Different in vitro and in vivo behaviors between Poly(carboxybetaine methacrylate) and poly(sulfobetaine methacrylate)

Poly(sulfobetaine methacrylate) (pSBMA) and poly(carboxybetaine methacrylate) (pCBMA) are two well-known zwitterionic polymers known for their excellent antifouling properties. In this work, these two zwitterionic polymers were compared both in vitro and in vivo. Both of them exhibited excellent antifouling properties and low macrophage uptake although there were negligible differences in resistance to nonspecific protein adsorption of their hydrogels and cell internalization of their star polymers. However, it is found that the β- Cyclodextrin-CBMA (CD-CBMA) showed a circulation time one order of magnitude longer than CD-SBMA, which implied that small differences in vitro may lead to a dramatic difference in vivo. This work demonstrated that pCBMA showed greater potential than pSBMA in biomedical applications.