Current Perspectives on Biopolymer-Based Injectable Formulations

Review Article

Abstract

Parenteral drug delivery systems are critical for therapeutics with poor oral bioavailability or those requiring controlled, localized release. Natural polymers have gained significant attention as advanced excipients for these formulations. Their inherent biocompatibility, biodegradability, and structural similarity to biological macromolecules offer distinct advantages over synthetic counterparts. These biopolymers, including polysaccharides (e.g., alginate, hyaluronic acid, chitosan) and proteins (e.g., gelatin, collagen, silk fibroin), are fabricated into diverse injectable platforms such as in situ forming hydrogels, microparticles, and nanoparticle carriers. These systems facilitate sustained drug release, provide localized therapeutic action, and serve as scaffolds in regenerative medicine. The functional versatility of these polymers allows for chemical modification to create stimuli-responsive materials that release therapeutic payloads in response to specific physiological cues. Despite their promise, challenges related to batch-to-batch variability, potential immunogenicity, suboptimal mechanical properties, and difficulties in terminal sterilization persist. Current research focuses on developing purified, chemically modified biopolymers and hybrid systems that merge natural materials with synthetic counterparts or inorganic nanomaterials. These research efforts are paving the way for next-generation injectable therapies in areas including oncology, chronic inflammatory diseases, and tissue regeneration