Developing Biocompatible & Bioabsorbable UV Materials Enabling Mass Production of Custom Medical Device Implants Using Micro-CLIP

Evan Baker and Henry Ware, Northwestern University

Abstract: The missing component for additive manufacturing technologies over the past 30 years has been production speed and part quality. That all changed last year when Carbon3D revealed CLIP manufacturing technology, implementing a simple design change to improve production speeds by 25-100 times with nearly uniform part quality. As emerging experts in the field, we built our own printer, modifying their technique and focused it down to resolutions of 7um per pixel to enable high resolution micro-devices and optics. This talk will focus on the printer we built and two types of devices we are developing. To set the stage, tens of thousands of Americans die each year from peripheral artery disease, a disease caused by blocked arteries, often from high sugar/fat food in our diets. For many patients their best option to improve blood-flow, reduce pain and save their limbs is to implant a stent, a thin patterned tube that presses outwards against the clot and vessel wall to open blood flow through the artery. Stents today are made out of metal, typically nickel titanium or stainless steel, and up to 44% of patients suffer from severe restenosis, a renarrowing of the vessel, as well as other complications such as stent thrombosis. Such complications cause the need to remove current stent and deployment of a new stent. In extreme cases this can lead to death. To alleviate this condition we are developing new polymer materials for our stents that absorb into the body over six to twelve months and that are compatible for mass production with the CLIP process. Additionally, our group has been developing a 3D printable HEMA based hydrogel ink. Hydrogels are polymeric materials able to absorb and hold large amounts of water within their structure. HEMA is a polymer that has existed for a large portion of the 20th century and has been used many applications such as dentistry, microfluidics, vascular implants, drug delivery, and contact lenses. To enable 3D designed, custom and patient specific optical devices, we have optimized transparent materials and print process resolution to enable contact lenses and intraocular lenses with smooth surfaces.