Formulation and Physical Evaluation of Hydrogel Extract Combination of Centella asiatica and Moringa oleifera using Simplex Lattice Design Method

Abstract This research aims to develop an optimal hydrogel formula using Design Expert 13.0 and the Simplex Lattice Design (SLD) method. The hydrogel combines Centella asiatica and Moringa oleifera extracts with carbopol 940 as a gelling agent and triethanolamine (TEA) as an alkalizer. Hydrogels were chosen due to their ease of use, cooling effect, and superior biocompatibility compared to other topical formulations like ointments or creams. The study focused on optimizing the formula to meet Indonesian National Standards (SNI). After eight hydrogel formula trials using the SLD method, physical evaluations were conducted, including organoleptic tests, pH measurements, spreadability, and viscosity tests. The optimal formula contained 0.6% Carbopol and 0.4% TEA, validated with three replications. The hydrogel exhibited a deep green color, a distinctive extract aroma, and a thick texture, meeting SNI standards with an average pH of 7.1±0.29, spreadability of 5.7±0.21 cm, and viscosity of 20,080±0.35 cPs. Stability tests confirmed its quality after cycling and centrifugal evaluations. This study promotes sustainable and eco-friendly practices by utilizing natural extracts, reducing reliance on synthetic chemicals, and contributing to environmentally conscious topical drug innovations. The development of such hydrogels aligns with sustainability goals, offering biodegradable and safe formulations that minimize environmental impact.