The application of an innovative MEMS protein chip in real-time total internal reflection fluorescence microscopy

Single biomolecular detection and real-time motion tracking of an anti-IgG molecule in a microchannel was successfully demonstrated by using total internal reflection fluorescence (TIRF) microscopy. Fluorescence-labeled biomolecules were excited at the transparent near-wall region by the evanescent wave which occurred at the optically index-mismatch interface. The MEMS-based microchannels biochip was also well designed and fabricated to exploit to monitor the motion of a single biomolecule in the near-wall flow layer. The motion of a single anti-IgG molecule has been tracked and analyzed under the speed limit 6 mm/s of image capturing system. The 3D positions of a molecule were also plotted to illustrate the biomolecular trajectory.