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Abstract:
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Surfaces with nanopatterned biological functionality are important prerequisites for many applications including developing biosensors , tissue engineering scaffolds and Bio -MEMS devices . This work presents a versatile technique , termed nanoscale orthogonal biofunctionalization imprint lithography , which allows "top -down" highprecision nanopatterning of proteins that can meet the demands of various applications . To show applicability of this technique , it was used to create disposable large scale arrays of nanopatterned cell adhesion proteins for cell culture for the purpose of investigating the influence of nanoscale geometrical parameters on cell -surface interactions . These cell culture arrays were used to systematically vary the size , spacing and density of fibronectin adhesion clusters , which are expected to modulate the signaling induced by the cell adhesion , the clustering of adhesion molecules and the force generated in the cytoskeleton . As a result , it was first determined that the nanopatterned adhesion sites provided an upper limit to the size of a corresponding cell focal adhesion . Cell morphology , actin stress fibers , vinculin distribution , proliferation and motility were all influenced by nanoscale fibronectin island size , and in some cases , the distance between patterns . Several parameters depended biphasically on the pattern size , indicating a very fine regulation of the associated cell signaling . Adhesion area and local stress on the adhesion are modulated by the adhesion size , and the cell response on the nanopattern shows strong parallels to the response on elastic adhesion substrates . In addition , chemical signaling may be influenced directly by changing the activity of associated enzymes . The results of this work build a basis for an understanding of adhesion on the nanoscale level and offer design criteria for the engineering of biomaterials and tissue scaffolds . |