Semi-quantitative surface enhanced Raman scattering spectroscopic creatinine measurement in human urine samples

This paper presents the development of a semi-quantitative method of measuring the creatinine biomolecule in human urine by the surface enhanced Raman scattering (SERS) technique. Creatinine is one of the major components of urine and can be used to represent the metabolic and renal function of the human body. The Raman signal of creatinine is enhanced by 50 nm Au nanoparticles. Raman spectra between 1400 and 1500 cm^-1 were analyzed to obtain the relationship between the SERS band area and creatinine concentration. The square of the correlation coefficient is 0.99 in artificial urine over the creatinine range 38.4-153.6 mg/dl. In a human urine experiment, a good linear correlation is observed over the creatinine concentration range 2.56-6.4 mg/dl. The square of correlation coefficient is 0.96.