1 ORIGINAL ARTICLE DOI: 10.4274/tjps.galenos.2020.44452 DEVELOPMENT AND CHARACTERIZATION OF CONDUCTING POLYMER BASED HYDROGEL FOR WOUND HEALING APPLICATION Ravindra V. Badhe 1 *, Anagha Godse 1 , Ankita Shinkar 1 , Avinash Kharat 2 , Vikrant Patil 2 , Archana Gupta 2 , Supriya Kheur 2 1 Dr. D. Y. Patil Institute of Pharmaceutical Sciences and Research, Pimpri, Pune-411018, Maharashtra, India; 2 Regenerative Medicine Laboratory, Dr. D. Y. Patil Dental College and Hospital, Dr. D. Y. Patil Vidyapeeth, Pimpri, Pune- 411018, Maharashtra, (India). Corresponding author Ravindra V Badhe ravindra.badhe@dypvp.edu.in +91 9422432038 https://orcid.org/0000-0002-9919-8154 09.05.2020 02.11.2020 Abstract Introduction- The normal and chronic wound healing is a global challenge. In recent decades, electrotherapy for treating such wounds emerged as a novel and efficient technique. One of the important components in wound healing electrotherapy is the hydrogel which is applied on the wound to uniformly distribute the electric current. In this work we report the development and wound healing efficacy testing of vitamin D entrapped polyaniline-chitosan composite hydrogel for electrotherapy. Materials and methods- The vitamin D entrapped polyaniline-chitosan composite hydrogel was developed and characterized using morphological and physicochemical techniques like SEM, DSC, XRD, FT-IR, pH, conductance, viscosity, and porosity analysis. The biodegradation was studied using lysozyme and water uptake ability was studied using phosphate buffer. Vitamin D entrapment and release study was performed using ethanoic phosphate buffer. Cell adhesion, proliferation and effect of electrical stimulation was carried out by seeding dental pulp stem cells into the scaffolds and using MTT assay; the SEM images were taken to confirm the proliferation results. The wound healing efficacy of electrotherapy and developed hydrogel was studied on excision wound healing model in rats and scar free wound healing was further confirmed by histopathology analysis. Results- The developed hydrogel was optimized for composition as 1% w/v polyaniline and 2% w/v of chitosan composite. This hydrogel showed 1455 μA conduction, 98.97% entrapment efficiency and 99.12% release of vitamin D in 48 hrs. Optimized hydrogel formulation showed neutral pH of 6.96 and had 2198 CP viscosity at 26 0 C. Hydrogel showed 652.4 % swelling index and 100 % degradation in 4 weeks. The in-vitro cell culture studies performed on hydrogel scaffolds using dental pulp stem cells (DPSC) and electric stimulation strongly suggested that electrical stimulation enhances the cell proliferation in 3D scaffold environment. The in-vitro results were also supported by in-vivo excision wound healing studies suggesting electrical stimulation of the wound in the presence of the conducting hydrogel and growth factors like vitamin D heals the wound much faster (within 12 days) compared to non-treated control wounds (required 21 days for complete healing). Discussion- The results strongly suggest that the developed polyaniline-chitosan composite conducting hydrogel acts effectively as an electric current carrier to distribute the current uniformly uncorrected proof