University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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NIST 1547

Classification: Reference Material -> NIST -> 1547 -> Peach leaves

Citations 2

"Determination Of Selenium In Biological Samples Using ICP-QMS"
Atom. Spectrosc. 2000 Volume 21, Issue 5 Pages 149-155
Boulyga, S.;Dombovari, J.;Becker, J.S.;Dietze, H.J.

Abstract: A method for the determination of selenium traces in plant tissue samples is described. Freeze-dried and homogenized biological samples mere decomposed with HNO3, HF and H2O2 by using closed-vessel microwave digestion under temperature and pressure control. NIST SRM 1577b Bovine Liver and NIST SRM 1547 Peach Leaves reference materials were investigated to optimize the analytical procedure. Selenium concentrations were measured with quadrupole-based inductively coupled plasma mass spectrometry (ICP-QMS) using external calibration and the isotope dilution method. A special solution introduction device combining pneumatic nebulization with hydride generation in the thin liquid film on the walls of the minicyclonic spray chamber was employed for sample introduction into the ICP-MS, which allowed the sensitivity for Se to be increased by up to one order of magnitude without increasing the memory effects. SRMs were doped with different amounts (0, 0.1, 0.2, 0.5 and 1.0 µg/g) of enriched Se-78 spike (98.58% of Se-78) before digestion to study the method performance and selenium losses during sample preparation. For a given matrix selenium losses were reproducible as follows: 9.9±1.6% for Bovine Liver SRM, 15.8±3.6% for Peach Leaves SRM and 20.0±4.5% for the real plant tissue samples. The detection limit for selenium calculated for solid plant tissue was 0.2 µg/g (3s -criteria, m/z=82, digestion 1:1000) using conventional pneumatic nebulization for solution introduction and 0.03 µg/g for a combination of pneumatic nebulization with hydride generation. Applying the method developed, a large number of plant tissue samples were analyzed to study selenium behavior and accumulation in the environment.
Selenium Mass spectrometry Reference material Volatile generation

"Development Of An Ultrasonic Nebulizer Using A Domestic Humidifier"
Bull. Korean Chem. Soc. 1999 Volume 20, Issue 11 Pages 1277-1280
Pyung Heum Yeon, Young Min Cho, and Yong-Nam Pak*

Abstract: An inexpensive ultrasonic nebulizer (USN) was developed utilizing a home humidifier. The ultrasonic transducer was taken from a commercial USN and the power supply was from a humidifier. Sample was continuously fed into the nebulizer and the detection limit was improved 3-20 times over a pneumatic nebulizer. Undesirably, noise in signal was also increased several times. 0.5 ppm of Mn was used as an internal reference and the 'long-term' drift could be successfully corrected. Since the noise contained high and low frequency components, both could be effectively removed only by the real-time correction method such as the Myer-Tracy method, where the reference line was simultaneously monitored with the analytical lines. The performance of USN was tested with NIST SRMs and showed good agreement with the certified values.
Cadmium Beryllium Bismuth Nickel Lead Zinc Tin Mass spectrometry Apparatus Nebulizer Optimization