Search Our Scientific Publications & Authors

Spectrochim Acta Part B At Spectrosc 2016 Feb;116:21-27

Office of Regulatory Affairs, Arkansas Regional Laboratory, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079, United States.

This investigation reports a rapid and simple screening technique for the quantification of titanium and zinc in commercial sunscreens using portable X-ray fluorescence spectroscopy (pXRF). A highly evolved technique, inductively coupled plasma-mass spectroscopy (ICP-MS) was chosen as a comparative technique to pXRF, and a good correlation (r > 0.995) with acceptable variations (≤25%) in results between both techniques was observed. Read More

Spectrochim Acta Part B At Spectrosc 2014 Nov;101:123-129

Institute of Chemical Technologies and Analytics, Vienna University of Technology, Vienna, Austria.

Nebulising liquid samples and using the aerosol thus obtained for further analysis is the standard method in many current analytical techniques, also with inductively coupled plasma (ICP)-based devices. With such a set-up, quantification via external calibration is usually straightforward for samples with aqueous or close-to-aqueous matrix composition. However, there is a variety of more complex samples. Read More

Spectrochim Acta Part B At Spectrosc 2014 Sep;99(100):121-128

Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna, Austria.

The continuous downscaling of the process size for semiconductor devices pushes the junction depths and consequentially the implantation depths to the top few nanometers of the Si substrate. This motivates the need for sensitive methods capable of analyzing dopant distribution, total dose and possible impurities. X-ray techniques utilizing the external reflection of X-rays are very surface sensitive, hence providing a non-destructive tool for process analysis and control. Read More

Spectrochim Acta Part B At Spectrosc 2008 Jun;63(6):685-691

Institute of Analytical Chemistry of the ASCR, v.v.i., Vídeòská 1083, 14220 Prague, Czech Republic.

An improvement of current method of selective hydride generation based on pre-reduction for differentiation of tri- and pentavalent arsenicals is described, applied for the oxidation state specific speciation analysis of inorganic, mono-, di- and trimethylated arsenicals with minimum sample pretreatment using atomic absorption spectrometry with the multiatomizer. The preconcentration and separation of arsine, methylarsine, dimethylarsine and trimethylarsine is then carried out by means of cryotrapping. Presented study shows that 2% (m/v) L-cysteine hydrochloride monohydrate (L-cys) currently used for off-line pre-reduction of pentavalent arsenicals can be substituted with 1% (m/v) thioglycolic acid (TGA). Read More

Spectrochim Acta Part B At Spectrosc 2008 Mar;63(3):396-406

Institute of Analytical Chemistry of the ASCR, v.v.i., Vídeňská 1083, 14220 Prague, Czech Republic.

An automated system for hydride generation - cryotrapping- gas chromatography - atomic absorption spectrometry with the multiatomizer is described. Arsines are preconcentrated and separated in a Chromosorb filled U-tube. An automated cryotrapping unit, employing nitrogen gas formed upon heating in the detection phase for the displacement of the cooling liquid nitrogen, has been developed. Read More

Spectrochim Acta Part B At Spectrosc 2008 Feb;63(2):95-103

Fitzpatrick Institute for Photonics, Department of Biomedical Engineering and Department of Chemistry, Duke University, Durham, NC 27708, USA.

This article presents an overview of the development, operation, and applications of optical nanobiosensors for use in detection of biotargets in individual living cells. The nanobiosensors are equipped with immobilized bioreceptor probes (e.g. Read More