采用改良湿法纺丝工艺制备Cu²⁺交联再生丝素蛋白（Cu-RSF）缝合线，检测其理化特性，并评估其促进创面愈合效应及生物安全性。

以再生丝素蛋白为原料，经湿法纺丝技术制备缝合线，以Cu²⁺交联处理。采用扫描电子显微镜（SEM）及傅里叶变换红外光谱（FTIR）观察其微观形貌并分析化学结构；通过单轴拉伸试验优化Cu²⁺交联浓度、机械牵伸比及自螺旋时间等工艺参数；以抑菌圈法、细胞计数试剂盒-8（CCK-8）法及L929成纤维细胞划痕实验分别评价其体外抗菌活性、生物相容性及促细胞迁移能力。取6~8周龄SPF级SD雄性大鼠50只，构建背部皮肤全层切口模型，分为Cu-RSF组和6-0 Mersilk^®组（每组25只），分别以Cu-RSF缝合线和6-0 Mersilk^®缝合线间断缝合。术后3、5、7、10、14 d观察切口愈合情况并取缝合处皮肤组织行苏木精-伊红（HE）染色，术后7、14 d行Masson染色，综合评价Cu-RSF缝合线的促愈合效应；术后14 d取5只Cu-RSF组大鼠及5只正常对照组大鼠心、肝、脾、肺、肾组织行HE染色，评价其生物安全性。

采用1.00%（w/v）Cu²⁺交联、1∶1.6转速比机械牵伸及6 min自螺旋工艺制备的Cu-RSF缝合线，平均直径为（101.92±1.67） μm，最大拉伸强度达674.8 MPa（断裂载荷约6.6 N），β-折叠含量为78.60%±1.15%。体外实验显示，Cu-RSF缝合线对金黄色葡萄球菌和铜绿假单胞菌均具有显著抑菌作用，生物相容性良好；L929成纤维细胞划痕实验表明，Cu-RSF缝合线可显著促进成纤维细胞迁移。体内实验显示，与6-0 Mersilk^®缝合线相比，Cu-RSF缝合线可促进皮肤切口闭合；术后7 d，Cu-RSF组胶原沉积率为68.236%±2.334%，显著高于6-0 Mersilk^®组的37.980%±1.466%（P<0.001）；术后14 d脏器毒性评价显示，Cu-RSF缝合线生物安全性良好。

Cu-RSF缝合线兼具优异的力学性能、抗菌活性及促修复功能，可有效加速术后切口愈合。

To prepare copper ion-crosslinked regenerated silk fibroin （Cu-RSF） sutures using a modified wet-spinning process， characterize their physicochemical properties， and evaluate their wound healing-promoting efficacy and biosafety.

Regenerated silk fibroin was used as the raw material to fabricate sutures via wet-spinning technology， followed by Cu²⁺ crosslinking. Scanning electron microscopy （SEM） and Fourier transform infrared spectroscopy （FTIR） were employed to observe the micro-morphology and analyze the chemical structure. Uniaxial tensile testing was conducted to optimize the Cu²⁺ crosslinking concentration， mechanical draw ratio， and self-twisting time. The agar diffusion method， cell counting kit-8 （CCK-8） assay， and L929 fibroblast scratch assay were performed to evaluate antibacterial activity， biocompatibility， and cell migration-promoting capacity in vitro， respectively. A total of 50 SPF-grade male Sprague-Dawley rats aged 6–8 weeks were enrolled to establish a full-thickness dorsal skin incision model and divided into the Cu-RSF group and the 6-0 Mersilk^® group （25 rats per group）， and the skin incisions were closed with interrupted sutures using Cu-RSF and 6-0 Mersilk^® sutures， respectively. Wound healing was observed and skin tissue at the suture site were harvested on postoperative days 3， 5， 7， 10， and 14 for hematoxylin-eosin （HE） and Masson's staining (on postoperative days 7 and 14) to comprehensively assess the pro-healing effects. On postoperative day 14， tissues from the heart, liver, spleen, lung, and kidney were collected from 5 rats each in the Cu-RSF group and the normal control group, and subjected to HE staining for the evaluation of biological safety.

The Cu-RSF sutures prepared with 1.00%（w/v） Cu²⁺ crosslinking， a 1∶1.6 rotational speed ratio mechanical draw， and 6 min self-twisting exhibited a mean diameter of （101.92±1.67） μm， a maximum tensile strength of 674.8 MPa （the breaking load was approximately 6.6 N）， and a β-sheet content of 78.60%±1.15%. In vitro， the Cu-RSF sutures demonstrated significant antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa， favorable biocompatibility， and markedly promoted fibroblast migration. In vivo， compared with 6-0 Mersilk^® sutures， the Cu-RSF sutures facilitated incision closure. On postoperative day 7， the collagen deposition rate in the Cu-RSF group was 68.236%±2.334%， which was significantly higher than that in the 6-0 Mersilk^® group （37.980%±1.466%）， the difference was statistically significant （P<0.001）. Organ toxicity assessment on postoperative day 14 confirmed favorable biosafety of the Cu-RSF sutures.

Cu-RSF sutures exhibit excellent mechanical properties， antibacterial activity， and pro-repair functions， effectively accelerating postoperative incision healing.