Optical microscopy as a means to identify graphene is hampered by the low absorptivity of its monolayers and few-layer
structures. However for many of the upcoming applications for graphene, it is essential to develop techniques to readily
deliver images of graphene based structures. We report on two novel techniques and additionally on a well-known, but
modified technique for the identification of graphene. All of the described methods employ standard optical reflection
and transmission microsocopy and can be readily adapted in most laboratories. One of the novel techniques is based on
the enhancement of the optical contrast by refractive index matching using oil immersion microscopy. The second
technique, microdroplet condensation, exploits the hydrophobicity difference between the carbonic sheets and almost
any arbitrary substrate. The third technique is a modification of the already well known technique to enhance the
visibility contrast of graphene using interferometric effects by employing a Si wafer coated with a dielectric of specific
thickness.
We describe a novel label-free method to analyse protein interactions on microarrays as well as in solution. By this
technique the time resolved native protein fluorescence in the UV is probed. The method is based on alterations of the
protein upon ligand binding, and, as a consequence, of alterations of the environment of the proteins' aromatic amino
acids. These amino acids act as internal probes, and as a result, the fluorescence lifetime of the proteins change due to
binding to a ligand partner such as another protein. We were able to demonstrate the feasibility of the method with many
compounds, including protein-protein, protein-antibody, protein-nucleic acid and protein-small ligand pairs. Unlike
to many other label-free techniques, the sensitivity of the method does not depend on the size of the counterbinding
ligand and therefore is particularly suitable for drug monitoring, when small molecules are involved.
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