Study on modification of hydroxyapatite/magnesium phosphate bone cement by N-acetyl-l-cysteine

Abstract

Magnesium phosphate cement has good biological activity and degradation performance. However, it still has the defects of poor strength and water resistance. N-acetyl-l-cysteine has good osteogenic properties. The nano-hydroxyapatite/magnesium phosphate cement was modified by N-acetyl-l-cysteine, and the effects of N-acetyl-l-cysteine on the strength, degradation and biological activity of nano-hydroxyapatite/magnesium phosphate cement were studied. The results showed that the compressive strength of 0.5 wt% N-acetyl-l-cysteine modified nano-hydroxyapatite/magnesium phosphate cement could reach 76.1 ± 1.4 MPa after soaking in simulated body fluid for 28 days, which was 6.3% higher than that of the control group (the content of N-acetyl-l-cysteine was 0 wt%), and the softening coefficient of each age was higher than that of the control group. Cell experiments proved that N-acetyl-l-cysteine could effectively promote cell proliferation and improve the expression of osteogenic related genes and proteins. After implanting the composite bone cement into rats’ femurs for 12 weeks, the materials were gradually wrapped and absorbed, and the new bone tissue grew from outside to inside, indicating that N-acetyl-l-cysteine bone cement had an good ability to promote bone formation. Therefore, the composite bone cement of this study has potential application prospects in clinical bone repair.