Phyto-mediated synthesis of SnO2 nanoparticles using Croton malabaricus Bedd. for its antioxidant, antibacterial, hemocompatibility properties and photocatalytic activity†

The phyto-mediated production of SnO₂ nanoparticles (Cm-SnO₂ NPs) was effected using the stem wood 50% ethanolic extract of Croton malabaricus Bedd. as a reducing agent. The extract was subjected to phytochemical characterization. The Cm-SnO₂ NPs were characterized using XRD, UV, FTIR, FE-SEM, EDX, AFM, and HR-TEM. HR-TEM and XRD measurements verified that the agglomerated, spherical nanoparticles had a crystallite size of 9.13 nm. The Cm-SnO₂ NPs were checked for their antioxidant, antibacterial, antibiofilm, haemolytic, and thrombolytic properties, effects on Cicer arietinum, and photocatalytic degradation of sunset yellow dye. The plant extract contained phenols (438.98 ± 0.82 mg GAE per g DW), flavonoids (64.02 ± 0.34 mg QE per g DW), and terpenoids (76.42 ± 0.44 mg linalool per g of extract DW). The IC₅₀ values for the DPPH and Fe chelating activities of Cm-SnO₂ NPs were 17.47 ± 0.9 and 20.98 ± 0.5 μg mL⁻¹, respectively. At 100 μg mL⁻¹, the highest antibacterial activity (32 ± 0.26 mm) and antibiofilm activity (33.05 ± 0.6%) of Cm-SnO₂ NPs were seen against K. pneumoniae. The nanoparticles were found to be least toxic toward RBC suspensions (IC₅₀ = 0.732 mg mL⁻¹) and to have significant clot lysis activity (62.04%). The Cm-SnO₂ NPs showed a growth-stimulatory effect on the seeds of Cicer arietinum by increasing the germination percentage from 56.66% at 24 hours to 73.33% at 48 hours. The Cm-SnO₂ NPs exhibited 60.47% photocatalytic degradation efficiency of sunset yellow dye under UV light conditions within 60 min. Thus, Cm-SnO₂ NPs can be effective for biological purposes, dye degradation, and crop growth promotion, contributing to both health and environmental aspects.