Differential Staining of Cartilage and Bone in Fetal Mouse Skeleton by Alcian Blue and Alizarin Red S

Abstract

Full-term mouse fetuses were fixed in 95% ethanol, skinned and eviscerated. The specimens were stained with 70% ethanol containing 0.015% alcian blue, 0.005% alizarin red S and 5% acetic acid at 37℃ for 2-3 days. After washing in water, the specimens were put in 1% aqueous KOH until skeletons were visible through surrounding tissue. Then the specimens were cleared through 20% aqueous glycerin containing I% KOH, 50% glycerin and 80% glycerin, and stored in 100% glycerin. Cartilage was stained blue and ossified skeleton was stained red.