Vaishnavi Adsul* 1
Dr. Swapnil phade 1
Pratik Bhabad 2
1.1 The Need for Solubility Enhancement in Drug Development
One important aspect impacting a drug's absorption and bioavailability is its solubility in aqueous solutions. Poor solubility affects about 40% of novel drug candidates, which restricts their potential for therapy and makes formulation more difficult [1]. For BCS Class II medications, which have high permeability but very little solubility, and BCS Class IV substances, which have both small pores and low solubility, poor solubility is a major obstacle for the pharmaceutical business [2]. The goal of pharmaceutical formulation strategies has long been to increase drug solubility using techniques including lipid-based systems, solid dispersion, and salt creation. But these methods frequently have drawbacks in terms of reliability, scalability, and regulatory approval. An inventive solution to these problems that preserves the drug's chemical stability is co-crystal formation.
1.2 Introduction to Co-Crystals
A substance called an API and a co-former molecule combine to form crystalline complexes known as co-crystals. In contrast to salts, which are made up of ionic contacts, co-crystals are usually made up of neutral molecules bound together by non-covalent connections like van der Waals forces, π-π stacking, and hydrogen bonds. [3]. Because co-crystals provide a way to change a medication's chemical and physical characteristics without affecting its pharmacological activity, they have drawn more attention in the drug development process. Co-crystals created by joining a medication molecule with a co-former may show:
• Increased solubility and rate of dissolution [4].
• Enhanced stability in a range of environmental circumstances [5].
• Release profiles were modified [6].
Co-crystal formation enables a more precise method of medication formulation, maximizing both patient compliance and therapeutic efficacy.
2. Co-Crystal Formation and Mechanism
10.5281/zenodo.15400763