Integrated Optical Sciences
Biomolecules and nanostructures
The Optical Sciences group studies the interaction of light and matter at the nanoscale.
We do this by exploring ways to shape light and its environment. It's what we call
active and passive control. Our current focus is on the interaction of light with
biomolecules and nanostructures. We are part of Twente
University's Department of Science and Technology and member of the
Genetic applications of single molecular detection
Combined near-field fluorescence and shear force microscopy is applied to image and study genetic material with single molecular cytochemical sensitivity. The combination brings together several advantages: (I) resolution beyond the diffraction limit, while retaining the advantages of multi-colour detection and single molecule sensitivity; (II) complemented with molecular resolution topographical imaging, using shear force feedback, for unambiguous localisation of fluorophores. Thus mapping and co-localisation studies of genetic material are performed at an individual molecular level. The location of maximum fluorescence of the molecule is determined with an accuracy of ~ 1 nm. The in-plane orientation of the molecular dipole is readily determined for all molecules in a single image using polarisation excitation/detection. With the same probe shear force phase feedback is used for topographic imaging of DNA complexes, with 0.2 nm vertical sensitivity. Dynamic environmental effects on nucleotide photophysics will be investigated on single molecular basis.