A new type of poly(ethylene oxide) (PEO) chain transfer reagent was synthesized and used to mediate the reversible addition fragmentation chain transfer (RAFT) polymerization of 3-(acrylamino)phenylboronic acid (AAPBA) to get three types of PAAPBA-b-PEO-b-PAABPA triblock copolymers with different PAAPBA lengths.The gelation of these copolymers at physiological pH was examined.It was found that hydrogel formation was dependent on the PAABPA block chain length

when the block was too long

no stable gel can be obtained due to the high hydrophobicity of the PAABPA segment.The effects of temperature

polymer concentration and glucose on the rheological properties of the gel were investigated in detail.The results indicated that the formed hydrogels possess solid-like behavior

at high polymer concentrations

gels with high strength and high phase transfer temperature could be obtained.In the presence of high concentration of glucose

interaction of glucose with the PAAPBA block can lead to the increase of the hydrophilicity of the PAAPBA block

thus leading to the break of the hydrogel network with time and finally the gel dissolved in about 1.5 h.Finally

the hydrogels could load FITC-BSA in the hydrophilic regions

and the release profile of FITC-BSA was accelerated in the presence of glucose.