Optimasi Carbopol 940 dan Gliserin terhadap Sifat Fisik Gel Ekstrak Etanol Daun Iler (Coleus scutellarioides (L.) Benth) Menggunakan Metode Desain Faktorial

Abstract

Background: Iler leaves contain flavonoids, saponins, tannins, and steroids that can accelerate wound healing. The formulation is made in gel form because it spreads faster on the skin, provides longer contact time for the drug, and protects the wound from external contamination. In this study, formula optimization was conducted by varying the gel additives, namely carbopol 940 as the gelling agent and glycerin as the humectant, to observe their effects on the physical properties and physical stability of the gel formulation. Objective: To determine the influence of the composition of carbopol 940 (gelling agent), glycerin (humectant), and their interactions on the physical properties of the gel formulation of Iler leaf extract, as well as to find the optimum composition. Methods: The research stages included plant identification, sample collection, sample processing, extract preparation, characterization of the plant material and extract, phytochemical screening of the extract, formulation of the gel formulation with 10% ethanol extract of Iler leaves, evaluation of the formulation, and formula optimization. Formula optimization was designed using a 2-factor and 2-level factorial design, with carbopol 940 at levels of 0.5% and 1%, and glycerin at levels of 5% and 10%. Evaluation of the formulation included organoleptic evaluation, homogeneity, spreadability test, viscosity test, pH determination, cycling test, and stability at room temperature. The optimized parameters analyzed were the physical properties and physical stability using Design Expert® version 11. Results: The characterization of the plant material and extract met the requirements of the Herbal Pharmacopoeia. The Iler leaf extract contained compounds such as flavonoids, saponins, tannins, glycosides, and steroids/triterpenoids. The evaluated gel formulation was homogeneous, had a pH within the range of skin pH (4.5-6.5), viscosity within the range of 2,000-4,000 cP, and spreadability within the range of 5-7 cm. The gel formulation remained stable during 12 weeks of storage and cycling test. Carbopol 940 and glycerin influenced the physical properties and physical stability of the gel. Carbopol 940 resulted in a decrease in spreadability by 85.25%, an increase in viscosity by 95.68%, and an increase in stability by 95.13%. Glycerin resulted in an increase in spreadability by 11.83%, a decrease in viscosity by 4.28%, and a decrease in stability by 0.12%. There was no interaction between carbopol 940 and glycerin on the physical properties and physical stability of the formulation. The optimum formula composition obtained was carbopol 940 at 0.82% and glycerin at 9.30%. Conclusion: The optimization of the formulation in the gel formulation of Iler leaf ethanol extract using carbopol 940 and glycerin affected the physical properties and physical stability of the formulation. The recommended optimum composition for a good formula result was carbopol 0.82% and glycerin 9.30%.