CUSAT research team invented for X-ray visible antibacterial biodegradable surgical suture for which the patent is pending. The research was done by Sneha K. Ramanathan under the supervision of Dr Sailaja G.S.
The suture is developed from natural cellulosic fibres extracted from Agave Sisalana plant leaves by controlled surface treatments (mercerization and bleaching) and a facile coating technique. Surgical sutures are biomedical implants used for wound closure by tissue approximation and ligation of blood vessels during the wound healing process.
Sutures comprise filament, fibres or thread-like biomaterials which can be absorbable or non-absorbable by nature. The surgical sutures demand certain characteristic features such as good biocompatibility, preferential absorption, adequate mechanical performance and tensile strength, good handling features, knot security, degradation profile etc.
There is a possibility that sutures could be a source of infection and also could trigger the development of biofilms around the wound. Modern suture materials demand not only chemical and biological properties but also enhanced bioactivity and controlled degradation. But the sutures presently available cannot be monitored through non-invasive methods.
A flexible, non-metallic surgical suture with intrinsic X-ray visibility with controlled biodegradation and excellent antibacterial property has been developed by CUSAT scientists from natural cellulosic fibres extracted from Agave Sisalana plant leaves by controlled surface treatments (mercerization and bleaching) and a facile coating technique.
This judicious configuration would be exemplary to facilitate effortless tracking and precise monitoring of the sutured surgical site by diverse X-ray assisted imaging modalities and simultaneously serves as a complementary tool for monitoring the fate of the suture material during the post-operative course. This mechanically empowered suture exhibited an admirable straight-pull tensile strength and a contrast enhancement of 154 % in the digital X-ray radiographic image which is validated further by Micro-CT analysis.
This is accomplished by a customized coating of Strontium oxide integrated Polylactic acid, a clinically relevant biodegradable polymer. Further, the suture has a controlled hydrolytic degradation favourable for long-term suture application (28 days). The surface texture is designed to have a microporous architecture that enabled the loading of antibiotics (typical example Ciprofloxacin) deep inside the pores transforming it into an antimicrobial suture that prevents possible bacterial infections at the surgical site.
The antibiotic release is slow and sustainable (24 % at 28 days) ensuring long-term antimicrobial activity. The major highlights of the suture are its intrinsic radio opacity that facilitates X-ray visibility by non-invasive imaging, feasibility to be used as a marker material during wound healing that enables continuous monitoring and also facilitate identifying the exact position through CT imaging. The controlled degradation accompanied by slow antibiotic release makes it apt for surgical procedures.