This study introduces a new approach for producing highly monosized polymer
microcapsules. The technique employs an impressive process in which the so
lute, dissolved freely in a solvent, is diffused uniformly into the preexis
ting monosized polymer particles in the form of a fine emulsion. The solven
t is then eliminated, resulting consequently in solute-loaded polymer micro
capsules. We named it a solute co-diffusion method, SCM. The loading effici
ency of the solute was predicted successfully by a thermodynamic equation.
In the experiment, the indomethacin-loaded poly(methyl methacrylate) microp
articles were produced via SCM. From our results, SCM is expected to expand
significantly the drug-loading technology in related fields.