Development and characteristics of novel polyglycolic acid (PGA) monofilaments for acupoint catgut-embedding therapy applications

Abstract

Acupoint catgut-embedding therapy (ACET) is considered one of the most promising technologies to replace traditional acupuncture therapy in clinical settings. Polyglycolic acid (PGA) monofilament shows great potential for ACET applications due to its advantages of good formability and biodegradability. The ideal embedding materials are required to have excellent swelling, mechanical, and antibacterial properties. For this paper we prepared two types of PGA monofilaments by first using the melt-spinning method and then applying chitosan onto the PGA monofilaments at three different concentrations. The effects of chitosan coating on the characteristics such as surface morphology, swelling, mechanical, FT-IR, antibacterial, and degradable properties of monofilaments were explored. The results show that chitosan layers and fragments were distributed uniformly on the surface of PGA monofilaments. The expansion rate of samples increased with the concentration of the chitosan coat, and samples 1-PGA 3% (98.32 ± 4.24%) and 2-PGA 3% (123.05 ± 2.87%) exhibited the best swelling behavior. Mechanical properties of PGA monofilaments were greatly improved after chitosan coating. There were few interactions between PGA monofilaments and chitosan molecules according to the FT-IR analysis. Antibacterial efficacy and cytocompatibility of PGA monofilaments were greatly enhanced by the chitosan coating treatment. The degradation time was delayed due to the protective function of the chitosan layers, producing a more lasting effect in the treatment process. In conclusion, the novel PGA embedding monofilaments were successfully developed and a chitosan coating concentration of 3% was chosen as the optimum parameter.

Ultrasonic modification of polylactic acid and polyglycolic acid acupoint catgut embedding monofilaments for juvenile pseudomyopia

“…Among them, the absorption bands at 1436.8 and 1149.4 cm À1 confirmed the presence of -CH 2 and -CH 2 -COO-. 32 Moreover, the modified PGA group (UMPGA1 and UMPGA2) exhibited a new sharp peak at 3515.6 cm À1 , which may be caused by a hydroxyl dimer. These findings could be explained according to inner changes in the molecular structures of chemical bonds caused by the ultrasound modification.…”

A Review on Melt-Spun Biodegradable Fibers

“…Malafeev et al [177] produced absorbable sutures with 91 MPa strength via spinning of PLGA with 10% GA comonomer through a DSM microextruder within a 1 mm diameter die. Fu et al [178] selected PGA to make a monofilament for Acupoint catgut-embedding therapy due to its good formability and biodegradability. They also applied 1-3% chitosan via dip-coating on PGA monofilaments.…”

Surface modification of polylactic acid and poly (D, L-lactide-co-glycolide) biodegradable materials via chitosan-coating treatment: A new approach for developing novel antibacterial acupoint catgut embedding materials

“…27 As shown in our previous reports, chitosan-coating modification can be used to improve the surface roughness, mechanical properties, and biocompatibility of PLA-and PGA-embedding monofilaments. 28,29 Moreover, there are many applications of chitosan in the surface modification of textile materials for different purposes, including salt-free neutral dyeing of cotton, 30,31 antibacterial cotton and wool, 32 dyeing of wool, 33 and antibacterial wound dressings. 34 In recent years, applying chitosan coating on the surface of biodegradable material has become of interest.…”