PARIS: Scientists in Switzerland and the United States on Sunday
said they had created a "nano-velcro" textile that offers a
swift, sensitive and low-cost way of detecting mercury, a toxic
and accumulative pollutant, in water and fish. The fibres are
made out of gold nanoparticles that are coated with compounds
called hexanethiol and alkanethiol, and bind to charged
particles, also called ions, of heavy metal elements. The more
pollutants that are captured, the more conductive the fibres
become, which means that a sample can be easily measured by
passing an electrical current through it. The technique has been
tested on levels of methyl mercurcy in the waters of Lake
Michigan, off Chicago, and in mosquitofish caught in the
Everglades National Park in Florida. In both cases, the samples
had ultra-low levels of mercury and measurements tallied with
analyses made separately by US environmental watchdogs. Mercury,
a heavy metal that affects the brain and nervous system, occurs
naturally but is a bigger risk as a