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 -> cereal -> breakfast

Citations 4

"Chemiluminescence Flow Injection Analysis Determination Of Sucrose Using Enzymatic Conversion And A Microporous Membrane Flow Cell"
Anal. Chem. 1986 Volume 58, Issue 1 Pages 116-119
Cathy A. Koerner and Timothy A. Nieman

Abstract: Sucrose is initially converted into glucose by β-fructofuranosidase and aldose-1-epimerase (immobilized on controlled-porosity glass) in 0.1 M phthalate buffer (pH 5.65). The solution is then mixed with a stream containing luminol, haemin and horse-radish peroxidase in 0.1 M Tris (pH 10.5) and passes finally into a flow cell where it mixes with glucose oxidase in 0.1 M acetate buffer (pH 5). The H2O2 formed reacts with the luminol to produce chemiluminescence. The working range is 5 µM to 1 mM and analysis time is 2 min. For detection of sucrose in food products, a separate determination of glucose or a catalytic destruction of glucose in the sample is necessary to distinguish glucose originally present from that formed from sucrose.
Sucrose Glucose Chemiluminescence Immobilized enzyme Microporous membrane Flowcell

"Detection Of Zearalenone In Cereal Extracts Using High Performance Liquid Chromatography With Post-column Derivatization"
J. Chromatogr. A 1991 Volume 588, Issue 1-2 Pages 47-52
Michael T. Hetmanski* and Keith A. Scudamore

Abstract: Sample extracts were prepared according to previous techniques (c.f., J. Assoc. Off. Anal. Chem., 1979, 62, 1265 and Food Addit. Contam., 1989, 6, 35) and analyzed by HPLC on a column (25 cm x 4.6 mm) of Spherisorb ODS-1 (5 µm) with a mobile phase (1 mL min-1) of aqueous 80% methanol. The eluate was derivatized in a PTFE coil with 0.25 M aluminum chloride solution at ~50°C and zearalenone and zearalenol were detected fluorimetrically at 440 nm (excitation at 285 nm). The described methods led to a 5-fold increase in the fluorescence response of the cited mycotoxins without significantly affecting the level of background interference from co-extractives from cereal and animal feed samples.
Zearalenone HPLC Fluorescence Column Interferences Post-column derivatization

"Simultaneous Determination Of Pyridoxine, Riboflavine And Thiamine In Fortified Cereal Products By High Performance Liquid Chromatography"
J. Agric. Food Chem. 1984 Volume 32, Issue 6 Pages 1326-1331
Randy L. Wehling and David L. Wetzel

Abstract: Samples were extracted with 0.1N-H2SO4 and the extracts were incubated with Clarase fungal amylase preparation in aqueous Na acetate at 55°C for 1 h. After centrifugation, the supernatant solution was filtered and analyzed by HPLC on a column (25 cm x 4.6 mm) of µBondapak C18 with a mobile phase (1 mL min-1) of methanol - water - acetic acid (30:69:1) containing 5 mM Na hexanesulfonate. Pyridoxine(I) and riboflavine(II) were determined by fluorimetric detection at 418 nm (excitation at 288 nm). Thiamine(III) was determined by post-column derivatization with alkaline Fe(CN)63- solution and detection at 460 nm (excitation at 360 nm). The limit of detection was 2 µg g-1 for I and <1 µg g-1 for II and III. The coefficient of variation obtained were 1.66, 1.51 and 2.06% for I, II and III, respectively. Good correlation (r = 0.998) was obtained with a wet-chemical fluorescence procedure, but the HPLC method was more accurate for samples containing sucrose.
Pyridoxine Riboflavine Thiamine HPLC Fluorescence Post-column derivatization

"Flow Injection Analysis Of Phytic Acid By A Modified Molybdenum Blue Method"
Phytochem. Anal. 1998 Volume 9, Issue 3 Pages 119-123
Minori Kamaya*, Tomohiro Furuki, Kunio Nagagshima

Abstract: A simple and rapid flow injection analysis (FIA) of phytic acid in cereal food samples is reported based on a modified molybdenum blue method. The interference from inorganic phosphate ion was eliminated by using an anion exchange resin. The samples treated with the ion exchangers were analyzed using an FIA system at a sampling rate of 60 samples per h, and the determination showed a working range from 0.05 to 2.0 x 10^-3 M of phytic acid. The method was highly reproducible for measuring phytate in food material and proved to be more rapid than conventional methods.
Phytic acid Ion exchange Spectrophotometry Interferences Method comparison