Detecting diseases with DNA sensors - Scientists in China have improved the accuracy of DNA sensors for use in disease detection. DNA sensors detect pathogenic and genetic diseases by binding to target DNA strands that are related to the disease and giving a signal that shows how much of the DNA is present. Recent developments in the technology make use of gold nanoparticles functionalised with primer strands that bind to the DNA of interest. When the primers link to the targets, changes in the nanoparticles' UV-visible absorbance provide a quantifiable signal. Ken Cham-Fai Leung from the Chinese University of Hong Kong and coworkers have modified this approach to improve the sensitivity and accuracy.