Sriyai Montira, Tasati Jagkrit, Molloy Robert, Meepowpan Puttinan, Somsunan Runglawan, Worajittiphon Patnarin, Daranarong Donraporn, Meerak Jomkwan, Punyodom Winita
Bioplastics Production Laboratory for Medical Applications, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
Center of Excellence in Materials Science and Technology, Chiang Mai University, Chiang Mai 50200, Thailand.
ACS Omega. 2021 Oct 25;6(43):28788-28803. doi: 10.1021/acsomega.1c03569. eCollection 2021 Nov 2.
In this study, a medical-grade poly(l-lactide--ε-caprolactone) (PLC) copolymer with a monomer ratio of l-lactide (L) to ε-caprolactone (C) of 70:30 mol % for use as an absorbable surgical suture was synthesized via ring-opening polymerization (ROP) using a novel soluble liquid tin(II) -butoxide (Sn(OCH)) as an initiator. In fiber fabrication, the process included copolymer melt extrusion with a minimal draw followed by sequential controlled hot-drawing and fixed-annealing steps to obtain oriented semicrystalline fibers with improved mechanical strength. For healing enhancement, the fiber was dip-coated with "levofloxacin" by adding the drug into a solution mixture of acetone, poly(ε-caprolactone) (PCL), and calcium stearate (CaSt) in the ratio of acetone/PCL/CaSt = 100:1% w/v:0.1% w/v. The tensile strength of the coated fiber was found to be increased to ∼400 MPa, which is comparable with that of commercial polydioxanone (PDS II) of a similar size. Finally, the efficiency of the drug-coated fiber regarding its controlled drug release and antimicrobial activity was investigated, and the results showed that the coated fiber was able to release the drug continuously for as long as 30 days. For fiber antimicrobial activity, it was found that a concentration of 1 mg/mL was sufficient to inhibit the growth of (MRSA), O157:H7, and , giving a clear inhibition zone range of 20-24 mm for 90 days. Cytotoxicity testing of the drug-coated fibers showed a %viability of more than 70%, indicating that they were nontoxic.
在本研究中，通过开环聚合（ROP），以新型可溶性液体丁氧基锡（Sn(OCH)）为引发剂，合成了一种用于可吸收手术缝线的医用级聚（L-丙交酯-ε-己内酯）（PLC）共聚物，其L-丙交酯（L）与ε-己内酯（C）的单体比例为70:30摩尔%。在纤维制造过程中，该工艺包括共聚物熔体挤出并进行最小拉伸，随后依次进行可控热拉伸和固定退火步骤，以获得具有改善机械强度的取向半结晶纤维。为了增强愈合效果，通过将药物“左氧氟沙星”加入丙酮、聚（ε-己内酯）（PCL）和硬脂酸钙（CaSt）的溶液混合物中，以丙酮/PCL/CaSt = 100:1% w/v:0.1% w/v的比例对纤维进行浸涂。发现涂覆纤维的拉伸强度提高到约400 MPa，这与类似尺寸的商业聚二氧六环酮（PDS II）相当。最后，研究了药物涂覆纤维在控释药物和抗菌活性方面的效率，结果表明涂覆纤维能够连续释放药物长达30天。对于纤维的抗菌活性，发现浓度为1 mg/mL足以抑制耐甲氧西林金黄色葡萄球菌（MRSA）、大肠杆菌O157:H7和白色念珠菌的生长，在90天内产生的清晰抑菌圈范围为20 - 24 mm。药物涂覆纤维的细胞毒性测试显示存活率超过70%，表明它们无毒。
