Albumin-coated cadmium oxide nanoparticles: synthesis, characterization, and In Vitro and In Vivo evaluation of their biological activity in triple-negative breast cancer

Abstract

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype characterised by the absence of oestrogen, progesterone, and HER2 receptors, limiting the effectiveness of targeted therapies. Conventional chemotherapy remains non-selective and is associated with systemic toxicity and poor bioavailability. This study investigated the synthesis, characterisation, and anti-TNBC therapeutic potential of albumin-coated chemically synthesised cadmium oxide nanoparticles (A-Chem CdO NPs) as a potential nanotherapeutic strategy. Cadmium oxide nanoparticles were synthesised using green, chemical, and albumin-assisted chemical methods, and characterised using UV-Visible spectroscopy, FTIR, XPS, and TEM analyses. In vitro cytotoxicity was evaluated using the MTT assay, while in vivo therapeutic efficacy and systemic toxicity were assessed in a BALB/c mouse model using clinical observations, body mass changes, tumour inhibition rate (TIR), and histomorphological analysis. Chemically synthesised Cadmium Oxide Nanoparticles (Chem CdO NPs) demonstrated the highest in vitro potency and were subsequently functionalised with albumin to improve stability and biocompatibility. Albumin coating reduced the potency in MDA-MB-231 cells, whiththe IC50 increasing from 3.33 μg/mL to 11.32 μg/mL, whereas Doxorubicin (the standard drug) exhibited the greatest potency with an IC50 of 0.34 μg/mL and the highest selectivity index. In vivo, A-Chem CdO NPs induced delayed and milder clinical toxicity compared with Doxorubicin. Although body mass loss was comparable between treatments, Doxorubicin achieved superior tumour inhibition (50–55%), while A-Chem CdO NPs demonstrated moderate antitumour activity (30–35%). Histomorphological analysis revealed tumour necrosis and chromatin condensation in A-Chem CdO NP-treated tissues, indicating moderate tumour regression, with minimal evidence of off-target organ toxicity. Overall, the findings demonstrate that albumin functionalisation altered the biological behaviour of CdO nanoparticles, reducing acute cytotoxicity while maintaining moderate in vivo antitumour efficacy. These results highlight the complexity of nanoparticle therapeutic performance and support further optimisation of albumin-coated CdO nanoparticle systems for TNBC treatment.