Yong Yang1, Yubing Xie1, Xihai Kang2, L. James Lee3, and Douglas A. Kniss4. (1) Nanoscale Science and Engineering Center for Affordable Nanoengineering of Polymeric Biomedical Devices, The Ohio State University, 1381 Kinnear Road, Suite 100, Columbus, OH 43212, (2) Obstetrics and Gynecology, The Ohio State University, 1654 Upham Dr., Means Hall 5th Floor, Columbus, OH 43210, (3) Chemical and Biomolecular Engineering, The Ohio State University, Room 125A, Koffolt Labs., 140 W. 19th Ave., Columbus, OH 43210, (4) Department of Obstetrics & Gynecology, College of Medicine & Public Health, The Ohio State University, Columbus, OH 43210
Using low-pressure carbon dioxide (CO2), we demonstrated a novel and universal approach to assembling polymeric micro/nanostructures in an aqueous environment in the presence of cells and biomolecules. By regulating CO2 pressure, the assembly can be completed at biologically permissive temperatures. The original structures are well preserved and the CO2 pressure has little effects on the bioactivity/viability and functionalities of the proteins, DNAs, and cells studied. This method highlights the ability to integrate multiple cell-scaffold constructs into a tissue complex by first allowing the individual cell types to grow on biodegradable polymeric scaffolds and then assembling the desired multiple cell-scaffolds into a 3-D construct. This novel method has the potential to develop fully functional tissue substitutes and provides for a manufacturing platform that thus far has been lacking in the field of tissue engineering. This CO2-assisted bio-assembly method offers an affordable and biologically permissive process, particularly for the simultaneous assembly of a large number of micro/nanostructures containing temperature- and/or solvent-sensitive biomolecules and cells. It opens a new avenue for tissue engineering, cell therapy, drug delivery and cell-based biochips.