[Adsorption and sustained release of epirubicin from carbon-coated iron nanocrystals].

Objective: To evaluate the adsorption and desorption of epirubicin (EADM) by carbon-coated iron nanocrystals (CCIN).

Methods: EADM standard curve was generated. After thorough mixture of CCIN and EADM with sonication, the mixture solution was centrifuged at high speed to obtain dissociated EADM for evaluating the adsorption capacity of CCIN. A dialyzer was used to evaluate the desorption of drug-loaded CCIN particles in different media (PBS, normal saline, or distilled water), at different temperatures, and with different quantities of loaded drug.

Results: The adsorption of EADM by CCIN presented linear adsorption before saturation and saturation adsorption, with an adsorption saturation point of about 160 microg/mg. The desorption of EADM from CCIN particles was affected by such factors as the extraction media, temperature, and quantity of the loaded drug. Compared to distilled water, PBS and normal saline improved the release rate of EADM from the drug-loaded CCIN particles. Higher temperature also contributed to higher release rate of EADM. Higher release rate of EADM occurred after the CCIN particles adsorbed greater amount of EADM.

Conclusion: CCIN shows an EADM adsorption pattern of Langmuir isotherm adsorption. Such factors as higher temperature, PBS solution, higher speed of medium replacement, and more drug adsorbed all contribute to a higher release rate of EADM.