Efficient photocatalytic activity of Au@Mg nanospheres on mineralization of polystyrene: A sustainable remediation strategy on sunlight-induced photodegradation, environmental toxicity, and sensing of cefixime

The overexploitation of synthetic plastic materials has led to their accumulation in various ecosystems. This causes serious ailments and existential threat to biological entities of numerous hierarchical categories. The Au@Mg nanospheres were fabricated by ascorbic acid chemical reduction method and this material serves as a potential tool to mineralise plastic materials. TEM imaging of Au@Mg implies the Mg at core and Au at shell. The photocatalytic degradation of Au@Mg on polystyrene was studied and the effective degradation was found to be 97.1 %. The reusability of Au@Mg nanosphere was studied and the reusability efficiency was found to be 99.5 %. The OCl[rad] and [rad]OH radical plays a major role in the photocatalytic degradation of polystyrene. In addition, the good sensing assay on the detection of cefixime (CEF) was studied and it shows selective and sensitive detection towards CEF. The limit of detection of CEF by Au@Mg nanospheres was calculated to be 450 pM. The selectivity of the probe was further studied by interference and it has been observed that the detection was effective only in presence of CEF with metal drug mixture. In addition, the good sensing of Au@Mg nanospheres towards cefixime was studied by spiking it with blood serum and the recovery percentage was calculated to be 99.7 %. Genotoxicity of the polystyrene on Allium cepa was performed before and after degradation and the results didn't show any toxicity by the degraded product. Thus, the prepared bimetallic Au@Mg nanosphere serves as an effective sensor for the monitoring and optimization of CEF drug for the treatment of various microbial infections in human and as an effective photocatalytic material for the degradation of polystyrene.