Surface Coating Modified Polyglycolide (PGA) Braided Threads as Potential Thread-embedding Materials

Abstract

Polyglycolic acid (PGA) braided threads offer numerous advantages, including good biocompatibility and biodegradability for the application of acupoint catgut-embedding therapy (ACET). However, the surfaces of PGA threads are relatively smooth and lack some function characteristics in the clinical practice. In this study, four types of PGA braided threads with different strands (n=2, 4, 6 and 8) were fabricated firstly, and then to deposit chitosan molecules on their surfaces. Afterwards, characterizations such surface morphology, swelling, mechanical, antibacterial and cytotoxicity properties of threads were fully explored. The results showed that PGA threads after chitosan coating treatment showed larger weight and diameter changing, and swelling ratio. Mechanical properties (breaking strength, breaking elongation and flexibility) had been greatly improved after coating treatment. As for the biological experiments, modified PGA threads have better cell viability and antibacterial activity comparted to that of unmodified ones. In conclusion, surface coating method warrant further study to develop novel PGA embedding materials with outstanding clinical efficacy.