Glycol chitin/PAA hydrogel composite incorporated bio-functionalized PLGA microspheres intended for sustained release of anticancer drug through intratumoral injection.

A novel anti-hepatoma drug release hybrid system is prepared by using poly(acrylic acid) (PAA) and glycol chitin as substrate in combination with Paclitaxel (PTX)-loaded bio-biofunctionalized poly(lactic-co-glycolic acid) (PLGA) micro-particles, which is intended for cancer therapy through intratumoral injection. The rheological behavior of glycol chitin (7 wt%)/PAA illustrates that it has low gelling temperature (i.e. 17 °C at pH 7.56) which ensures that the formulation turns to gel at physiological condition. The gelling time of glycol chitin/PAA is 16 minutes at 25 °C and 3 minutes at 37 °C, which is convenient for doctors to inject the in-situ gel formulations into the tumor location of patient. The drug release behavior reveals that the system can dramatically postpone the drug release. The cell viability test indicates that the micro-particles with drug still have 62% inhibitory effect on hepatoma cells in the fourteenth day after combing with hydrogel. This system is a promising approach for cancer therapy through intratumoral injection of in-situ gel formulations to extend retention time at tumor sites.