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Calcium hydroxyapatite (HA) is the primary mineral component of bones and teeth. It can be found in rocks as well as in sea coral.  Solid HA is coated onto titanium, titanium alloys, or stainless steel and used to make bone implants.  HA may also be used in a spreadable paste form to repair bone.  This material forms a porous surface onto which tissue may adhere and grow.  The chemical structure of HA is that of a hydrated calcium phosphate.

We frequently test both HA raw material and finished implants for Ca/P ratio as well as many impurities.  NIST supplies a certified Standard Reference Material SRM 2910 upon which some of these test methods have been validated. The methods we use are summarized below.  These methods are the same or similar to the methods used by NIST to certify their SRM.  For more information on these methods, click on the links below or review the literature references listed in the SRM certificate.

Calcium Hydroxyapatite (HA)
 Ca10(PO4)6(OH)2

Bone growth around HA

For a quotation on testing HA ...

Testing Calcium Hydroxyapatite (HA)

Tests per WCAS Methods

% Calcium (Ca) by EDTA titration, similar to USP assay
% Phosphorus (P) by an ascorbic acid colorimetric method
Lead (Pb) for CA Prop 65 by isotope dilution - ICPMS
>60 Element Screen for impurities by ICPMS
As, Hg, Cd, etc. by ICPMS
% Ca, P, and Ca/P Ratio by X-Ray Fluorescence (XRF)
Hydrocarbon Contamination (implants) by FTIR

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Formerly West Coast Analytical Service (WCAS) and Bodycote Testing Group