Recently, significant attention has been directed towards digital image colorimetry DIC using mobile applications or available software programs, which offer the advantage of analyzing samples without the need for sophisticated instruments. One such image processing program is Image J, widely used for obtaining quantitative information from scientific images. Image J could measure the color intensities by quantifying of the RGB (red–green–blue) gray levels across the images of colored substances. These values are correlated to the color intensities through conversion to CMY (cyan–magenta–yellow) values which are proportional to the color intensities.

This study pioneers the use of Image J for the precise determination of uric acid levels, comparing its effectiveness with UV/VIS spectrophotometry and a mobile app (RGB Color Detector).

Uric acid, a metabolic product of purine breakdown in RNA and DNA, serves as an indicator of renal complications. Elevated levels can lead to conditions such as gout or urinary stones. Traditional methods involve chromatography and colorimetry, each with limitations.

In the study, Image J was utilized to analyze images captured by smart phone for successive concentrations of uric acid that were previously treated with phosphotungstate to develop a blue color. The proposed method has been applied for determination of uric acid in real urine using standard addition method and the results were compared with UV/VIS spectrophotometry as a reference method.

The study successfully employed Image J to determine uric acid levels in both artificial and real urine samples. The standard addition approach using Image J was compared with UV/VIS spectrophotometry, demonstrating the feasibility and accuracy of the proposed method.

Comparative analysis revealed Image J’s superiority over mobile apps for precise quantitative analysis. While mobile apps proved suitable for qualitative or semi-quantitative analysis, Image J eliminated the need for multiple trials to determine optimal channels.

The Image J approach offers easy monitoring of uric acid levels without specialized instruments, presenting a promising avenue for diverse applications beyond uric acid quantification. The method’s simplicity and accuracy make it applicable for various colorimetric tasks, including heavy metal determination and drug analysis.

This groundbreaking study establishes Image J as a powerful tool for quantitative uric acid determination, surpassing mobile apps in accuracy. The method’s simplicity and potential for diverse applications mark a significant advancement in smartphone-based colorimetric approaches in analytical chemistry.

Article written by Elagamy, S.H., Adly, L. & Abdel Hamid, M.A. Smartphone based colorimetric approach for quantitative determination of uric acid using Image J. Sci Rep 13, 21888 (2023).