Ratio derivative-zero crossing and successive derivative of ratio spectra for simultaneous determination of urea, creatinine, and uric acid in human urine samples

ABSTRACT. Two simple precise and accurate spectrophotometric techniques are developed for simultaneous determination of ternary mixture of urea, creatinine, and uric acid in humane urine sample. The first technique is a ratio derivative zero - crossing where measured urea at 216.61 nm, creatinine  at 260.56 nm, and uric acid at 283 nm. The second technique is a successive derivative of ratio spectra where urea, creatinine, and uric acid measured at 203 nm, 261 nm, and 283 nm, 287 nm, respectively. These procedures do not need separation. The proposed methods showed excellent linear range over the concentration ranges of 1.0–15.0 μg/mL, 1.0–16.0 μg/mL, and 2.0–15.0 μg/mL for urea, creatinine, and uric acid, respectively. The recoveries ranged from 97.10% to 101.9% for urea, 97.22% to102.70 % for creatinine, and 97.45% to102.55 % for uric acid with relative standard deviations less than 1.56% for urea, 3.87% for creatinine, and 3.71% for uric acid. The analytical eco-scale and green analytical procedure index tools were used to evaluate how the proposed procedures will affect the environment. The simultaneous quantification of urea, creatinine, and uric acid in human urine samples can be accomplished with remarkable effectiveness by using the suggested approaches.   KEY WORDS: Urea, Creatinine, Uric acid, Derivative spectrophotometry Bull. Chem. Soc. Ethiop. 2023, 37(4), 817-829.                                                            DOI: https://dx.doi.org/10.4314/bcse.v37i4.2