(571bf) Characterizing Deposition and Culture Conditions for Optimal Cell Release Kinetics from Smart Polymer

Methods traditionally used to detach cells from surfaces destroy the integrity of the extracellular matrix (ECM). This, in turn, damages proteins and receptors on the cell. Poly(N-isopropyl acrylamide), or pNIPAM, is a smart polymer that has become of great interested in the bioengineering community because it has been investigated as a non-destructive cell release method. Above its lower critical solution temperature (LCST), 32C, the polymer is relatively hydrophobic, allowing cells to grow and proliferate just like they do on tissue culture polystyrene (TCPS). Below the LCST the polymer physically changes, becoming hydrophilic and swelling causing cells to spontaneously release. In this work, we investigate the optimization of pNIPAM films for rapid cell release. The pNIPAM films were deposited using a novel solution deposition method (spNIPAM) as well as plasma deposition (ppNIPAM). Characterization of the pNIPAM substrates was done utilizing traditional surface chemistry techniques (e.g., X-ray photoelectron spectroscopy, XPS; interferometry; and contact angle measurements). Bovine aortic endothelial cells (BAECs) were then seeded onto the coated surfaces and allowed to grow to confluence. At confluence, the media used to culture cells was exchanged for a solution at 4, 25, or 37C to determine which temperature and solution combination demonstrated the most rapid cell release. The cells were then observed using light microscopy and the time needed for 100% cell release was recorded. From these results, we conclude that the fastest, most reliable release of BAECs occurred using 4C serum free media (SFM).