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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Analytical Methods and Instrumentation

  • Publisher: Wiley
  • FAD Code: ANMI
  • CODEN: ANMIEB
  • ISSN: 1063-5246
  • Abbreviation: Anal. Methods Instrum.
  • DOI Prefix: NA
  • Language: English

Citations 4

"Comparison Of Flow Injection Methods For Nitrate Analysis In Aqueous Environmental Samples"
Anal. Methods Instrum. 1995 Volume 2, Issue 6 Pages 330-336
A.Cerdà, M.T.Oms, V.Cerdà, R.Forteza

Abstract: Reduction of nitrate to nitrite was carried out by means of a Cd-Cu column, by hydrazine, or by photochemical reduction. The chromogenic reagent was 0.5 g/l N-(1-naphthyl)ethylenediamine hydrochloride, 20 g/l sulfanilamide and 50 mL concentrated HCl. Nitrites were detected at 540 nm using a diode array detector. Liquids were pumped with Gilson peristaltic pumps and tubing was of PTFE (0.5 mm i.d.). The UV light source was a 15 W Hg lamp. With the Cd-Cu column, calibration was linear in the range 6-250 µM-nitrate and 2-250 µM-nitrite and detection limits were 0.5 µM-nitrate and 0.2 µM-nitrite. There was no interference from 200 ppm chromate, sulfate and carbonate, 100 ppm Ca(II), Fe(II), NI(II) and Cu(II) and 40 ppm Mg(II) and Zn(II). With hydrazine reduction, detection limits were 0.01 µM and 0.05 µM for nitrite and nitrate, respectively, with response linear up to 300 µM and 200 µM, respectively. With photochemical reduction, calibration graphs were linear in the range 1-300 µM-nitrate, and 1-400 µM (with UV radiation) and 1-200 µM (without UV radiation) for nitrite. The detection limit for nitrate was 0.12 µM.
Nitrate Environmental Spectrophotometry Reduction column Interferences Method comparison Photochemistry Chromogenic reagent

"FTIR Microscopy As Novel Detection System In Micro Flow Injection Analysis"
Anal. Methods Instrum. 1995 Volume 2, Issue 1 Pages 52-54
Kellner, Robert; Lendl, Bernhard

Abstract: A Bruker 113v FTIR spectrometer was coupled with a Bruker IR microscope equipped with a HgCdTe detector. A flow-through cell was developed for this system comprising three parts; the central part of which was constructed of PVC with an inner volume of 1.6 µL and an optical pathlength of 500 µm. The windows consisted of two Si plates (diameter 5.5 mm, thickness 0.75 mm). As the IR beam is focused by the FTIR microscope down to 80 µm it was possible to probe volumes of 10 nl. IBMK was determined in hexane in the ppm range as a model substance. Possible future applications of the system as a µtotal analysis system are discussed.
Methyl isobutyl ketone Organic compound Microscopy Apparatus MIBK

"Automated Optical Sensing System For Biochemical Assays: A Challenge For ELISA?"
Anal. Methods Instrum. 1993 Volume 1, Issue 1 Pages 43-51
Oroszlan, P.;Thommen, C.;Wehrli, M.;Duveneck, G.;Ehrat, M.

Abstract: The FOBIA (fiber-optic biospecific interaction analysis) system, based on FIA combined with evanescent-wave optical-fiber fluoroimmunosensor technology, is described, which can be used in both competitive and sandwich assays. The immunosensor can be regenerated 350 times, the cycle time is 15 to 30 min, and the the coefficient of variation of the signal is 1 to 5%. It is inferior to ELISA in parallel analyzes, but gives better results in a shorter time. Applications in both the clinical and environmental fields are described.
Environmental Fluorescence Immunoassay Clinical analysis Optical fiber

"Micro-systems For Flow Injection Analysis"
Anal. Methods Instrum. 1993 Volume 1, Issue 1 Pages 38-42
Van Der Schoot, B.H.;Jeanneret, S.;Van Den Berg, A.;De Rooij, N.F.

Abstract: A modular miniature FIA system composed of a glass body and micro-machined silicon parts for fluid handling and incorporating four ISFET for detection is described.
Field effect transistor Miniaturization