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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Milk Whole

Classification: Agricultural -> dairy -> milk -> whole

Citations 3

"Ion-selective Field Effect Transistor (ISFET)-based Calcium Ion Sensor With Photocured Polyurethane Membrane Suitable For Ionised Calcium Determination In Milk"
Anal. Chim. Acta 2000 Volume 408, Issue 1-2 Pages 57-64
Andrey Bratov, NataliaAbramova, Carlos Domínguez and Antonio Baldi

Abstract: Ca2+-ion-sensitive ISFETs with photocured polyurethane-based polymer membranes with alkylphosphate exchanger (DOPPCa) and three neutral carrier ionophores (ETH 1001, ETH 129 and ETH 5234) and dioctylsebacate as plasticizer have been studied in pure CaCl2 solutions and in background solutions containing Na+, K+, Mg2+ ions in concentrations normally found in milk. In case of DOPPCa and ETH 1001 the influence of Mg2+ ions on the slope of the response curve is reported. ISFETs with membranes containing ETH 129 are shown to have high selectivity, more than 6 weeks life-time in constant contact with a solution and high precision of ionised calcium determination. Experimental results on determination of calcium ions in a whole milk are presented.
Calcium Field effect transistor Potentiometry Detector Interferences

"Dual-wavelength Photometry With Light Emitting Diodes. Compensation Of Refractive Index And Turbidity Effects In Flow Injection Analysis"
Anal. Chim. Acta 1994 Volume 289, Issue 3 Pages 347-353
Hanghui Liu and Purnendu K. Dasgupta*

Abstract: A mathematical method to compensate for both refractive index and turbidity effects in a dual-wavelength, double beam, dual-flow-cell photometric detection system is described (equations given). The method was demonstrated by determining µM concentrations (8-144 µM) of bromthymol blue in samples containing up to 1.5% whole milk and 60% ethanol with detection at 605 nm. The maximum absolute error was 3.75.
Bromothymol blue Spectrophotometry Dual detection Refractive index Turbidity

"Determination Of Neomycin In Milk By Reversed-phase Ion-pairing Liquid Chromatography"
J. Liq. Chromatogr. Relat. Technol. 1989 Volume 12, Issue 8 Pages 1497-1515
Badar Shaikh; Jean Jackson

Abstract: Milk was skimmed and a 1 mL portion was vortex-mixed with 20% trichloroacetic acid solution (100 µL) and centrifuged at 4000 rpm and 4°C for 30 min. A 180 µL portion of the supernatant liquid was vortex-mixed with 20 µL of 1 M Na pentanesulfonate - 0.07 M acetic acid, and a 25 µL aliquot of the mixture was analyzed by HPLC on a column (15 cm x 4.6 mm) fitted with a guard column (2 cm x 4.6 mm) both containing Supelcosil LC-8-DB (5 µm) at 32.5°C. Post-column derivatization was at 33°C in a reaction coil with phthalaldehyde. The ion-pairing mobile phase contained 0.01 M pentanesulfonate, 0.056 M Na2SO4, 7 mM acetic acid and 1.5% methanol and fluorimetric detection was at 455 nm (excitation at 340 nm). A calibration graph (peak heights) was rectilinear from 0.15 to 12 µg mL-1 of neomycin in whole milk, and overall recovery was 94%, with coefficient of variation of 6.8%. The method was applied to monitor neomycin in milk after intramuscular injection at 10 mg kg-1.
Neomycin B HPLC Fluorescence Column Post-column derivatization Detection limit Calibration Peak analysis