This thesis investigates the development and application of advanced polymer-based drug delivery systems, focusing on enhancing therapeutic outcomes for conditions such as diabetes, cancer, sleep disorders, and bacterial infections.

The research explores the use of poly(2- hydroxyethyl methacrylate) (pHEMA) hydrogel microneedles for the transdermal delivery of metformin, demonstrating how tuning the composition of these microneedles can optimize
drug release profiles and penetration capabilities. Additionally, the potential of pHEMA microneedles for delivering bioactives, such as estradiol, melatonin, and meropenem, is evaluated, revealing their versatility in treating a range of medical conditions through minimally invasive methods.

Further investigations focus on the development of stimuli-responsive systems, particularly using polypyrrole-based interpenetrating polymer networks (IPNs) for controlled release of melatonin. These films, engineered with biopolymers such as sodium hyaluronate and pectin, provide tailored drug release profiles and offer significant promise for treating sleep disorders. The thesis also introduces a smart dual-mode device for melatonin delivery, combining light-
dependent resistance (LDR) and circadian rhythm (CR) systems to synchronize drug release with the body's natural sleep-wake cycles. This device represents a step toward personalized medicine, ensuring more precise and adaptive therapeutic solutions.

In conclusion, the work presented in this thesis provides innovative polymer-based platforms for transdermal and controlled drug delivery, demonstrating their potential to revolutionize treatment methods for a variety of medical conditions through personalized, minimally invasive systems.