Fig. 5.

Release profiles of DOX from different formulations in PBS at pH 7.4 (a) and pH 6.8 (b). PBS of pH 7.4 was to mimic the body environment and PBS of pH 6.8 was to mimic the slightly acidic environment in tumor. All tests were carried out at 37°C. c AuNP retention in tumor at different times after administration, measured by ICP-AES. d DOX retention in tumor at different times after administration, measured by fluorescence imaging system and spectrofluorophotometer, respectively. “Au + DOX(G)” was for Au-DOX-Gel. “Au + DOX(S)” was for AuNPs solution and DOX solution mixture. “DOX(G)” was for DOX loaded hydrogel. “DOX(S)” was for DOX solution. *p < 0.05, **p < 0.01, statistically significance between Au+DOX(G) and Au+DOX(S)