Study on the Preparation and Properties of Highly Stable Micelles Sealed by Hydrogen Bonds

Abstract The surface cRGD modified polymeric (PMMA- b -PPEGMA-RGD) micelles were constructed by a combination of two-step atom transfer radical polymerization (ATRP), azide reaction, click reaction, deprotection, self-assembly of amphiphilic polymers, and addition reaction. The self-assembled DOX-loaded micelles had spherical morphology. The average size of DOX-loaded micelles measured by scanning electron microscopy (SEM) and dynamic light scattering (DLS) was less than 200 nm. According to the enhanced permeability and retention (EPR) effect of solid tumors, the micelles should have the passive targeting of tumor tissues. The introduction of cRGD on the micelles surface can not only achieve the active targeting of drug carriers to tumor tissues, but also form the network hydrogen bond between the PEG unit at the hydrophilic end of the micelles and the guanidine group in RGD, to improve the uniformity of the particle size distribution and the stability of drug loading, and also achieve the slow release of drugs. The cytotoxicity of DOX-loaded micelles on SGC7901 cells in vitro indicated that PMMA- b -PPEGMA-RGD micelles could provide the same or more remarkable antitumor activity (at low dose) as DOX. The results showed that PMMA- b -PPEGMA-RGD micelles might have great potential applications in the delivery of hydrophobic anticancer drugs.