Polyvinylpyrrolidone-semi-interpenetrating network-polycaprolactone/poly(lactic acid) (PVP-semi-IPNPCL/ PLA) hydrogels were prepared through free radical polymerization of N-vinyl pyrrolidone (NVP) in ethyl acetate solution of PCL and PLA. Three kinds of PVP-semi-IPN-PCL/PLA hydrogels were prepared with the hydrophobic to hydrophilic ratio of 1∶9

3∶7

5∶5

respectively. Carbamazepine-succinic acid (CBZ-SUC) cocrystal was prepared through evaporation method. PVP-semi-IPN-PCL/PLA hydrogels were used as drug vector for CBZ-SUC cocrystal delivery. The CBZ-SUC cocrystal loading and

in vitro

release abilities of PVP-semi-IPN-PCL/PLA hydrogels with different hydrophobic to hydrophilic ratios were studied. CBZ-SUC cocrystal loaded hydrogels were prepared with the drug loading capacity of 17%

19%

21%

encapsulation efficiency of 71%

83%

89%

respectively. The

in vitro

release of CBZ was studied in pH 6.8 PBS solution at 37℃

and the results show that the release profiles of hydrogels loaded CBZ cocrystal were better than those of CBZ cocrystal without hydrogels vector. The 3∶7 hydrogel loaded CBZ cocrystal has the highest cumulative release amount

which reached about 70% when dissolved for 96 h. The results of this study show that PVPsemi- IPN-PCL/PLA hydrogels are capable of loading and control release of CBZ-SUC cocrystal. The combination of pharmaceutical cocrystal and hydrogel drug vector can restrain the solution mediated phase transition of cocrystal

which can be an effective way to improve the dissolution behavior and bioavailability of poorly soluble drugs.