Arginine-linked solid basil polyphenol self-assembly stabilizes Pickering nanoemulsions: In vitro oxidative stress relief and early evidence of in vivo nephroprotection.

This study reports the development of a hierarchical arginine-based colloidal network within a Pickering nanoemulsions stabilized by basil extract polyphenols (PEMA). Heat-induced citric acid-polyphenol complexes drive colloidal self-assembly and adsorption at the oil-water interface. To refine the microstructure, polyol-surfactant co-stabilizers modulated interfacial tension and osmotic pressure, directing the assembly of a dense interfacial layer. Integrating arginine significantly enhances physical stability and antioxidant potency, facilitated by a network of hydrogen bonds and electrostatic interactions. The arginine-linked colloids exhibited pH-dependent mucoadhesive interactions with gastric mucin and maintained cellular redox balance in RAW 264.7 macrophages under oxidative and inflammatory stress. These results suggest that the structural properties of arginine, specifically its cationic guanidinium group and hydrophobic propyl moiety, provide a chemical basis for enhanced mucoadhesion, facilitating gastrointestinal retention and potential cytoplasmic delivery. Systemically, PEMA attenuated oxidative damage induced by gentamicin-piroxicam in vivo, as evidenced by a 37 % reduction in thiobarbituric acid reactive substances (TBARS) and an 88 % increase in cupric reducing antioxidant capacity (CUPRAC). Importantly, PEMA treatment attenuated renal and liver injuries, as demonstrated by decreased serum creatinine (SCr), blood urea nitrogen (BUN), and transaminase levels (AST/ALT). Histological periodic acid-Schiff (PAS) staining confirmed that PEMA supports the structural integrity of the renal brush border membrane (BBM). Even though tubular recovery was incomplete compared to controls, PEMA demonstrate potential as a promising colloidal formulation for treating oxidative stress-related conditions.