A series of core-shell microgels with a poly-(N-isopropylacrylamide) (PNIPAM) core and a poly-(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-co-AA)) shell were synthesized. The shell thickness increases with the increasing feeding of the shell solution. The thermosensitive phase transition behavior of these microgels was studied at pH=3.5. Only one phase transition was observed because the volume phase transition temperature (VPTT) of the core was close to that of the shell. Phenylboronic acid (PBA) groups were introduced by EDC coupling of 3-aminophenylboronic acid with carboxylic acid in the shell of the microgel. Three phase transitions were observed in the PBA-modified core-shell microgels. The first one was attributed to the transition of the shell

while the second and the third transitions reflected a heterogeneous structure of the core which originated from the fast incorporation of the BIS crosslinker during precipitation polymerization. The VPTT difference between the BISrich “core” and the BIS-poor “shell” was enlarged by the coverage of the hydrophobic P(NIPAM-co-AMPBA) shell. The glucose-sensitivity of the PBAmodified core-shell microgels was revealed by their increasing hydrodynamic radii in the presence of glucose

however

the increase in particle size was limited because of the non-glucose-sensitive core. The phase transition behavior of the PBA-modified core-shell microgels in the presence of glucose was also studied. With increasing glucose concentration

the VPTT of the shell increased and approached to that of the core. As a result

the coreshell microgels presented only one transition at high glucose concentrations.