We will report on the first direct monitoring of the dynamics of live cells using a non contact scanning near field optical microscopy (SNOM) [1]. We used SNOM to examine rhythmically beating cardiac myocites in culture [2]. Scans could be halted at any point to record localized contraction profiles. We found that contractions show subnanometric high vertical sensitivity and changed shape dramatically within adjacent sub micron-sized areas. We believe that the spatial dependency of contractions arises because of the SNOM's ability to resolve the behaviour of individual sub-membrane actin bundles. Our results, combining imaging and real time recording in localized areas, reveal a new, non invasive method for studying the dynamics of live biological samples.
References
1. Betzig E., Trautman J.K., Harris T.D., Welner J.S., Kostelak R.J., Breaking the diffraction barrier: optical microscopy on a nanometric scale. Science 251, 5000, 1468-1470.
2. Shrier A., Clay J.R., Pacemaker currents in check embryonic heart cells change with development, Nature 283 748, 670-671, 1980.