Effect of palladium-zinc alloy nanozymes on an inflammatory chondrocyte model

Objective: To discuss the anti-inflammatory effect of palladium-zinc alloy (PdZn/C) nanozymes on an inflammatory chondrocyte model induced by hydrogen peroxide (H₂O₂). Methods: The PdZn/C nanozymes were synthesized and characterized. The PdZn/C nanozymes were assayed for simulated superoxide dismutase activity (SOD) and simulated catalase activity (CAT). The biocompatibility of PdZn/C nanozymes with chondrocytes was examined in vitro by cell counting kit-8 (CCK-8) assay. The H₂O₂-induced inflammatory chondrocytes were co-cultured with PdZn/C nanozymes, the reactive oxygen species (ROS) levels of inflammatory chondrocytes were assessed by ROS fluorescent probe, and immunofluorescence assay was performed to detect the protein expression levels of interleukin (IL) -1β and tumor necrosis factor (TNF) -α in inflammatory chondrocytes. Results: The successful synthesis of PdZn/C nanozymes was confirmed by transmission electron microscopy (TEM), X-ray diffraction (XRD) and zeta potential. The results of CCK-8 assay confirmed that PdZn/C nanozymes had good biocompatibility.The PdZn/C nanozymes had excellent SOD and CAT mimicking activities. The PdZn/C nanozymes were able to reduce the ROS levels as well as the expression of IL-1β and TNF-α proteins in the inflammation model. Conclusion: The PdZn/C nanozymes have good biocompatibility and can reduce the inflammatory response of chondrocytes, making them a promising anti-inflammatory nanomaterial.