Controlled Release of Doxorubicin from Doxorubicinγ-Polyglutamic Acid Ionic Complex

Abstract EN

Formation of drug/polymer complexes through ionic interactions has proven to be very effective for the controlled release of drugs.

The stability of such drug/polymer ionic complexes can be greatly influenced by solution pH and ionic strength.

The aim of the current work was to evaluate the potential of γ-polyglutamic acid (γ-PGA) as a carrier for the anticancer drug, Doxorubicin (DOX).

We investigated the formation of ionic complexes between γ-PGA and DOX using scanning electron microscopy, spectroscopy, thermal analysis, and X-ray diffraction.

Our studies demonstrate that DOX specifically interacts with γ-PGA forming random colloidal aggregates and results in almost 100% complexation efficiency.

In vitro drug release studies illustrated that these complexes were relatively stable at neutral pH but dissociates slowly under acidic pH environments, facilitating a pH-triggered release of DOX from the complex.

Hydrolytic degradation of γ-PGA and DOX/γ-PGA complex was also evaluated in physiological buffer.

In conclusion, these studies clearly showed the feasibility of γ-PGA to associate cationic drug such as DOX and that is may serve as a new drug carrier for the controlled release of DOX in malignant tissues.