Adhesion, growth and detachment of cells on modified polystyrene surface.

By adsorbing poly(N-isopropylacrylamide) (PNIPAAm) from an aqueous solution onto oxidised polystyrene without the need for grafting the polymer to the surface, we showed here that cells(CHO-K1) adhere and grow well at 37 degrees C and are detached by lowering the temperature to 10 degrees C without any other deleterious treatment. Both bacterial culture grade polystyrene Petri dishes and polystyrene beads (120 to 250mum diameters) commercially available used in static conditions of growth were tested with similar results. The contact angle of modified Petri dishes with a water droplet increases from 36 to 58 degrees when the temperature is raised from 25 to 37 degrees C indicating change in hydrophilicity of the surface as a function of temperature.