Nanosensors...

Semiconductor nanorods will help monitor neural activities in the future. Courtesy: Y Kuo and S Sasaki / University of California, Los Angeles

Topics: Biology, Modern Physics, Nanotechnology, Semiconductor Technology

Researchers in the US have developed nanosensors that can be directly inserted into a cell’s lipid membrane and be used to measure membrane potential. The devices, which are based on inorganic semiconductor nanoparticles, could potentially record action potentials from multiple neurons as well as electrical signals on the nanoscale – for example, across just one synapse.

Thanks to recent advances in inorganic colloidal synthesis, researchers can now make functional semiconductor nanoparticles whose size, shape and composition can be precisely controlled. Such nanoparticles can be used in applications as diverse as optoelectronics, biological imaging, sensing, catalysis and energy harvesting.

These nanomaterials can also be combined with biological cells to make highly sophisticated hybrid nanomaterials that outperform their purely biological counterparts. Until now, however, incorporating these particles into cell membranes has proved difficult. This is because they are often too big and have surface properties that can lead to non-specific binding on cell membranes. What is more, inserting nanoparticles into membrane bilayers is further complicated by the fact that their surfaces need to be functionalized so that the particles are inserted in the correct orientation.

Semiconductor nanosensor measures membrane potential, Belle Dumé, Nanotechweb.org