Enzyme-etching technique to fabricate micropatterns.pdf

ORIGINAL RESEARCH PAPER Enzyme-etching technique to fabricate micropatterns of aligned collagen fibrils Honghai Liu ? Ruikai Chen ? Huaxiao Yang ? Wan Qin ? Thomas K. Borg ? Delphine Dean ? Meifeng Xu ? Bruce Z. Gao Received: 3 October 2013 / Accepted: 14 January 2014 / Published online: 23 February 2014  Springer Science+Business Media Dordrecht 2014 Abstract A technique to tailor-make pre-coated, pre-aligned bovine collagen fibrils, derived from neonatal cardiomyocytes, on the surface of a glass slide into a designated pattern is reported. The unwanted collagen-coated area was erased by a collagenase solution and the tailored area was retained by attaching a microfabricated polydimethylsiloxane stamp directly to the collagen-coated surface. Using this technique, collagen patterns with designated orientations and with clear pattern boundaries and defined shapes were fabricated. Keywords Collagen fibrils  Enzyme etching  Microfabrication  Micropattern  Myofibrils  Neonatal cardiomyocytes Introduction The extracellular environment is crucial to the distri- bution of cytoskeletal and cellular functions. Many surface-modification techniques have been developed to direct cell attachment and the cytoskeleton for in vitro study of cell functions. For example, a cytoskeletal arrangement has been controlled by setting the boundaries of the coated extracellular matrix (ECM) components through surface patterning (Bray et al. 2008) or by regulating the fibril config- urations on the surface (Lee et al. 2006). Microcontact printing (lCP) (Chen et al. 1997; Singhvi et al. 1994) and protein alignment (Lee et al. 2006; Simpson et al. 1994) are the two major techniques developed to accomplish extracellular environment modifications. In the conventional lCP method, proteins are first coated on polydimethylsiloxane (PDMS) stamps and then transferred to the target surface (Kane et al. 1999). The lCP technique can be used to create designated boundaries for the coated ECM compo-