Invited Paper BI1-WeM9
Nanofabrication of a Novel Cell Array on Ultrathin Hydrophilic Polymer Gels Utilizing Electron Beam Irradiation and UV Excimer Laser Ablation
Many methods for surface patterning presented to date are based on lithography techniques and microfabrication onto silicon or glass substrates. Here, we show a novel method to prepare patterned surfaces on polystyrene substrates by grafting ultrathin cell-repellent polymer layers utilizing both electron beam (EB) polymerization and local laser ablation techniques for microfabrication. Polyacrylamide(PAAm) was grafted onto tissue culture polystyrene (TCPS) dishes using electron beam irradiation. Water contact angles for these PAAm-grafted TCPS (PAAm-TCPS) surfaces were less than 10° with grafted amounts of PAAm of 1.6 mg/cm@super 2@ as determined by FT-IR/ATR method. UV excimer laser (ArF: 193 nm) ablation resulted in the successful fabrication of micropatterned surfaces by exposure of the basal polystyrene layers. Many cell types adhered only to the ablated domains after pretreatment of the patterned surfaces with optimized concentration of fibronectin solution. The ablated domain sizes have significant influence on the number of cells occupying each domain. Cell patterning functionality of the patterned surfaces was maintained for more than 2 months without losing pattern fidelity. Utilization of these surface fabrication techniques are also presented for basic cell biology as well as preparation of cell-based biosensors.