Engineering smart PLGA carriers: Surface design for multifunctional delivery of therapeutics and nutraceuticals

Poly (lactic-co-glycolic acid) (PLGA) is widely used in delivery systems due to its excellent biocompatibility, biodegradability, controllable drug release profile, and low toxicity, which can be fabricated into microspheres (MPs) or nanoparticles (NPs) for encapsulating food functional factors and pharmaceuticals. However, unmodified PLGA carriers often face challenges, including an initial burst release, poor targeting specificity, sensitivity to physiological pH variations, short retention time at target sites, and obstruction by biological barriers. Surface coating modification has emerged as a predominant strategy to overcome these limitations. This review comprehensively summarizes the types and functions of common coating materials, introduces the key evaluation metrics for assessing modification efficacy, and outlines the relevant preparation techniques along with their respective advantages and disadvantages. Furthermore, it discusses the impact of surface engineering on the stability and bioactivity of loaded cargoes, highlighting cutting-edge applications in the delivery of food functional factors and precision pharmaceuticals. Finally, the review identifies current constraints in the field, such as Lack of systematic reviews, drawbacks in preparation processes, and a lag in the development of novel materials, thereby suggesting focused directions for future research.