Title: Addressing phosphate removal issues during peritoneal dialysis using colloidally stable iron oxide nanoclusters coated with tannic acid
Authors: Theo Lucante, Philippe Choquet , Joana Vaz-Ramos , Vincent Ball, Dominique Begin, Cedric Leuvrey, Vasiliki Papaefthymiou, Spyridon Zafeiratos, Ariane Zaloszyc, Sylvie Begin-Colin
DOI: 10.1016/j.apsusc.2025.164782
Date: 2025-09-30
Working Group: WG3
Grant Period: Grand Period 3
Grant Period Goal (number): GAPG-3
Covered deliverables from the MoU (number): 3.1.1; 4.1.1
Countries involved: France
Number of female/young/ITC coauthors: 4/1/1
Is the publication open access?: Yes
Is the publication co-lead by a YRI?: No
Abstract: Removal of chronic excess phosphates in blood is critical for patients suffering from end-stage renal disease
(ESRD). ESRD patients can be treated with peritoneal dialysis (PD), during which phosphates are transported
from the blood to a specific solution, named dialysate, introduced into their peritoneal cavity. However, phosphate
removal in PD is currently insufficient but could be improved by introducing in dialysate phosphate adsorbents.
Iron oxide nanoparticles are biocompatible and well-known effective phosphate adsorbents, but their
colloidal stability at physiological pH and adsorption capacity in high ionic strength aqueous media such as
dialysate are significant challenges. Here, we have evaluated the potential of tannic acid-coated iron oxide
raspberry-shaped nanoclusters (RSNs@TA) for improving phosphate adsorption in dialysate. We have investigated
the influence of the TA coating on phosphate adsorption by performing adsorption experiments with
uncoated and TA-coated RSNs. In parallel, we have studied the influence of electrolytes and compounds in
dialysate on phosphate adsorption by conducting experiments in pH 7 water and dialysate. The TA coating was
shown to provide a high colloidal stability to the nanoclusters and mitigates the inhibitory effect of electrolytes in
dialysate on phosphate adsorption. Indeed, electrolytes in dialysate decreased the phosphate adsorption on both
nanoclusters but especially on uncoated ones by disturbing phosphate outer-sphere complexes. Thus, RSNs@TA
demonstrated enhanced adsorption capacity compared to uncoated RSNs in dialysate (20.7 ± 6.4 mg P.g 1) and
in pH 7 water (26.4 ± 8.1 mg P.g 1). These results established RSNs@TA as promising adsorbents for phosphate
removal in dialysate during a PD process.
