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
Website: @unf

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Classification: Fruit -> grape -> juice

Citations 3

"Flow Injection Analysis In Soil Research And Plant Analysis"
Fresenius J. Anal. Chem. 1988 Volume 329, Issue 6 Pages 701-706
K. Schaller, R. Lenhardt, V. Weber und C. Euler

Abstract: Flow diagrams and experimental conditions are given for the determination of N in soils, of NH3 in grape musts and juices, of P in soil extracts, of NO3- in plant extracts and of total amino-acid content, proline and arginine in plants. Each analysis is discussed and compared with other methods.
Nitrogen Phosphorus Nitrate Amino Acids Arginine l-Proline Sample preparation Method comparison Review Tecator

"Flow Injection Analysis With Electrochemical Detection"
Fresenius J. Anal. Chem. 1988 Volume 329, Issue 6 Pages 691-697
K. Cammann

Abstract: Two combinations of flow injection analysis with electrochemical detection are discussed. The use of potentiometry with ion-selective electrodes is illustrated by the determination of NO3- alone and simultaneously with Na+, K+, Ca(II), HCO3- and Cl- in drinking water, of Al without a reference electrode, of SO2 in grape juices, and of glucose in biological fluids. The apparatus is described and the experimental conditions are given. A hanging-mercury-drop electrode (at 0 V vs. Ag - AgCl) was used for the amperometric detection of ascorbic acid in a buffer (pH 4.7) stream.
Aluminum Ascorbic acid Glucose Nitrate Sulfur dioxide Amperometry Electrode Electrode Potentiometry Interferences Review

"Semiautomatic Determination Of Furanic Aldehydes In Food And Pharmaceutical Samples By A Stopped-flow Injection Analysis Method"
J. AOAC Int. 1993 Volume 76, Issue 6 Pages 1255-1261
Espinosa Mansilla, A.;Munoz De La Pena, A.;Salinas, F.

Abstract: Sample solution was injected into a carrier stream of water which merged sequentially with a stream of 5 M HCl and a stream of 0.03 M 2-thiobarbituric acid. The procedure was carried out at 40°C and the reaction was monitored at 425 nm. A schematic diagram of the stopped-flow FIA system is presented. The method was used to determine 5-hydroxymethyl-2-furfuraldehyde (I) and furfural in honey, orange and grape juice, red wine and pharmaceuticals. The calibration graph was linear for 1.1-14.6 µg/ml of I and the detection limit was 0.47 µg/ml. The RSD for 5.6 µg/ml of I (n = 10) was 2.4%. Sample throughput was ~40/h; details are given of the manual and automatic steps of the procedure. A kinetic study of the reactions of 5-hydroxymethyl-2-furfuraldehyde and furfural with 2-thiobarbituric acid (TBA) by a stopped-flow flow injection analysis technique has been undertaken. A semiautomatic method for the analytical determination of these furanic aldehydes is proposed on the basis of reaction with TBA. The proposed stopped-flow method was successfully applied to several commercial pharmaceutical preparations and food samples. The procedure is faster than the earlier procedure for determination of these compounds in foods and pharmaceuticals.
Aldehydes, furanic Spectrophotometry Stopped-flow Kinetic