BIOSYNTHESIS OF SELENIUM NANOPARTICLES MEDIATED BY SPIRULINA PLATENSIS AND ASSESSMENT OF THEIR IN VIVO ANTICANCER EFFECTS IN WISTAR ALBINO RATS

Abstract

Selenium nanoparticles were successfully synthesized using Spirulina platensis extract by mixing 10 mL extract with 20 mL of 50 mM selenium solution and reducing with 200 µL of 40 mM ascorbic acid, producing a characteristic ruby red colour. The nanoparticles were further analysed for stability using particle size and zeta potential measurements. Acute oral toxicity studies (OECD 423) revealed no mortality or adverse effects at doses up to 2000 mg/kg. In vivo anticancer evaluation in DMBA-induced rats showed that SP-SeNPs (5 mg/kg) effectively reduced tumor progression, improved body weight, and demonstrated significant protective effects compared to cancer control. The formation of nanoparticles was confirmed by a characteristic ruby red color, indicating the reduction of selenium ions. Characterization studies revealed an average particle size of 84 nm with a zeta potential of −48.9 mV, demonstrating nanoscale formation, high stability, and good dispersion. Acute oral toxicity studies conducted as per OECD 423 guidelines showed no signs of toxicity or mortality at doses up to 2000 mg/kg, and histopathological analysis of liver and kidney tissues confirmed normal architecture, indicating biocompatibility. In vivo studies demonstrated that SP-SeNPs (5 mg/kg) significantly improved body weight compared to the cancer control group. Hematological parameters were restored, with RBC levels reaching 5.8 ×10⁶ cells/µL and WBC levels   8.5  ×10³   cells/µL.   Inflammatory  markers  were  markedly  reduced,  with TNF-α decreasing from 118.8 to 67.2 pg/mL, IL-6 from 95.0 to 49.2 pg/mL, and CRP from 6.88 to 3.02 mg/L following treatment. Histopathological evaluation of skin tissues showed near- normal epidermal and dermal architecture in SP SeNP-treated groups compared to severe alterations in cancer control. Overall, the findings indicate that SP-SeNPs possess significant anticancer, anti-inflammatory, and protective effects, highlighting their potential as a safe and effective therapeutic agent for skin cancer management.