Solar Irradiation of Bilirubin: An Experiment in Photochemical Oxidation
A. E. Pillay
Department of Chemistry, College of Science, Sultan Qaboos University, Al Khoud, 123, Sultanate of Oman
F. M. Salih
Department of Clinical and Biomedical Physics, College of Medicine and Health Sciences, Sultan Qaboos University, Al Khoud, 123, Sultanate of Oman
An experiment on photochemical oxidation employing solar irradiation of bilirubin followed by spectrophotometric absorption was designed. Students can benefit from appreciating the utility of solar rays and its implementation in obtaining parameters such as chemical reaction rates and half-life. The experiment is student-friendly and involves solar irradiation of the sample in NaOH with absorption measurements at 453 nm. The bilirubin undergoes depletion, and the declining concentration can be expressed exponentially as a function of time. The instantaneous reaction rates, half-life, and rate constant can be derived directly from the exponential plot. Possible factors that affect the reaction, such as autooxidation and thermal effects, can be included in the experiment. The procedure is facile and didactic from the perspective of kinetics and from the prospect of isolating the photoproduct (biliverdin), which is a useful component in biosynthetic research.
A detailed student handout including procedures, reagents, equipment list; instructor's notes; examples of spectra; and questions and answers are available.
Pillay, A. E.; Salih, F. M. J. Chem. Educ.2006, 83, 1327.
Keywords
Applications of Chemistry; Bioanalytical Chemistry; Biochemistry; First-Year Undergraduate / General; Hands-On Learning / Manipulatives; High School / Introductory Chemistry; Laboratory Instruction; Organic Chemistry; Photochemistry; UV-Vis Spectroscopy
History
Created:
Last Updated:
8/7/2006
1/11/2008
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