Nanoemulsion hydrogel delivery system of Hypericum perforatum L.: In silico design, in vitro antimicrobial–toxicological profiling, and in vivo wound-healing evaluation

Abstract

Hypericum perforatum L. (H.P.), a plant renowned for its wound-healing prop erties, was investigated for antioxidant/antimicrobial efficacy, toxicological safety, and in vivo wound-healing effects in this research to develop and characterize novel na noemulsion hydrogel (NG) formulations. NG were prepared via emulsion diffusion– solvent evaporation and polymer hydration using Cremophor RH40 and Ultrez 21/30. A D-optimal design optimized oil/surfactant ratios, considering particle size, PDI, and drug loading. Antioxidant activity was tested via DPPH, ABTS+ , and FRAP. Tox icological assessment followed HET-CAM (ICH-endorsed) and ICCVAM guidelines. The optimized NG-2 (NE-HPM-10 + U30 0.5%) demonstrated stable and pseudoplastic flow, with a particle size of 174.8 nm, PDI of 0.274, zeta potential of −23.3 mV, and 99.83% drug loading. Release followed the Korsmeyer–Peppas model. H.P. macer ates/NEs showed potent antioxidant activity (DPPH IC50: 28.4 µg/mL; FRAP: 1.8 mmol, Fe2+/g: 0.3703 ± 0.041 mM TE/g). Antimicrobial effects against methicillin-resistant S. au reus (MIC: 12.5 µg/mL) and E. coli (MIC: 25 µg/mL) were significant. Stability studies showed no degradation. HET-CAM tests confirmed biocompatibility. Histopathology revealed accelerated re-epithelialization/collagen synthesis, with upregulated TGF-β1. The NG-2 formulation demonstrated robust antioxidant, antimicrobial, and wound-healing efficacy. Enhanced antibacterial activity and biocompatibility highlight its therapeutic potential. Clinical/pathological evaluations validated tissue regeneration without adverse effects, positioning H.P.-based nanoemulsions as promising for advanced wound care.