Measuring of uremic substances in dialysate by visible ultraviolet spectroscopy

Abstract

We investigated the measurement of low molecular weight substances in dialysate by visible ultraviolet spectroscopy. The absorbance spectrum of creatinine and uric acid dissolved in fresh dialysate were clearly detected, however, that of urea was not clear. The spectrum of effluent dialysate collected during dialysis showed two peaks and those peaks matched to that of creatinine or uric acid. There were significantly correlation between actual concentrations of creatinine, uric acid in effluent dialysate and predicted concentrations by the absorbance spectrum of dialysate. While there was no correlation between actual and predicted concentration of urea .These data indicate that it is possible to predict the uremic substances in spent dialysate based on the absorbance spectrum of creatinine and ureic acid. The visible ultraviolet spectroscopy may be a useful method for noninvasive, reagentless and real-time measurement during hemodialysis treatment. © 2009 Springer-Verlag.