Images of lambda DNA molecules were obtained by total internal reflection excitation in a capillary.

The DNA molecules labelled with YoYo and covalently bound to the surface of the capillary adopt a coil conformation. When a flow is applied in the capillary, the molecules are stretched to their full length (16 micrometers) and align into the evanescent field.  (See video attached!) 

                                                                       Results obtained by Marcel Reuter and Gerard Giraud