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Cambridge University Science Magazine
You’ve lost and won countless games of Monopoly, consumed your body weight in turkey sandwiches and selection boxes, and sung along to the last Christmas song on the radio. There’s no getting away from it: Twelfth Night is rapidly approaching, and with it, the annual ritual of stripping the home of its tinsel, wreaths and greetings cards. One question, however, remains- what should be done with the Christmas tree? Well, according to researchers in Allahabad, India, the needles of these festive firs could be used to sterilise nano devices used in medicine.

Bacterial infection at the site of implantation of medical devices remains a major problem in biomedicine, despite improvements in sterilisation techniques. Writing in the International Journal of Nanoscience and Nanotechnology, the team suggest that an extract from the Douglas fir (Pseudotsuga menzietii) may be combined with silver nitrate solution to produce nanoparticles, which can then be dispersed in chitosan polymer and used to coat metals and other materials used in medical procedures.

Silver is known to have bactericidal properties, and the extract from the Douglas fir behaves as a reducing agent, converting the silver ions in the nitrate solution to silver nanoparticles. The silver/chitosan bionanocomposite produced has antimicrobial and sterilising properties that may be able to prevent the transfer of pathogenic microorganisms into tissues via equipment such as prosthetics and sensors. This provides a safe and effective method of coating medical and surgical appliances, hindering microbial growth.

So, while we for now toss the final fallen needles from our Christmas trees atop the compost heap, consider the contribution they may make in the future to the needles found in our operating theatres.

DOI: 10.1504/IJBNN.2012.051217

Written by Mrinalini Dey.