Near-field fluorescence imaging

Figure Cl.5.3. Near-field fluorescence image 4.5 p.m square) of single oxazine 720 molecules dispersed on die surface of a PMMA film. Each peak (fwhm 100 nm) is due to a single molecule. The different intensities are due to different molecular orientations and spectra. Reprinted widi pennission from Xie 11221. Copyright 1996 American Chemical Society.

Dunn R C, Holtom G R, Mets L and Xie X S 1994 Near-field fluorescence imaging and fluorescence lifetime measurement of light harvesting complexes in intact photosynthetic membranes J. Chem. Phys. 98 3094-8... 

Fig. 4(A) and (B) depict near-field fluorescence images of these films at low and high surface pressures, respectively. The LE-LC phase coexistence is clearly...

Fig. 4. (A) Near-field fluorescence image of a DPPC monolayer at the air-sucrose solution interface under low surface pressure. (B) Near-field fluorescence image of a DPPC monolayer at the air-sucrose solution interface under high surface pressure. (C) Near-field fluorescence image of a DPPC monolayer at the air-sucrose solution interface under high surface pressure, collected using the optical feedback approach. Reproduced with permission from Ref. [19]. Copyright 1999 Blackwell Publishing.

Hosaka, N., and Sarki, T. 2001. Near-field fluorescence imaging of single molecules with a resolution in the range of 10 nm, / Microsc 202, 362-364. 

Fig. 14 Shear force image (a) and near-field fluorescence image (b) of Ikbp DNA fragments labeled with R6G. The DNA sample consists of one fluorophore per strand, and the emission was accumulated for lOms/pixel. The maximum signed is 240 counts/pixel and background is 40 counts/pixel. Reprinted with permission of [54], copyright (1998) lOP Publishing Ltd...

Betzig, E., Chichester, R.J., Lanni, F., Taylor, D.L. Near-field fluorescence imaging of cytoskeletal actin. Bioimaging 1, 129-135 (1993)... 

Figure Cl.5.4. Comparison of near-field and far-field fluorescence images, spectra and lifetimes for the same set of isolated single molecules of a carbocyanine dye at a PMMA-air interface. Note the much higher resolution of the near-field image. The spectmm and lifetime of the molecule indicated with the arrow were recorded with near-field excitation and with far-field excitation at two different excitation powers. Reproduced with pennission from Trautman and Macklin [125].

Fig. 3. (A) Far-field confocal micrograph (35 pm x 35 pm) of a mica-supported DPPC monolayer showing LE-LC phase coexistence, deposited at a surface pressure of 9mN/m. (B) Atomic force micrograph of the film depicted in (A). Bright features denote topographically higher substructure of the film. (C) Near-held fluorescence image of the him shown in (A). (D) Near-held topology image collected simultaneously with the image depicted in (C). Reproduced with permission from Ref. [18]. Copyright 1998 Biophysical Society.

D. Hu, M. Micic, N. Klymyshyn, Y.D. Suh, H.P. Lu, Correlated topographic and spectroscopic imaging beyond diffraction limit by atomic force microscopy metallic tip-enhanced near-field fluorescence lifetime microscopy. Rev. Sci. Instrum. 74, 3347-3355 (2003)... 

Figure 10. Comparison of near- and far-field fluorescence images, spectra and lifetimes. The nearfield images of the two molecules in the upper left quadrant of the scan field are indicative of V-oriented transition dipoles the far-field images of those two molecules are merely weak. The spectrum and lifetime of the molecule indicated by the arrow were taken simultaneously under (a) near-field and (b) far-field excitation, respectively. The corresponding excitation powers are included in the figure. Adapted from Ref. 18.

Figure Bl.22.11. Near-field scanning optical microscopy fluorescence image of oxazine molecules dispersed on a PMMA film surface. Each protuberance in this three-dimensional plot corresponds to the detection of a single molecule, the different intensities of those features being due to different orientations of the molecules. Sub-diffraction resolution, in this case on the order of a fraction of a micron, can be achieved by the near-field scaiming arrangement. Spectroscopic characterization of each molecule is also possible. (Reprinted with pennission from [82]. Copyright 1996 American Chemical Society.)...

A nano-light-source generated on the metallic nano-tip induces a variety of optical phenomena in a nano-volume. Hence, nano-analysis, nano-identification and nanoimaging are achieved by combining the near-field technique with many kinds of spectroscopy. The use of a metallic nano-tip applied to nanoscale spectroscopy, for example, Raman spectroscopy [9], two-photon fluorescence spectroscopy [13] and infrared absorption spectroscopy [14], was reported in 1999. We have incorporated Raman spectroscopy with tip-enhanced near-field microscopy for the direct observation of molecules. In this section, we will give a brief introduction to Raman spectroscopy and demonstrate our experimental nano-Raman spectroscopy and imaging results. Furthermore, we will describe the improvement of spatial resolution... 

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