Spectrophotometric determination of ascorbic acid in coloured samples

This bachelor’s thesis deals with spectrophotometric determination of ascorbic acid after the xylen extraction in coloured samples. The theoretical part deals with reactions, biochemistry and occurrence of ascorbic acid in foodstuffs. Also, it is dealt with various methods of determination of ascorbic acid, such as HPLC methods, electrochemical methods, titrimetric determinations, spectrophotometric determinations or polarographic method. In the experimental part of this method were first determined the concentration of ascorbic acid in the standards, then in real samples (vitamin tablets, orange juice and the juice of cultivated varieties of elderberry). Some validation parameters of the method were also determined. Sensitivity of the method was determined to 1,6772, linearity to 0,9990, limit of detection was set at 0,0466 mg/ml and the detection limit at 0,1552 mg/ml. Accuracy of the method was expressed as relative standard deviation, which gained 3,00% in value