CHARACTERISTICS OF EUGENOL PRODUCTS AND IN VITRO RELEASE IN GEL BASE WITH HYDROXYPROPYL METHYLCELLULOSE (HPMC) VARIANT AS GELLING AGENT Original Article SHOLICHAH ROHMANI 1* , ADI YUGATAMA 2 , ISTI WIJAYANTI 2 , DIAN EKA ERMAWATI 1 , ANIF NUR ARTANTI 1 , WISNU KUNDARTO 1 , M. FIQRI ZULPADLY 1 1 Department of Pharmacy, Pharmacy Diploma Study Program, Vocational School, Sebelas Maret University, Surakarta, Indonesia, 2 Department of Pharmacy, Bachelor of Pharmacy Study Program, Faculty of Mathematics and Natural Sciences, Sebelas Maret University, Surakarta, Indonesia Email: licha.apt@gmail.com Received: 08 Jun 2021, Revised and Accepted: 01 Sep 2021 ABSTRACT Objective: This research was conducted to examine the characteristics of the eugenol gel preparation in the Hydroxypropyl Methylcellulose (HPMC) gel base and to determine the profile of the release of eugenol from the HPMC gel base. Methods: Eugenol was made into gel preparations using HPMC base with concentrations of 3%, 5% and 7%. The evaluation included the tests of product characteristic and eugenol release. The product characteristic test included organoleptic examination (texture, color, and odor) and tests of spreadability, adhesion, and pH. The release test was carried out using cell diffusion and cellophane membranes. Results: All formulas met the pH requirements of topical products that were safe to use. The spreadability test is between 2.97-6.27 cm, adhesion test of products>4 s. The percentage of determination of eugenol content in the gel formula (F1 105.81%), (F2 93.28%) and (F3 98.87%). The cumulative amount of eugenol was F1 (2.563 mg/cm2), F2 (2.224 mg/cm2), and F3 (1.895 mg/cm2). Conclusion: The variation of HPMC as a gel base has effects on the adhesion, spreadability, and the eugenol gel release profile, where the greater the HPMC concentration, the smaller the spreadability, the greater the adhesion, and the lower the eugenol release profile. Based on the data obtained, the Formula 1 had a better release rate. Keywords: Eugenol, Gel, Hydroxypropyl methylcellulose, Release profile © 2021 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (https://creativecommons.org/licenses/by/4.0/) DOI: https://dx.doi.org/10.22159/ijap.2021v13i6.42351. Journal homepage: https://innovareacademics.in/journals/index.php/ijap INTRODUCTION Eugenol compound is widely researched and developed due to its various efficacies. The biological activities of eugenol are as antifungal, antibacterial, anti-carcinogenic, allergy, antioxidant, anti- mutagenic, and anti-insecticidal [1]. Apart from being used in the medical field, eugenol is also widely used in industrial field such as industries of food, perfume, agricultural, textile, and others. To maximize more, the use of eugenol can be formulated into products that can increase the comfort while being used. One form of product that can be made using eugenol is gel. Gel is potentially better as a means of managing topical drugs than ointment, since gel is non-sticky, requires less energy for formulation, stable, and its aesthetic is good [2]. A good gel product can be produced by formulating several types of gelling agents, however, the most important thing to note is the selection of the gelling agent. In gel formulation, the gelling agent component is a critical factor that can affect the physical properties of the gel produced [3]. Hydroxypropyl methylcellulose (HPMC) gel base is the gelling agent often used in the production of cosmetics and medicines since it can produce clear gel, dissolves easily in water, and has low toxicity. In addition, HPMC produces gel that is neutral, clear, colorless, stable at pH 3-11, has good resistance to microbial attack, and provides good film strength when drying on the skin [4]. The results of previous research indicated that HPMC bases had good drug release rate and wide spreadability [2]. The test for the eugenol active substance release of gel base is intended to determine that the optimum product has been made. Several factors that need to be considered when penetrating drugs through the membrane include the type of base, the solubility of the active substance in the base, and the pH of the base. In vitro release of the active substance from the carrier is a more cost-effective method of characterizing drug absorption and penetration through the skin membrane [5]. However, there has been no study to formulate eugenol in HPMC gel base to compare its drug release profile. This research was conducted to examine the characteristics of eugenol gel preparation in HPMC gel base and to determine the eugenol release from the HPMC gel base. The evaluation included the tests of product characteristic and eugenol release. The product characteristic test included organoleptic examination (texture, color, and odor) and tests of spreadability, adhesion, and pH. The release test was carried out using cell diffusion and cellophane membranes. MATERIALS AND METHODS Materials Eugenol (Purchased from Merck, Indonesia), Glycerin (Purchased from Brataco, Indonesia), HPMC (Purchased from Brataco, Indonesia), Propylene glycol (Purchased from Brataco, Indonesia), Nipagin (Purchased from Brataco, Indonesia), distilled water (Purchased from Brataco, Indonesia), KH2PO4 (Purchased from Merck, Indonesia), NaOH (Purchased from Merck, Indonesia), Ethanol p. a (Purchased from Merck, Indonesia), Cellophane Membrane (Purchased from Merck, Indonesia). Formulation Method: the HPMC was dispersed in propylene glycol, then added distilled water completely, and stirred until homogeneous and fluffy (mass 1). The nipagin was dissolved in 96% ethanol, put into the mass 1, and stirred until homogeneous. The eugenol was dissolved with the remaining 96% ethanol, and added with propylene glycol, then stirred until dissolved, and then mixed into the base which had been formed, then stirred until homogeneous. International Journal of Applied Pharmaceutics ISSN- 0975-7058 Vol 13, Issue 6, 2021