Indian scientists unearth Assam's Muga silk's wound-healing powers

Moving past its image as a popular textile, Indian scientists have tapped into Assam's durable Muga silk to craft sutures, used for closing wounds, that have the potential for fast and efficient healing.

Muga, popularly known as golden silk due to its glossy texture, is found in select parts of Assam and is a product of the silkworm (Antheraea assamensis), unique to the northeast state. The fibre has the highest tensile strength (ability to withstand stress) among all natural silks and is known for its durability.

Scientists in Assam modified the silk fibre with polypropylene - a versatile substance that is commercially used in making surgical sutures - in addition to applications in packaging, textiles, and housewares, among others. "We grafted polypropylene on Muga (made of silk fibroin protein) by plasma processing (a form of physics) and successfully produced sutures suitable for swift wound-healing. It is the best of all the sutures produced," Joyanti Chutia, emeritus scientist and former director of the Institute of Advanced Study in Science and Technology (IASST), at Guwahati, told IANS on phone.

"The biomaterial was degraded inside the system and wound-healing was observed within a few days," Chutia added. IASST is an autonomous institute under the Indian government's department of science and technology. Wound-healing was observed in rabbits and the study was a collaborative effort between scientists of IASST, Assam Agricultural University and the laser and Plasma Technology Division of Mumbai's Bhabha Atomic Research Centre.

The additions improved the silk fibre's physical and mechanical qualities so much so that the novel material fulfilled the most crucial requirements of ideal sutures for efficient wound-healing, Chutia said. "Because of the processing, the muga silk exhibited good anti-bacterial property (due to enhanced hydrophobic or water-repellent effect) which is one of the most important facets for sutures," she added.

Also, the method used to fabricate these sutures is environment-friendly and non-hazardous, the scientist said. The researchers have applied for a patent this year. Chutia said Muga silk is till now limited to conventional use as clothing material. "Its utility as a potential suture biomaterial remains unexplored, although the possibilities of this silk protein for application in tissue engineering and controlled drug delivery have been reported," she said.The focus is now on furthering the drug delivery aspect of the biomaterial, she said.

Amit K. Dinda, professor in the pathology department at New Delhi's All India Institute of Medicine Sciences (AIIMS), said the new suture material, if it adhered to regulatory norms, could be an important step in developing indigenous materials. "For India, sutures are very important. This will be a good suture material to approach the wound, to close the wound. If this material passes the strict guidelines and can protect from infection, then it could be a very good thing. It also has to be cost-effective since most suture materials are imported," Dinda, president of the Indian Society of Renal and Transplant Pathology, told IANS on the phone.