Fast removal of Candida parapsilosis from hemodialysis dialysate using ultraviolet or visible light at nanoporous W/WO3 electrodes

Abstract

The quality of the water used in a hemodialysis process is critical, and several cases of contamination by C. parapsilosis have been reported in the literature. In addition, it is causing many deaths. The present work describes the use of W/WO3 nanoporous array electrodes to treat hemodialysis water, as well as acidic and basic dialysates without addition of any electrolyte by irradiation of visible or ultraviolet light and application of low bias potential. The efficiency of the technique was compared to photolytic and photocatalytic treatments, and it was shown to be at least 5 and 10 times faster, respectively, when the dialysate was spiked with 1.0 × 106 CFU mL-1 of C. parapsilosis, using Eapp=1.0V and UV/Vis irradiation. The best experimental conditions resulted in the inactivation of C. parapsilosis present in the dialysate within 1min and almost 40% degradation of the byproducts generated in the hemodialysis water due to cell lysis after 120min of treatment.