Phytogenic MnFe2O4 nanoparticles derived from phyllanthus emblica for multifunctional applications: dye degradation, antibacterial activity, and latent fingerprint enhancement with MATLAB-based similarity analysis.

This study reports the green extract assisted synthesis of manganese ferrite (MnFe2O4) nanoparticles using Phyllanthus emblica fruit extract as a natural reducing and stabilizing agent to develop multifunctional nanomaterials for forensic, environmental, and antibacterial applications. The green synthesized nanoparticles were characterized using XRD, HRTEM-SAED, FESEM-EDAX, UV-DRS, FTIR and VSM analyses, confirming a cubic spinel structure, high crystallinity, average crystallite size of 29 nm, and a narrow optical Eg of 1.9 eV. Synthesized nanoparticles demonstrated effective latent fingerprint visualization on both porous and non-porous substrates. MATLAB-assisted image processing and comparative similarity analysis yielded computational similarity scores ranging from 92.41% to 100% under the implemented workflow. Furthermore, the MnFe2O4 nanoparticles exhibited efficient visible-light-driven photocatalytic degradation of MG dye, achieving approximately 94% degradation at 5 mg/L and 92% at 20 mg/L within 20 min. In addition, the nanoparticles showed concentration-dependent antibacterial activity against Staphylococcus aureus, Bacillus.sp, Escherichia coli, and Klebsiella.sp, with a maximum zone of inhibition of 9 mm against Bacillus.sp. The observed multifunctional behavior is attributed to the synergistic effect of nanoscale size, magnetic properties, and phytochemical functionalization. These findings demonstrate that green-synthesized MnFe2O4 nanoparticles are potential eco-friendly multifunctional nanomaterials for advanced forensic fingerprint analysis, wastewater treatment, and antibacterial applications.