d-Band Center of Rare Earth Oxides Determines Biotransformation-Induced Cell Membrane Damage

Using the d-band center as a mechanism-drivendescriptor, a universal structure-activity relationship ofthe membrane-damaging capability of REOs was built. Biotransformation of rare earth oxide (REO) nanoparticleson biological membranes may trigger a series of adverse health effectsin biosystems. However, the physicochemical mechanism of the complicatedbiotransformation behavior remains elusive. By investigating the distinctlydifferent biotransformation behavior of two typical REOs (Gd2O3 and CeO2) on erythrocyte membranes, we demonstratethat dephosphorylation by stripping phosphate from phospholipids correlateshighly with the membrane destructive effects of REOs. Density functionaltheory calculations decode the decisive role of the d-band centerin dephosphorylation. Furthermore, using the d-band center as an electronicdescriptor, we unravel a universal structure-activity relationshipof the membrane-damaging capability of 13 REOs (R (2) = 0.82). The effect of ion release on dephosphorylationand physical damage to cell membranes by Gd2O3 are largely excluded. Our findings depict a clear physicochemicalmicroscopic picture of the biotransformation of REOs on the nano-biointerface, providing a theoretical basis for safe application of REOs.

Automated summary

By using the d-band center as a descriptor, a universal structure-activity relationship of the membrane-damaging capability of rare earth oxide (REO) nanoparticles was established. The biotransformation behavior of two typical REOs (Gd2O3 and CeO2) on erythrocyte membranes was investigated, and it was found that dephosphorylation through stripping phosphate from phospholipids is closely related to the membrane destructive effects of REOs. Density functional theory calculations revealed the crucial role of the d-band center in dephosphorylation, and a universal structure-activity relationship of the membrane-damaging capability of 13 REOs was uncovered. The impact of ion release on dephosphorylation and physical damage to cell membranes by Gd2O3 was largely excluded. These findings provide a theoretical basis for the safe application of REOs and offer a clear physicochemical microscopic picture of their biotransformation on the nano-biointerface.