Development and optimization of a naproxen-chia seed oil emulgel for topical anti-inflammatory applications

Chronic inflammation is a significant health issue, with non-steroidal anti-inflammatory drugs (NSAIDs), such as naproxen, being commonly used to manage inflammatory skin conditions. However, naproxen poor solubility limits its therapeutic efficacy. This study aimed to develop a naproxen-chia seed oil-based emulgel to enhance the topical anti-inflammatory effect, improve drug permeation, and provide sustained drug release for managing skin inflammation. A Box-Behnken Design was employed to optimize the emulgel formulation, with Carbopol 934, chia seed oil, and Tween 80 as independent variables. The formulation was evaluated for viscosity, spreadability, drug content, in vitro release profile, antioxidant activity, and stability. The optimized emulgel demonstrated a particle size of 125.6 nm, a Zeta potential of −31.4 ± 1.2, a viscosity of 10,651 cP, spreadability of 3850 mm², and 79.6 ± 3.2% drug content. In vitro release studies revealed 81.3 ± 1.5% drug release over 24 h, compared to 93.2 ± 3.2% from pure naproxen, with Korsmeyer–Peppas model kinetics (R² = 0.9819). Stability tests showed stable pH (5.6–5.8) and drug content over 3 months, with minor pH changes at elevated temperatures. Additionally, chia seed oil enhanced antioxidant activity to 86.7 ± 1.5%, compared to 71.4 ± 0.7% for pure naproxen. The naproxen-chia seed oil emulgel effectively improves drug release and antioxidant properties, offering a promising topical delivery system for inflammatory skin conditions. Chia seed oil serves as a permeation enhancer and antioxidant, enhancing the overall therapeutic potential. Further in vivo and clinical studies are recommended to confirm its efficacy.