Melting curve analysis in a snapshot

The thermal denaturation of molecules is an essential method in biochemistry and diagnostics, including the measurement of single nucleotide polymorphisms and the binding analysis of proteins. We present a method for the all-optical high speed measurement of melting curves. A thin sheet of water is locally heated with an infrared laser to obtain a spatial temperature distribution between 20 and 100 degrees C. Using a fluorescence microscope a melting curve is recorded within 50 ms. This is about 10 000-times faster than state-of-the-art fluorometry and yields the same results for the validation example of a DNA hairpin. (c) 2007 American Institute of Physics.