Towards a less invasive future: Advancing Microneedle Biosensing for Melanoma Detection : Development of Conductive Microneedles and Optimization of Electrochemical Detection of MIA

Sammanfattning

Melanoma is an aggressive form of skin cancer with high mortality rates that necessitate improved early detection strategies. Conventional diagnostic methods are invasive and often limited by accessibility, prompting the need for minimally invasive, cost-effective alternatives. This thesis presents the development and preliminary evaluation of an electrochemical biosensing platform employing a molecularly imprinted polymer (MIP) strategy to target the melanoma-specific biomarker Melanoma Inhibitory Activity (MIA), with future integration envisioned into a wearable transdermal microneedle patch. The sensor utilized molecularly imprinted polyaniline coatings on graphene electrodes to enhance selectivity and sensitivity towards MIA detection. Electrochemical characterization revealed reproducible electrode activation and successful polymerization, though MIA rebinding responses were limited, indicating areas for optimization. In parallel, the microneedle array was designed and fabricated via CNC milling using polymethyl methacrylate (PMMA) as the base material due to its mechanical strength and biocompatibility. To enable electrochemical sensing, the microneedles were coated with a conductive polymer layer of PEDOT:PSS, ensuring effective transduction of electrochemical signals. Mechanical testing demonstrated sufficient structural integrity and penetration capabilities in skin simulants. These findings established a foundational framework for minimally invasive melanoma biosensing, emphasizing the need for further refinement in imprinting efficiency and microneedle functionalization. The integration of conductive polymers and microneedle technology represented a promising approach to advance early melanoma diagnosis, with potential to improve clinical outcomes.