In vitro determination of bilirubin in hemolysed whole blood using first derivative analysis

A spectrophotometric method is presented in this paper to demonstrate the authors' experimental results to measure bilirubin in hemolysed whole blood. The absorption spectra were taken using a HELLMA thin (0.1 mm) cuvette. Bilirubin measurement over a concentration range of 0.5 to 10 mg/dl was obtained from the composite absorption spectra with a normal hemoglobin concentration of 15g/dl. In the authors' experiment, they were able to demonstrate that by using first order derivative analysis with window averaging, the bilirubin absorption could be separated from the major absorption component contributed by hemoglobin in hemolysed whole blood samples. Using a wavelength range from 483 to 519 nm as an averaging window, the resulting linear regressions for bilirubin estimation at hemoglobin concentrations of 10, 12.5, and 15g/dl are found to be 0.9997, 0.9998, and 0.9994, respectively.