Facile scalable one-step wet-spinning of surgical sutures with shape memory function and antibacterial activity for wound healing

Surgical suture is commonly used in clinic due to its action in accelerating the process of wound healing.However,difficultly handling in minimally invasive surgery and bacteria-induced infection usually limit its use in a wide range of applications.Here,we report a facile scalable strategy to fabricate surgical sutures with shape memory function and antibacterial activity for wound healing.Specifically,a shape memory polyurethane(SMPU)with a transition temperature(Ttrans)at 41.3℃was synthesized by adjusting the mole ratio of the hard/soft segment,and then the shape memory surgical sutures containing polyhexamethylene biguanide hydrochloride(PHMB)as a model drug for antibacterial activity were fabricated by a facile scalable one-step wet-spinning approach,in which PHMB was directly dissolved in the coagulation bath that enable its loading into the sutures through the dual diffusion during the phase separation.The prepared sutures were characterized by their morphology,mechanical properties,shape memory,antibacterial activity,as well as biocompatibility before the wound healing capability was tested in a mouse skin suture-wound model.It was demonstrated that the optimized suture is capable of both shape memory function and antibacterial activity,and promote wound healing,suggesting that the facile scalable one-step wet-spinning strategy provides a promising tool to fabricate surgical sutures for wound healing.

Influence of surgical suture properties on the tribological interactions with artificial skin by a capstan experiment approach

Tribological interactions between surgical suture and human tissue play an important role in the stitching process.The purpose of the paper is to understanding the tribological behavior of surgical suture interacting with artificial skin,with respect to surgical suture material and structure,by means of a capstan experiment approach and a contact area model.The results indicated that structure and surface topography of the surgical suture had a pronounced effect on the tribological interactions.The apparent coefficient of friction of vicryl surgical suture was the smallest among the three surgical suture materials.As the sliding velocity increased,or the applied load decreased,the coefficient of friction increased.Furthermore,stick-slip phenomena were observed during the sliding procedure.

Dopamine hydrochloride and carboxymethyl chitosan coatings for multifilament surgical suture and their influence on friction during sliding contact with skin substitute

In order to reduce the damage to tissue and fill the interstices between fibers,multifilament sutures are frequently treated with certain coating materials.The objective of this study was to create and characterize dopamine hydrochloride(DA)and carboxymethyl chitosan(CMCS)coatings on surgical sutures and investigate their effects on the frictional performance of the surgical sutures during sliding through a skin substitute.The effects of the treatment on the physical and chemical characteristics of the surgical sutures were evaluated.The friction force of the surgical sutures during sliding through the skin substitute was experimentally determined using a penetration friction apparatus.The coefficient of friction(COF)was calculated using a linear elastic model and was used to estimate the frictional behavior of the surgical suture‐skin interactions.The results showed that the DA coating could evenly deposit on the surface of the etched multifilament surgical suture surfaces in a weakly alkaline buffer solution.The CMCS coating material could form a uniform film on the surface of the sutures.Minor changes in the surface roughness of the multifilament surgical sutures with different treatments occurred in this study.The friction force and the COF of the multifilament surgical sutures with DA and CMCS coating showed little change when compared with untreated multifilament surgical sutures.

Effect of retension sutures on abdominal pressure after abdominal surgery

To evaluate the effect of retention sutures on abdominal pressure and postoperative prognosis in abdominal surgery patients. Methods： This prospective cohort study included patients who were admitted to Daping Hospital from May 15, 2014 to October 11, 2014. A total of 57 patients were enrolled, including 18 patients in the ＂U＂ type retention suture group, 17 patients in the intermittent retention suture group, and 22 patients in non-retention suture group. The demographic data, clinical data and risk factors for abdominal wound dehiscence were recorded. The bladder pressure （IVP） was monitored preoperatively, intraoperatively, and four days postoperatively. Additionally, the incidence of abdominal wound dehiscence and infection 14 days after the operation was recorded. Results： During the operation, the IVP decreased and then increased; it was at its lowest I h after the start of the operation （5.3 mmHg _＋ 3.2 mmHg） and peaked after tension-reducing （8.8 mmHg _＋ 4.0 mmHg）. The IVP values in the ＂U＂ type retention suture group and intermittent retention suture group were higher than in the non-retention suture group 4 days after operation （p 〈 0.005）. The Visual Analogue Scale （VAS） pain scores were 3.9 ~ 2.2, 3.8 ~ 2.0, and 3.0 _＋ 1,0 in the retention suture group, intermittent retention suture group and non-retention suture group, respectively. The VAS pain scores in the ＂U＂ type tension-reducing group and intermittent tension-reducing group were higher than in the non-tension-reducing group （p 〈 0,005）. Conclusion： Although retention sutures may reduce the incidence of postoperative wound dehiscence in abdominal surgery patients, they can increase the IVP and postoperative pain.