Pseudo target release behavior of simvastatin through pH-responsive polymer based on dynamic imine bonds: Promotes rapid proliferation of osteoblasts

Abstract

In this article, a simvastatin loaded pentaerythritol tetra(3-mercaptopropionate)-allylurea-poly(ethylene glycol) (SIM-loaded PETMP-AU-PEG) polymer with excellent biocompatibility by means of in-situ loading method was synthesized. The presence of the imine bonds has given the polymer system an excellent response performance to weak acidic environment. Specifically, for the SIM-loaded polymer, the simvastatin cumulative release dose is only 2.2% in the first 2 h, and the first 32 h of the cumulative release dose is less than 10% in pH 7.4; However, in pH 6.0, the first 2 h of the cumulative release dose is 65.2%, and the first 32 h of the cumulative release dose is almost 100%. MC3T3-E1 osteoblast cell culture experiments show that the SIM-loaded polymer at pH 6.0 can accelerate the proliferation of osteoblasts significantly, which is expected to promote the rapid proliferation of bone cells in clinical applications and accelerate the healing of the lesion region.

Keywords: Controlled release; Simvastatin; Stimuli-responsive polymer; pH-responsive polymer.