Quantification of biomineralization: an in-vitro tissue culture system and microanalysis of calcium, phosphorus and trace elements by total-reflection X-ray fluorescence.

An in-vitro tissue culture system with folded periostea of 17-day-old fetal chick calvaria was combined with analytical methods to achieve quantification of biomineralization. A scanning electron microscope with an energy-dispersive X-ray detector was applied to show the distribution of calcium, phosphorus and trace elements. Calcium and phosphorus were concentrated in the zone of the mineralized matrix. Strontium was distributed similar to calcium. Zinc was distributed equally in the soft tissue and the mineralized matrix. Total-reflection X-ray fluorescence was used for quantification. Thyroxine in high concentration reduces the calcium content of the samples. One week after incubation magnesiumchloride (1.8 mM) or zincchloride (.1 mM) were found to reduce the calcium content by 38% or 82%, respectively.