Abstract
Central nervous system (CNS) disorders such as Alzheimer's disease, Parkinson's disease, epilepsy, brain tumors, and psychiatric illnesses remain major healthcare challenges worldwide. Effective treatment of these disorders is often limited by the presence of the blood-brain barrier (BBB), which restricts the transport of therapeutic agents into the brain. Microencapsulation has emerged as a promising drug delivery strategy capable of improving drug stability, protecting sensitive molecules from degradation, prolonging drug release, and enhancing therapeutic efficacy. Microcapsules consist of active pharmaceutical ingredients enclosed within polymeric matrices or shell structures, enabling controlled and targeted drug delivery. Various microencapsulation techniques including solvent evaporation, spray drying, coacervation, ionic gelation, and interfacial polymerization have been employed for the development of CNS drug delivery systems. Recent advances in biodegradable polymers, nanotechnology, and stimuli-responsive materials have further enhanced the performance of microencapsulated formulations. Applications of microencapsulation have demonstrated significant potential in the treatment of Alzheimer's disease, Parkinson's disease, epilepsy, brain tumors, and depression. Despite challenges related to large-scale manufacturing, regulatory approval, and long-term safety evaluation, ongoing research continues to improve the clinical applicability of these systems. This review discusses the role of microencapsulation in CNS drug delivery, preparation methods, therapeutic applications, recent advancements, and future perspectives.