SMART IMPLANTS WITH ON-DEMAND DRUG RELEASE: A REVIEW

Smart implants with on-demand drug release represent an advanced class of implantable drug delivery systems designed to overcome the limitations associated with conventional implants. Traditional implantable systems generally provide continuous drug release at fixed rates and lack responsiveness to changes in physiological or pathological conditions, which may result in inadequate therapy or increased adverse effects. Smart implants are engineered to release therapeutic agents selectively in response to specific endogenous physiological signals or externally applied stimuli. These systems utilize stimuli-responsive polymers, hydrogels, biodegradable matrices, nanomaterials, and microelectronic components to achieve controlled and precise drug delivery. Endogenous triggers such as pH variation, enzymatic activity, glucose concentration, and inflammatory mediators, as well as exogenous stimuli including light, magnetic fields, ultrasound, and electrical signals, have been extensively investigated for regulating drug release. Smart implants have shown significant potential in cancer therapy, diabetes management, infection control, ocular drug delivery, neurological disorders, and chronic disease treatment. This review discusses the principles, mechanisms, materials, classification, fabrication techniques, therapeutic applications, advantages, limitations, and future perspectives of smart implants with on-demand drug release, highlighting their importance in the development of precision and personalized medicine.