Controlled release of cobalt ions from polyphosphate glasses

Owing to their tuneable solubility, phosphate glasses are of interest for the controlled release of therapeutic ions. Here, we investigate the release of cobalt ions, which may stimulate blood vessel formation. Substituting cobalt for calcium in soda lime polyphosphate glasses resulted in minor structural changes as shown by IR spectroscopy and molar volume calculation. Cobalt release during immersion increased linearly with substitution, confirming that released amounts can be tuned easily via glass composition.