Important features of spectrophotometers are spectral bandwidth and linear range of absorption or reflectance measurement. • To determine the concentration of extracted protein by different methods. 09/13/12 The purpose of this experiment is to conclude the concentration of an unknown solution using colorimetry to plot a calibration curve. Introduction 3 Results The measurement of light absorbance by a solution is also done with spectrophometer. Protein is a series of amino acids that are connected together by peptide bond. The intensity of the violet color is directly proportional to the protein concentration, according to the Beer-Lambert law. The copper sulfate was then added into different volumetric flasks with 10.0 mL of distilled water. BACKGROUND The determination of protein concentration is an essential technique in all aspects of protein studies and proteomics. Objectives 4 The absorption spectrum will show how much light is absorbed at each wavelength. Also, 10 drops of concentrated nitric acid were added to the solutions. Correctly evaluating the number of peptide bonds is a step towards determining the protein content of the sample. M = mol/vol CuSO₄ + 5H₂O CuSO₄ = 249.5896g The blue ye firsts donates free electron to the protein and causes the protein to lose its native state and exposing it hydrophobic pockets. If there is the appearance of bluish violet colour indicates the presence of protein. The purpose of this experiment was to determine the concentration of an unknown amount of copper sulfate using the spectronic 20. Cindy Zhou 10 | UK | 1000 | 10 | 39.9 | 1.085 | 0.13M 0.13M = mol/ 0.100L = 0.013 mol (249.5896g) = 3.245g The bond is located between the end of previous amino acid, which is the carboxyl group, and the head of next amino acid, which is a amino group. This dual sensitivity is useful to determine if the sample has complex... ... The Biuret Method, or biuret test, is used to detect the presence of peptide bonds. Conclusion 9 ID: 00000011136 Biuret test Principle of Biuret test: Biuret test is a general test for compounds having a peptide bond. The intensity of the violet color is directly proportional to the protein concentration, according to the Beer-Lambert law. Introduction: The quantitation of protein content is important and has many applications in clinical Background/Introduction: It is more specific than the general term electromagnetic spectroscopy in that spectrophotometry deals with visible light, near-ultraviolet, and near-infrared, but does not cover time-resolved spectroscopic techniques. INTRODUCTION A spectrophotometer is commonly used for the measurement of transmittance or reflectance of solutions, transparent or opaque solids, such as polished glass, or gases. 2 | STAN | 1000 | 4 | 2 | 0.090 | Please join StudyMode to read the full document. The Biuret reagent is a solution of copper sulfate and potassium hydroxide. The binding protein then stabilizes the blue form of the Coomassie dye. Absorbance at 540 nm for the Biuret and 750 nm for the Lowry assays. Discussion 7-8 The negative test result is that the solution remains dark blue. The method requires a spectrophotometer and it is easily operated. Apply this test to gelatin, casein and albumin. Determining the Protein Concentration of Turkey Using a Biuret Assay Introduction The purpose of this experiment was to determine the protein concentration in a sample of turkey. Data Collection: Worktable for Coomassie Assay Four different concentrated solutions of CuSO₄ (0.13M, 0.11M, 0.090M, and 0.070M) were prepared by crushing the copper sulfate with a mortar and pestle. TITLE : DETERMINATION OF ERYTHROSINE CONCENTRATION USING UV- VISIBLE SPECTROPHOTOMETER Dipeptides and amino acids do not give this reaction. Potassium Manganate (100g/ml), distilled water, colorimeter, cuvettes, test tubes, test tube rack, burette, pipette.