Photoimmobilization of insulin onto polystyrene dishes for protein-free cell culture.

Photoreactive insulin was synthesized by coupling with azidobenzoic acid. The insulin derivative was immobilized onto the wells of polystyrene culture plates by photoir-radiation. The photoimmobilized insulin enhanced the growth of anchorage-dependent cells such as Chinese hamster ovary CHO-K1 and mouse fibroblast STO cells by more than native or azidophenyl-derivatized insulin. A small amount of photoimmobilized insulin (1-10% of the amount of the native or derivatized insulin) enhanced the growth of CHO-K1 and STO cells. In addition, the maximal mitogenic effect of the immobilized insulin was greater than that of native or derivatized insulin. Photoimmobilization could be a universal means of immobilizing growth factors onto the surface of materials devoid of chemical functional groups scaffolding growth factors and providing a new protein-free cell culture system or tissue engineering materials.