Abstract

Enhancing the Hemocompatibility of 3D-Printable Silicone Elastomers for Artificial Lung Applications

Riya Aggarwal, First Author, University of Michigan - Ann Arbor

Our high-resolution PDMS resin for stereolithography was modified by: 1) adding 1% 2-Methacryloyloxyethyl phosphorylcholine (MPC) to the base resin; 2) adding 1.8% Poly(ethylene glycol) methacrylate (PEGMA) to the base resin; or 3) infusing the neat PDMS devices with 2% dimethylsiloxane-[60-70% ethylene oxide] (PEG-PDMS) in ethanol post-printing. Biomimetic microfluidic capillary devices were printed, cleared of uncured resin, then tested for coagulation with freshly-drawn ovine whole blood. Devices (n = 12 per group) were exposed to blood for 10 minutes at 0.8 mL/min (shear of 0.771 Pa) then evaluated for clotting via fluorescent confocal microscopy and clotting area analyses. Statistical significance was determined via a single factor Anova and one-sided unequal t-test. Clotting area analysis determined a 42.5%, 58.3%, and 65.2% decrease between negative control resin (FTD NanoClear) and 1% MPC, 1.8% PEGMA, and 2% PEG-PDMS infusion respectively and a 11.4%, 49.1%, and 57.5% decrease relative to the unmodified PDMS resin. Cell deposition quantified by fluorescent intensity showed a 54.2%, 69.2%, and 88.3% decrease compared to FTD NanoClear and a 40.1%, 59.7%, and 84.6% decrease compared to the unmodified PDMS base resin for the 1% MPC resin, 1.8% PEGMA resin, and 2% PEG-PDMS infusion respectively. All results were statistically significant.