Electrochemical examination of ability of dsDNA/PAM composites for storing and releasing of doxorubicin.

Composites consisting of ss- and ds-DNA strands and polyacrylamide (PAM) hydrogel have been synthesized. DNA was entrapped non-covalently. The obtained DNA biomaterial exhibited a strong increase in guanine and adenine anodic currents when temperature reached the physiological level. This increase was related to the unique oligonucleotide structural changes in the composite. The structural alterations in the PAM lattices were employed for the release of the drug accumulated in the composite. Doxorubicin (Dox) was selected as the drug; it was accumulated by intercalation to dsDNA and was slowly released from the dsDNA/PAM system by using a minor temperature increase (up to 40÷45 °C) as it is routinely done in hyperthermia. The applied release temperature was either constant or oscillating. The binding strength, the rate of Dox release and the properties of the composite were examined using voltammetry, SEM and ICP-MS.