Structuring biogenic synthesis of rare phase LaMn2O5 using the Bauhinia variegata (Kachnar) flower extract for highly sensitive, long range electrochemical detection of bisphenol-A, an endocrine disruptor

This work presents the in situ biogenic synthesis of rare phase nanostructure LaMn2O5 by the hydrothermal method, using the Bauhinia variegata (Kachnar) extract to prevent the discharge of hazardous and toxic waste elements into the environment. In this study, the compound exhibits strong Mn-3p and O-2p interactions, closely associated with vacant La-4f orbitals resulting in strong covalent bonding. Moreover, the synergetic effect of the f–d block metals effectively facilitates electron transfer. In this work, biologically derived, rare phase LaMn2O5 was also fabricated as a bioelectrode and developed into an electrochemical sensor. The estimated biosensor was assessed across a wide range of analyte concentrations for detecting the plastic monomer and endocrine disruptor bisphenol-A (BPA). A three-step linear response was observed, spanning from 0.001 μM to 0.1 μM, 1.0 μM to 40 μM and 40 μM to 1000.0 μM with a limit of detection (LOD) value of 2.85 × 10−3 μM and negligible interference. The sensitivity was obtained to be 3.67 mA μM−1 cm−2. Cyclic voltammetry (CV), pH, and scan rate studies were also performed for the prepared nanomaterials. From the scan rate study, the diffusion coefficient (D), charge transfer rate (Ks), and surface concentration (γ) were calculated which were found to be appreciable. The synthesized rare phase nanostructure LaMn2O5 exhibited a response time of 30 seconds, 60 days long stability, and 13 times reusability. This study reveals the biogenic synthesis of rare phase nanostructure LaMn2O5. This innovative method has the potential to harness natural resources for the synthesis of distinct nanomaterials. The rare phase nanostructure LaMn2O5 appears to be highly susceptible, in the long-range detection of BPA.