Original Article DESIGN AND CHARACTERIZATION OF GLIBENCLAMIDE-CAFFEIC ACID COCRYSTALS VIA CRYSTAL ENGINEERING JYOTI MALIK 1,2 , HIMANSHU SACHDEVA 1 , ANURAG KHATKAR 1 , ARUN NANDA 1* 1 Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak (Haryana), India. 2 School of Pharmaceutical Sciences, Apeejay Stya University, Sohna Gurugram, (Haryana), India * Corresponding author: Arun Nanda; * Email: an_mdu@rediffmail.com Received: 06 Jul 2024, Revised and Accepted: 04 Dec 2024 ABSTRACT Objective: The present work aims to prepare and characterize glibenclamide cocrystals. Methods: Glibenclamide was chosen as a model drug due to its low solubility and classification as a Biopharmaceutical Classification System (BCS) class II drug. Among the various methods for selecting appropriate coformers, the pKa and thermal methods were employed. Using these approaches, a formulation with caffeic acid, prepared through the solvent evaporation method, demonstrated the best results as evaluated by parameters such as dissolution rate, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Hot Stage Microscopy (HSM), Scanning Electron Microscopy (SEM). Results: In the FTIR spectra, the sulfonamide group of the drug formed hydrogen bonds with the hydroxyl groups of the coformer, suggesting the presence of hydrogen bonding interactions between the components. HSM and DSC revealed that the melting point of the cocrystals occurred at a different temperature for the pure drug and coformer. This significant change in the melting point indicates the formation of a new crystalline phase in the cocrystals, suggesting that the drug and coformer interact at the molecular level to form a unique solid structure. XRD analysis showed diffraction peaks at distinct points with higher intensity in the cocrystals, indicating a new crystalline structure. SEM images of the cocrystals revealed a well-defined crystalline morphology, which differed from the irregular shapes of the pure drug and coformer. The cocrystals demonstrated a significantly improved dissolution rate compared to the pure drug and marketed formulation. In animal studies conducted on male Wistar rats, cocrystals reduced blood glucose levels more rapidly than pure glibenclamide. This enhanced antidiabetic efficacy suggests that the cocrystal formulation not only improves dissolution but also accelerates the therapeutic onset of action. Conclusion: These findings confirmed that the glibenclamide cocrystals prepared with caffeic acid help effectively improve the drug’s low solubility. Keywords: Cocrystals, Glibenclamide, Caffeic acid, Solubility, Co-former, Solvent evaporation method © 2025 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.2025v17i1.51992 Journal homepage: https://innovareacademics.in/journals/index.php/ijap INTRODUCTION After oral administration, the drug's solubility and dissolution rate are important factors in determining its rate and degree of absorption. This challenge poses a substantial hurdle for the pharmaceutical industry in developing and producing effective drugs [1]. Cocrystal technology has emerged as an innovative approach to enhance the solubility, dissolution rate, and bioavailability of Active Pharmaceutical Ingredients (APIs) while maintaining a stable crystalline form without modifying the API’s covalent bonds [2]. Cocrystals are crystalline complexes of active or neutral substances held together by non- covalent bonds, particularly hydrogen bonds, to create a defined crystalline lattice. The primary benefit of cocrystallization is that it preserves the essential medicinal properties of the active components while modifying certain physicochemical properties, such as melting point, solubility, and dissolution rate [3]. Cocrystal formation largely depends on two types of intermolecular interactions: heteromeric and homomeric combinations of components, with complementary functional groups, which likely explains the formation of supramolecular synthons in cocrystals. The selection of coformers is crucial in determining the final properties of cocrystals. In cocrystal preparation, coformers can enhance the stability and solubility of the API by altering its crystal structure. Coformer selection relies on two primary methods: experimental and knowledge-based approaches. The experimental method is largely trial and error [4], involving crystallization of the API with selected coformers and verifying cocrystal formation through analytical techniques such as Differential Scanning Calorimetry (DSC) and Powder X-Ray Diffraction (PXRD). Consequently, this approach can be very time and resource-intensive. Alternatively, knowledge-based strategies like hydrogen bonding, pKa considerations, supramolecular synthons, and Hansen solubility parameters provide a more systemic approach to coformer selection [5]. Glibenclamide (GLB) as shown in fig. 1, is GLB an oral sulfonylurea antidiabetic medication commonly used to manage type-2 diabetes by controlling blood glucose levels [6]. However, GLB has limited water solubility and its oral bioavailability is low, around 40-45%. Additionally, GLB has a relatively short biological half-life of 3-5 h and undergoes extensive first-pass metabolism in the liver, resulting in metabolites with minimal hypoglycemic effects [7]. Fig. 1: Structure of glibenclamide (drawn in ChemDraw software) International Journal of Applied Pharmaceutics ISSN- 0975-7058 Vol 17, Issue 1, 2025