Manufacturing and physical characterization of absorbable oxidized regenerated cellulose braided surgical sutures

Suture is an important part of surgical operation, and closure of the wound associated with this procedure continuous to be a challenge in postoperative care. Currently, oxidized regenerated cellulose (ORC) is widely used in the absorption of hemostatic materials. However, there is no ORC medical suture product in the market. The objective of this article was to prepare novel braided sutures by TEMPO-mediated oxidation regenerated cellulose (TORC) to achieve a suturable material with biodegradability and ideal mechanical properties. Regenerated cellulose (RC) strands were made into sutures on a circular braiding machine, and TEMPO-mediated oxidation treatment was introduced alternatively after braiding. The RC sutures under different oxidation time were characterized by ATR-FTIR, electrical conductivity, XRD analysis, physical properties and in vitro degradation property. We further demonstrate that the RC sutures were oxidized and formed the carboxylic (-COOH) functional group. With the extension of oxidation duration, the carboxyl content in TORC sutures increased gradually from 5.1 to 10.4% and the strength, weight, and diameter of TORC sutures decreased gradually. Moreover, we proved that the knot-pull strength of TORC-45 declined by 77.8% after 28 days, thus this sutures fulfilled U.S. Pharmacopeia requirement of knot-pull strength. We have shown that TEMPO oxidation reaction significantly promoted the degradation of TORC sutures. Overall, TORC sutures were successfully produced with favorable biodegradability, revealing potential prospects of clinical applications.