Sub-wavelength size fluorescent particles attach to specific gene sites or a magnetic bead that is maneuvered around a cell volume to produce evanescent fields when illuminated in the far-field from light outside the cell volume. Light scattering from the sub-wavelength particles produces near-field interactions with surrounding molecules. The sub-wavelength scattering particles may be metallic spheres. Using particles within the cell removes large far-field scattered light from the mechanical structure of a supporting probe. Near-field light is modulated with an oscillating magnetic field, and micro-positioning is accomplished by a computer controlled DC magnetic field to scan the particle around within the cell. The Near-Field Intra-Cellular Apertureless Microscope (NICAM) technique enables non-destructive sub-wavelength resolution imaging without inserting a near-field (illumination or collection mode) probe into a cell.
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