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: Food -> biscuit

Citations 3

"Electrocatalytic And Flow Injection Determination Of The Antioxidant T-butylhydroxyanisole At A Nickel Phthalocyanine Polymer Modified Electrode"
Anal. Chim. Acta 1995 Volume 305, Issue 1-3 Pages 49-56
M. A. Ruiz, M. G. Blázquez and J. M. Pingarrón*

Abstract: A nickel phthalocyanine polymer film was deposited on a glassy carbon disc electrode (3 mm diameter) from a solution containing 2 mM Ni(II)-4,9,16,23-tetraaminophthalocyanine monomer and 0.5 M tetraethylammonium perchlorate in DMSO by cycling the potential between -0.2 and +0.9 V vs. SCE at 200 mV/s for the desired number of cycles. The prepared electrode was used at +0.7 V in a FIA system with Ag/AgCl/3 M KCl reference and Au counter electrodes for the determination of the antioxidant t-butylhydroxyanisole (BHA). A carrier solution (3.3 ml/min) containing 0.1 M perchloric acid and 2% methanol was used and the injection volume was 200 µL. The calibration graph was linear for 0.01-10 mg/l BHA, the detection limit was 2.7 µg/l and the RSD (n = 10) for 0.5 mg/l BHA was 1.8%. The electrode responded to sodium bisulfite, t-butylhydroxytoluene, t-butylhydroquinone, ascorbic acid and propyl gallate (PG) and relative errors of higher than 10% were obtained for interferent:BHA concentration ratios of 2:1, 1:2, 1:10, 1:4 and 1:5 respectively. The method was applied to the determination of BHA in biscuits using a standard additions calibration procedure.
3-tert-butyl-4-hydroxyanisole Amperometry Electrode Electrode Interferences Standard additions calibration

"Development Of An Amperometric Enzyme Biosensor For The Determination Of The Antioxidant T-butylhydroxyanisole In A Medium Of Reversed Micelles"
Electroanalysis 1996 Volume 8, Issue 6 Pages 529-533
M. Asuncion Ruiz, A. Julio Reviejo, Concepcion Parrado, Jose M. Pingarrón

Abstract: A portion (5 g) of ground biscuit was extracted by shaking with 3 x 25 mL portions of ethyl acetate. After centrifugation, the combined extracts were concentrated to a small volume and diluted to 50 mL with a reversed micellar system consisting of ethyl acetate/0.1 M dioctyl sulfosuccinate/50 mM phosphate buffer of pH 7.4. A portion (150 µL) was injected into a flow injection system in which the carrier stream of the same micellar system. Amperometric measurements were made with a BAS VC-2 tyrosinase electrode, a Ag/AgCl electrode and a Pt wire electrode as the working, reference and counter electrodes, respectively. Calibration graphs were linear up to 1 mM t-butylhydroxyanisole with a detection limit of 30 µM. Batch experiments were also carried out in which the detection limit was 0.1 mM and the linear range was 0.2-2 mM. Of the common antioxidants usually used in food products, only propyl gallate interfered.
2-tert-Butyl-3-methoxyphenol Amperometry Sensor Electrode Electrode Micelle Interferences

"The Method Of Flow Injection Analysis And The Use Of Immobilized Glucose Oxidase: Glucose Determination In Food Products"
Potravin. Vedy 1991 Volume 9, Issue 2 Pages 81-88
Solich, P.;Karlicek, R.;Polasek, M.;Valentova, O.; Marek, M.

Abstract: Glucose was determined in foods by flow injection analysis (FIA) combined with the use of immobilized glucose oxidase. H2O2, a product of glucose oxidase, was detected on the basis of its Mo-catalyzed reaction with I-. The I2 produced forms a blue complex with starch and is determined at 585 nm. The calibration graph is linear in the range 0.25-0.8 mM glucose, with a relative standard deviation of 1.53 for 8 measurements at a glucose concentration. of 0.51 mM. The FIA method was used to determine glucose in candies and cookies. Accuracy, sensitivity, and speed are advantages of the proposed method. (SFS)
Glucose Spectrophotometry Immobilized enzyme