Biocompatibility of Amoxicillin and Diclofenac Sodium Loaded Poly-lactic Acid Microspheres: A Descriptive Study

Abstract

The safety of any drug delivery system destined for intra-oral application extends beyond its pharmacological efficacy to include its interaction with living tissues and blood components. While localized drug delivery systems (LDDS) such as poly-lactic acid (PLA) microspheres have shown great promise for sustained release of therapeutic agents in dental and maxillofacial applications, their translation into clinical use depends on thorough biocompatibility validation. In particular, for use in extraction sockets—an environment rich in blood supply and active tissue remodelling—understanding the cellular and haematological responses to these biomaterials is critical.

This study demonstrated that diclofenac sodium–loaded PLA microspheres exhibit favorable cytocompatibility in fibroblast cultures at concentrations up to 125 µg/mL, indicating their potential for safe intraoral application in soft tissue environments such as extraction sockets. However, a marked increase in hemolytic activity at higher concentrations underscores the importance of controlled dosing and formulation optimization to minimize blood-contact cytotoxicity. The results suggest that while the microspheres are biocompatible with oral fibroblasts, caution must be exercised to avoid systemic exposure or high local concentrations that could compromise erythrocyte integrity. Future improvements, such as surface modification or co-polymer blending, may enhance the safety profile and broaden the clinical applicability of this localized drug delivery system.