The release of doxorubicin from submicrometer bovine serum albumin (BSA) microspheres has been quantitated using dynamic dialysis. Mathematical models have been proposed based on zero- or first-order release of drug from solid colloidal matrices. The models also account for the permeability constant of the dialysis membrane. Results obtained by the dynamic dialysis technique resemble those obtained using a conventional dissolution method. The release of doxorubicin from the microspheres can be adequately described by a biphasic zero-order model.
Colloids Delayed-Action Preparations