Dalton, ColinLijnse, Thomas2024-04-302024-04-302024-04-22Lijnse, T. (2024). Scalable production of low-cost microneedle technologies for drug delivery and biosensing applications (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.https://hdl.handle.net/1880/118465https://doi.org/10.11575/PRISM/43307Needles are a mainstay of modern healthcare, being used for drug delivery, biosampling, application of wearable technology, and measurement of biopotentials. Unfortunately, the use of needles comes with significant drawbacks, most importantly pain and anxiety associated with their use. Needle-phobia impacts nearly 60% of the American population and in severe cases will lead to avoidance of medical care and mismanagement of chronic conditions such as diabetes. Microneedles enable biosensing, drug administration, and other needle-functions, using small microprojections less than 1 mm in length. These tiny structures pierce the outer layers of the skin without reaching the deeper nervous tissues, rendering them effectively painless. Microneedles stand to alleviate significant mental burden on patients, economic burden on the healthcare system through avoidance of care, and deliver effective care to rural and remote populations. These advantages in mind, microneedle fabrication to-date has typically required either the use of expensive and low-throughput cleanroom microfabrication technologies, or bulkier commercial systems such as laser cutters and 3D printers which sacrifice microneedle efficacy for cost and material properties. There is presently no mass manufacturing ready, low-cost, scalable, cleanroom free strategy for making microneedles that are sharp, painless, and biosafe. This thesis describes the development of a novel fabrication process for solid metallic microneedles using an adapted electronics industry process known as wirebonding. Using this process, a fabrication protocol was developed to create a rapid manufacturing platform for low-cost, less than $2 per microneedle array, with high regularity (tip radii on order of ~10s of nm, geometry control on the order of ~10s of micrometers). The platform technology was evaluated to assess their insertion efficacy, drug delivery capabilities, and use as a biosensing technology. The fabrication method shown in this work is a novel, scalable technique for the development of high-density pain-free solid metal microneedle arrays, with ~1N array insertion forces, to be used to address the health and wellbeing of patients suffering from needle-phobia and chronic conditions.enUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.MicroneedlesDrug DeliveryBiosensingMicrofabricationWirebondingEngineering--Biomedicaldoctoral thesis