Metal–Organic Frameworks Incorporated Polycaprolactone Film for Enhanced Corrosion Resistance and Biocompatibility of Mg Alloy

Abstract

Magnesium (Mg) alloys are promising candidates for artificial implants because of their excellent degradability and superior mechanical properties. However, the uncontrolled corrosion hinders their applications. Herein, a composite coating of polycaprolactone (PCL) and copper-based metal–organic framework (MOF) modified with folic acid (FA) was constructed on AZ31 Mg alloy. The modified HKUST-1 was uniformly distributed in the PCL matrix through hydrogen bonds, thus improving the compactness of the coating. Electrochemical tests showed that corrosion resistance was significantly enhanced because the corrosion current density was reduced from 7.18 ± 3.243 × 10–7 to 1.10 ± 0.937 × 10–10 A/cm2. In addition, copper ions were gradually released from the composite coating and promoted the proliferation and differentiation of osteoblastic cells. The current study provides a promising multifunctional coating on Mg-based alloys.