Exploring the structural, morphological and optical properties of iron based metalloporphyrin in the nano regime for biomedical applications.

Iron-Based metalloporphyrin Fe-TCPP (iron (III) tetra(4-carboxyphenyl) porphyrin) is a promising photosensitizer utilized in photodynamic therapy (PDT). In this work, the structural, morphological, optical, and cell viability characteristics of Fe-TCPP nanoparticles (NPs), were thoroughly investigated in the present study. Structural characterization using X-ray diffraction, FTIR, and Raman spectroscopy confirmed the successful synthesis and coordination environment of the iron center within the porphyrin ring. Morphological analysis by FESEM revealed a dot-like structure of FeTCPP NPs with an average particle size of 26 nm, which further assembled to form rod-like shapes with a diameter of 0.1733 μm. While EDX analysis validated the elemental analysis, TGA studies provided insight into the thermal stability of FeTCPP NPs. Optical properties were investigated through UV-visible absorption and photoluminescence spectroscopy, and the third-order non-linear optical properties, along with the optical limiting behavior, were carried out by the Z-scan technique using a Q-switched Nd: YAG laser with 5 ns pulses at 532 nm. Furthermore, the biocompatibility of the compound was assessed against the L929 cell line, which revealed the non-toxic behaviour of the synthesized FeTCPP nanoparticles. The NLO property together with the high biocompatibility of the FeTCPP nanoparticles makes them an ideal candidate for PDT applications. The photodynamic potential of the nanoparticles was evaluated through intracellular reactive oxygen species (ROS) generation and in vitro cytotoxicity studies. The anticancer efficacy was assessed against A549 lung cancer cells using the MTT assay under both dark and irradiated conditions.