Advancements and challenges in microneedle technology for transdermal drug delivery

The field of pharmaceutical sciences has witnessed a surge of advancements in transdermal drug delivery. This non-invasive approach offers several advantages, including improved patient compliance, avoidance of hepatic first-pass metabolism, and enhanced bioavailability. However, the skin’s barrier function poses a challenge, limiting the application to molecules with specific physicochemical properties. Recent advances have addressed transdermal delivery limitations through innovative physical enhancement strategies, with microscale needle arrays demonstrating exceptional therapeutic potential. The engineered microstructures generate temporary micropores across the skin barrier, enabling efficient drug absorption kinetics. Microneedle-based delivery systems offer substantial clinical advantages, including minimally invasive administration, enhanced therapeutic outcomes, superior patient adherence, and precise dosing capabilities. The present review comprehensively examines multiple aspects of microneedle systems, including historical development, novel designs, materials, fabrication, characterization, diverse applications, significant advancements, and critical challenges. Specifically, we discuss microneedle applications in vaccination, personalized medicine, sustained delivery, targeted delivery, biologics, cosmetics, and advanced therapy. Critical developmental challenges, including dimensional optimization, safety evaluation, toxicity, patient acceptance, manufacturing scale-up, regulatory compliance, and environmental sustainability, receive detailed analysis, accompanied by perspectives on future directions in this rapidly advancing field. Conclusively, microneedle technology holds significant potential for revolutionizing transdermal drug delivery, offering a viable alternative to traditional administration methods and enhancing patient care. Keywords: Microneedles, novel designs, fabrication, characterization, transdermal drug delivery