Membrane potential around single molecules has been measured by using the nonlinear optical phenomenon of second harmonic generation. This advance results from the interaction between a highly dipolar molecule with a selectively directed highly polarizable 1-nm gold particle. With this approach, a second harmonic signal, which is enhanced by the nanoparticle, is detected from a volume of nanometric dimensions. This present work clearly shows that functional cellular imaging around single molecules is possible by selectively directing an antibody with a 1-nm gold label to a specific membrane protein. The results of this work open the way for three- dimensional, high resolution functional imaging of membrane electrophysiology in cells and cellular networks.
|Original language||American English|
|Number of pages||5|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - 8 Jun 1999|