Influence of pH on Growth of Bone in Tissue Culture. ∗

Abstract

Summary and Conclusions

Seven day chick embryo femurs were grown in tissue culture for 2 weeks at 2 pH levels, i.e., pH 7.0-7.3 and 7.8-8.0. The pH's were maintained by a continuous flow of gas, 4% CO₂ in air for the low level and air minus CO₂ for the high. Our results show that more bone is formed and more calcium is deposited at the low than at the high pH. If a local change in pH is desirable in bone growing in tissue culture then it is in the direction of less rather than more alkalinity. These data are strong evidence against the widespread belief that the local factor in bone growth is a change in pH toward the alkaline.