Biodegradable ion-exchange microspheres, prepared from a prefabricated conjugate of albumin and heparin were investigated as carriers for adriamycin. The ion-exchange microspheres could be loaded with adriamycin giving payloads up to 33% w/w, depending on the heparin content of the conjugate. In vitro adriamycin release depended on the ionic strength of the release medium. In ion containing media, for instance saline, 90% of the drug was released within 45 min, whereas in non-ionic media, such as distilled water, only 30% was released. Drug release profiles could be modelled by combining ion-exchange kinetics and diffusion controlled drug release models.
Cremers, H. F. M., Verrijk, R., Noteborn, H. P. J. M., Kwon, G., Bae, Y. H., Kim, S. W., & Feijen, J. (1994). Adriamycin loading and release characteristics of albumin-heparin conjugate microspheres. Journal of controlled release, 1994(29), 143-155. https://doi.org/10.1016/0168-3659(94)90130-9