High resolution imaging of patterned model biological membranes by localized surface plasmon microscopy.

We report on microscopic imaging of phospholipid membranes. To achieve nonlabel, noncontact, and high spatial resolution imaging of the membranes, we use optically excited localized surface plasmons as a virtual measurement probe to obtain the local refractive index. This enables significantly higher lateral resolution of approximately 170 nm. We reveal that the developed microscope has the capability of observing lipid bilayers with thickness of 3.0 nm deposited into the gaps in a patterned lipid bilayer with thickness of 4.6 nm. We find that the thickness resolution against the deposited lipid bilayer is approximately 0.33 nm.