Multifunctional Zwitterionic Nanogels for Targeted Drug Delivery and Renal Clearance

Zwitterionic polymers have been shown the excellent ability to prepare non-fouling surface and stealth nanoparticles. Poly(carboxybetaine methacrylate) (pCBMA) is one important type of zwitterionic polymer, beside the non-fouling properties, it can also be easily functionalized, so it is an ideal type of material to develop long circulating nano-carriers for targeted drug delivery. In this work, degradable pCBMA nanogels were prepared, the nanogels could load different imaging reagents and model drugs by suitable methods. In vitro studies show the nanogels poccess extraordinary stability in different environment including saline solutions or undiluted blood serum, and they have very low interaction with immune cells. After conjugated with a targeting ligand, the cell uptake of the nanogels was greatly increased, but their stealth properties were not compromised. By using the degradable crosslinker, the nanogels can be degradable at certain situation, rendering the simultaneous release of the loaded model drug and the disassembling of the nanogels. The degraded products could be removed from the body via renal clearance. The above results suggest the pCBMA nanogels could be an ideal and safe platform for targeted drug delivery.