Indian Journal of Pharmaceutical Sciences Research Paper July-August 2022 848 Formulation Development and Evaluation of Lawsonia inermis Extract Loaded Hydrogel for Wound Dressing Application KOHINA DIXIT, DEBADATTA MOHAPATRA, P. C. SENAPATI 1 , R. PANDA 2 AND A. N. SAHU* Department of Pharmaceutical Engineering and Technology, Phytomedicine Research Lab, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh 221005, 1 Gayatri Institute of Science and Technology (GIST), Gunupur, Odisha 765022, 2 Bal Pharma Limited, Bangalore, Karnataka 560052, India Dixit et al. : Lawsonia inermis Hydrogel for Wound Dressing Plant based therapeutics have been extensively used for wound healing due to their faster healing rate and lesser side efects. The combinatorial approach of traditional concept with modern hydrogel-based drug delivery system can able to heal the wound in an accelerated manner. The present study aimed to formulate and evaluate the wound healing potential of hydrogel containing standardized ethanolic extract of Lawsonia inermis Linn. Ethanolic extract of leaves was prepared, standardized with respect to lawsone by validated high-performance thin-layer chromatographic method. The hydrogel formulations were prepared using Carbopol 934 in diferent concentrations (0.5, 1.0 and 2.0 % w/w), assessed for cosmetic persona, pH, viscosity, spreadability, occlusion, syneresis, drug content, drug-excipient compatibility, skin irritation and for its wound healing activity. The hydrogel formulations (F1, F2 and F3) were found to be clear, homogeneous, compatible, nonirritant in nature, with pH (6.73±0.047 to 6.8±0.082), spreadability (6.81±0.09 to 8.13±0.08 cm), viscosities (39840±500.07 to 87538±389.87 cp), occlusion factor values (57.43±1.24 to 73.82±2.48 %), percent syneresis (2.696±0.368 to 5.5±0.226), and percent drug content (94.271±0.292 to 96.587±0.402) were found to be optimal for topical application. Hydrogel (F2) exhibited a signifcant healing response in the excision wound rat model. Wound healing was signifcantly improved among the test groups on the 4 th , 8 th and 12 th d (p<0.001) in comparison to standard lawsone hydrogel and control group. The result showed that the studied hydrogel has the potential for wound dressing. Key words: Hydrogel, Lawsonia inermis, lawsone, high-performance thin-layer chromatography, wound healing Wound healing is a complex and dynamic tissue regeneration process that repairs injured skin and other soft tissues. Usually, it involves three temporally overlapping phases infammation, proliferation and remodeling [1] . The continuity of these three phases at a particular time for a specifc duration at an optimum intensity in proper sequence is a bio-physiological function [2] . After an injury, an infammatory response occurs and the cells under the dermis (the deepest layer of skin) begin to increase the production of collagen (connective tissue), later, the epithelial tissue (the outer layer of the skin) is regenerated [3] . Plants and their extracts have great potential in the administration and treatment of wounds. For fewer side efects and a quick healing rate, some herbal medicines have been widely used for the treatment of wounds since ancient times [4] . Lawsonia inermis (L. inermis) Lythraceae family, commonly known as henna or mehendi in Hindi. The leaves of L. inermis contain phenolic compounds such as coumarin, favonoids, naphthalene, naphthoquinones (lawsone, 2-hydroxy- 1,4-naphthoquinone), lignans, alkylphenones; non- volatile terpenes such as lupeol, botulin, betulinic acid and 30-norlupan-3β-ol-20-one; oleamide; trace elements such as Ca, Na, Mg, P, K, and Se; fat; resin; gallic acid and mucilage [5,6] . The color matter is assigned to the quinone, lawsone, accountable for the dyeing principle of the plant and also related to many of the pharmacological activities. The plant has long been used for medicinal and cosmetic purposes, which are extremely connected to the old and modern cultures of Asia and North Africa [5] . Besides being used *Address for correspondence E-mail: ansahu.phe@iitbhu.ac.in Accepted 08 July 2022 Revised 20 September 2021 Received 12 December 2020 Indian J Pharm Sci 2022;84(4):848-862 This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms