Hydroxyapatite for use as an animal cell culture substratum obtained by an alternate soaking process

Hydroxyapatite (HAp), the major inorganic component of hard tissues in vivo, was formed in/on a PVA gel. The HAp formation ratio depended on the reaction cycle number, but was independent of the alternate soaking period per cycle. The Ca/P molar ratio of HAp formed at 10 reaction cycles was very close to the theoretical value of HAp, 1.67. CHO-K1 cell adhesion, proliferation and maximum cell density on HAp plates were better on plates formed at two or five reaction cycles using 200 mM CaCl₂ and 120 mM Na₂HPO ₄ solutions than on plates formed under other conditions. Furthermore, the adhesion ratio of CHO-K1 cells on HAp plates formed at 10 reaction cycles was about 60% of those at two or five reaction cycles.