Ultrasound is a popular choice for imaging inside the body because it can reveal the deep tissue regions that light-based fluorescence techniques cannot reach. But existing ultrasound scattering particles, or ‘contrast agents’, are limited by their large size, poor stability, and the inability to label specific cells. Mikhail Shapiro and colleagues at Caltech in the US have now shown that gas-containing nanostructures generated by micro-organisms to help them float may offer the perfect solution………
http://nanotechweb.org/cws/article/tech/56579
