Multifunctional carboxymethylcellulose-based nanogel containing Matricaria chamomilla essential oil: A practical...

Skin aging is an inevitable biological process influenced by intrinsic factors and environmental stressors, particularly UVB radiation. This study developed a nanogel containing Matricaria chamomilla essential oil (MCEO) via a nanoemulsion method using Tween 20 and Tween 80 as surfactants and carboxymethylcellulose (CMC) as a gelling agent. The formulated nanogel was characterized for its physicochemical properties, including particle size and distribution (SPAN) by dynamic light scattering (DLS), morphology by transmission electron microscopy (TEM), viscosity by rheometry, and colloidal stability by zeta potential. Its functional efficacy was assessed through in vitro assays for antioxidant (DPPH), anti-enzymatic (collagenase and elastase inhibition), and antibacterial activity against common pathogens. The in vivo anti-photoaging effects were evaluated in a UVB-induced rat model. The nanogel formed stable, monodisperse particles with a mean diameter of 86 ± 2 nm, a SPAN value of 0.96, and a zeta potential of -27 ± 4 mV. It exhibited strong antioxidant activity (84 ± 2 % DPPH radical scavenging), inhibited collagenase by 48.2 % and elastase by 15.1 %, and showed significant antibacterial effects. Topical application on UVB-exposed rats resulted in markedly fewer wrinkles, improved preservation of epidermal architecture, enhanced tissue regeneration, and reduced inflammation compared to controls, as confirmed by morphological scoring and histology. These findings indicate that the MCEO nanogel exerts multifunctional anti-aging effects through antioxidant, anti-enzymatic, and antimicrobial mechanisms. The preclinical results support its potential for cosmetic and dermatological applications and justify further clinical investigation.