Chemistry 365 BiochemistryLaboratory Unit #2Spectrophotometric Determination of Amino Acids with NinhydrinReferences:Lee, Y.P.; Takahashi, T. Anal. Biochem.1966, 14, pp 71-77.Robyt, J.F.; White, B.J. Biochemical Techniques Theory and Practice; Waveland: Prospect Heights,IL, 1990.Solutions:1) ninhydrin reagent - 63 % glycerol (volume), 37% 0.5 M citrate buffer, pH 6.5 containing 7.1 gninhydrin per liter.2)amino acid solutions - 0.002 M solutions of phenylalanine, glycine, and aspartic acidLaboratory:1)Prepare a blank by mixing 3.8 mL ninhydrin reagent and 0.2 mL distilled water.2)For each amino acid, prepare a range of four concentrations by mixing 3.8 mL ninhydrin reagent andvarying amounts of amino acid stock solution and water that add to 0.2 mL.3)Mix each solution well and heat in a boiling water bath for 45 minutes.4)Cool the solutions and read the absorbances versus the blank at 570 nm.Report:1)Write a brief summary of the experimentand spectrophotometric analysisin your notebook.
This is the end of the preview.
access the rest of the document.