T. Frentiu, S.D. Anghel, M. Nicola, E. Darvasi, A. Simon, E. Cordos, Figures of merit and fundamental processes in the analysis of Ca from liquid samples using an r.f. CCP torch with tubular and ring electrodes, Croatica Chemica Acta, 72/4 (1999) 763-7789

Title: Figures of merit and fundamental processes in the analysis of Ca from liquid samples using an r.f. CCP torch with tubular and ring electrodes

Abstract: A radiofrequency capacitively coupled Ar plasma, obtained with a molybdenum tubular electrode placed inside a quartz tube and one or two copper ring electrodes placed outside the tube, was used as spectral source for determination of atoms, ions and molecular radicals of calcium. A simultaneous spectrometer equipped with a photodiode array was used for detection of emission spectra. The atomization and ionization processes of Ca species were studied in the presence and absence of NaCl and H3PO4 matrix, with both single ring and two rings electrode torches. The limits of detection are 250 ng mL(-1) for Call 393 nm, 100 ng mL(-1) for CaI 423 nm, 230 and 100 ng mL(-1) for CaOH 555 nm and 622 nm. The recovery degree for certified plasma serum samples was 99.4 +/- 4.4% and the RSD was between 3.8-4.9%. For 5 blood samples the RSD of Ca content is 2.9-4.4%.

Keywords: atomic emission spectrometry; capacitively coupled plasma; Ca determination; blood analysis

Author: E. Cordos