Does your cotton shirt stink when you perspire' Researchers at the Indian Institute of Technology, Delhi, may have a new way to stem that foul smell using an extract from a commonly found plant. Treating the fabric with the extract of Quercus infectoria (maju or Aleppo oak) — a plant used in traditional medical systems like Ayurveda and Siddha — can offer an easier and safer way to keep cotton clothes free from disease- or odour-causing bacteria. The study, published recently in the Indian Journal of Fibre and Textile Research, showed that a 12 per cent solution of the tannin-rich extract inhibits bacterial growth up to 90 per cent if used along with alum and copper sulphate. The scientists claim that this bioactive textile, which retained its anti-bacterial quality up to five launderings, could find good use as hospital clothes too.
A researcher from the Tata Institute of Fundamental Research in Mumbai along with his associates in Germany and Spain has designed an extremely narrow photo-detector that can quickly detect hazardous biological and chemical agents in air. Every material exhibits a specific optical fingerprint and this can be detected by analysing the light scattered by it. But to do this, the photo-detectors must have an extremely narrow bandwidth range. The device created by Sandip Ghosh and others has a bandwidth range of six-nanometres. In order to simultaneously detect as many substances as possible, a large number of photo-detectors with very narrow bandwidths is necessary, with each of them sensitive to a particular wavelength. The device presented by the international research team is as small as a pinhead and detects only Ultra-violet radiation of 360 nm. The report appeared recently in the journal of Applied Physics Letters.