Biomedical subjects

M Volkan

Publications and source records attributed to M Volkan.

3 recordsLinked to original sources

PubMed1998

Sample Preparation for Arsenic, Copper, Iron, and Lead Determination in Sugar.

Two sample preparation methods were modified and optimized for the determination of As, Cu, Fe, and Pb in white sugar using atomic absorption spectrometry (AAS). Analyses were carried out using hydride generation AAS (HG-AAS) for As and flame AAS (FAAS) for Cu, Fe, and Pb. White sugar samples were prepared by dry ashing of the samples with H(2)SO(4) and Mg(NO(3))(2). Recoveries for As, Cu, Fe, and Pb were 87.6, 92.8, 95.8, 91.1% respectively,in ashing with H(2)SO(4). They were 95.1, 92.4, 97.4, and 91.1%, respectively, in ashing with Mg(NO(3))(2).6H(2)O. When small quantities of spikes were used, 94.7 and 95.3% recoveries of arsenic were found for the procedures applying H(2)SO(4) and Mg(NO(3))(2), respectively.

Journal Article↗

PubMed1996

Determination of germanium by AAS in chloride-containing matrices.

Interference effects of NaCl on the ET-AAS determination of Ge have been studied. The use of several matrix modifiers to alleviate this problem such as Ni and Zn perchlorates and nitrates, nitric acid, ammonium nitrate are reported. The stabilizing effect of Zn and Ni perchlorates allows the use of high pretreatment temperatures. NaCl is thus thermally volatilized from the atomizer by employing pretreatment temperatures higher than 1500 degrees C resulting in an improved sensitivity. Germanium levels in zinc plant slag samples, have been determined and compared to those obtained for the same samples spiked with NaCl with platform and wall atomization using nickel perchlorate as a matrix modifier. The results were compared with those from a hydride generation system equipped with a liquid nitrogen trap. The recoveries for germanium have been almost complete and amount to 99% for the original slag samples and 80% for 15% (w/w) NaCl containing spiked samples.

Journal Article↗

PubMed1996

Hydrogen sulfide determination by solid surface luminescence.

In the analytical system suggested, atmospheric hydrogen sulfide reacts with the surface of a filter paper treated with aqueous cadmium chloride and yields a luminescent species whose intensity can be correlated with the analyte concentration in ambient air. It was shown that the luminescent species are CdS solid particles which were formed in a well defined size. The paper luminescence was also tried on polymeric surfaces; polyethyleneoxide, polyvinyl alcohol, ethylcellulose and carboxymethylcellulose were found to give a similar luminescence signal. The system can be used on the tip of an optical fiber for an irreversible, cumulative type of analytical device for hydrogen sulfide determination. The 3s detection limit for the paper luminescence detection system was 7.8 ppb H(2)S.

Journal Article↗