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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Corn Meal

Classification: Agricultural -> grain -> corn -> meal

Citations 2

"Amino-acid Analysis Of Feedstuff Hydrolysates By Cation-exchange High Performance Liquid Chromatography"
J. AOAC Int. 1985 Volume 68, Issue 5 Pages 1028-1032
Elkin RG, Griffith JE

Abstract: Corn, peanut and soya-bean meals were either untreated or oxidized with performic acid before hydrolysis with 6 M HCl containing phenol and L-aminohexanoic acid. The amino-acids were determined by HPLC on a column (25 cm x 3 mm) of cation-exchange material (Na+ form; 10 µm) with post-column derivatization with ninhydrin, and by conventional cation-exchange liquid chromatography by using a Beckman Model 119CL amino-acid analyzer.. The HPLC data were more precise than those of the second method (respective mean coefficient of variation of 0.22 and 0.67%) for amino-acid retention times, but more variable (respective mean coefficient of variation of 2.39 and 0.89%) for peak areas. Although some significant differences between the methods were noted, the amino-acid values found by both methods in general agreed very well. However, for each feed sample analyzed, the HPLC method gave consistently lower phenylalanine and tyrosine values. The results suggest that modular HPLC instrumentation can be used for the accurate and precise analysis of amino-acids in feed hydrolysates. The advantages of derivatization by ninhydrin rather than phthalaldehyde or dansyl chloride are discussed.
Amino Acids HPIC Spectrophotometry Post-column derivatization

"Simultaneous Determination Of Iron, Copper And Cobalt In Food Samples By CCD-diode Array Detection-flow Injection Analysis With Partial Least Squares Calibration Model"
J. Phys: Conf. Ser. 2006 Volume 28, Issue 1 Pages 66-69
Jianping Mi, Yuanqian Li*, Xiaoli Zhou, Bo Zheng and Ying Zhou

Abstract: A flow injection-CCD diode array detection spectrophotometry with partial least squares (PLS) program for simultaneous determination of iron, copper and cobalt in food samples has been established. The method was based on the chromogenic reaction of the three metal ions and 2- (5-Bromo-2-pyridylazo)-5-diethylaminophenol, 5-Br-PADAP in acetic acid - sodium acetate buffer solution (pH5) with Triton X-100 and ascorbic acid. The overlapped spectra of the colored complexes were collected by charge-coupled device (CCD) - diode array detector and the multi-wavelength absorbance data was processed using partial least squares (PLS) algorithm. Optimum reaction conditions and parameters of flow injection analysis were investigated. The samples of tea, sesame, laver, millet, cornmeal, mung bean and soybean powder were determined by the proposed method. The average recoveries of spiked samples were 91.80%~100.9% for Iron, 92.50%~108.0% for Copper, 93.00%~110.5% for Cobalt, respectively with relative standard deviation (R.S.D) of 1.1%~12.1%. The sampling rate is 45 samples h-1. The determination results of the food samples were in good agreement between the proposed method and ICP-AES.
Clonidine Cobalt Copper Spectrophotometry Partial least squares Triton X Method comparison Optimization