An integrated <i>in vitro</i> and <i>in silico</i> approach to assess targeted cytotoxicity against MDA-MB-231 triple-negative breast cancer cells with <i>Psidium guajava</i> peel-derived chitosan nanoparticles

Triple-negative breast cancer (TNBC) is a significant global health issue, with high mortality rates. The chemotherapeutic drugs currently used for TNBC have significant side effects, impacting both normal and cancer cells. In this study, we investigated a potential use of fruit peel extract of <i>Psidium guajava</i> (PGP) encapsulated with chitosan nanoparticles (CSNPs) to combat TNBC. The synthesized PGP-CSNPs were characterized using UV-vis spectroscopy, Fourier transform infra-red (FTIR) spectroscopy, TEM and GC-MS. The maximum loading capacity and encapsulation efficacy of PGP-CSNPs were found to be 72.5 ± 0.49% and 92.9 ± 0.10%, respectively. Furthermore, <i>in vitro</i> cytotoxicity was assessed, and the IC₅₀ value for PGP-CSNPs was 50.13 µg/mL. It was observed that PGP-CSNPs could induce apoptosis in MDA-MB-231 cells in dose-dependent manner. Furthermore, molecular docking was performed for bioactive compounds retrieved from PGP-CSNPs against human tumour suppressor proteins Bcl2, and results showed that the PGP-CSNPs had lower binding energy than cisplatin. This suggests that, the synthesized PGP-CSNPs have the potential to serve as a therapeutic agent for tackling TNBC. However, to validate its efficacy in human therapy, furthermore pre-clinical and clinical procedures should be examined, as this is an ongoing and significant step towards developing an effective and safe anticancer drug.