organic samples, due to the matrixassociated problems such as the scattering and/or selfabsorption of the impinging radiation. To overcome the difficulties some procedures are discussed in the literature: microwave-assisted wet [10,11] and vapor phase digestion [12], ultrasonic acid extraction [13], microtome sections [14,15], slurries [16,17], simple dilution [18], plasma ashing [19], hydride generation [20] and microwaveassisted drying [21]. Some of these procedures are carried out directly onto the sample reflector surface, partially minimizing sample manipulation and the subsequent possibility of contamination [14,15,19].…”

"Utilização de duas variantes da fluorescência de raios X (EDXRF e TXRF) na determinação de chumbo em águas e sedimentos"

“…Apesar do tempo gasto nesta digestão, apresenta a vantagem de necessitar diminutas quantidades da amostra, da ordem de miligramas (Ayala et al, 1991), e de ser multielementar e simultânea. …”