An electric field enhanced by a metallic nanoprobe has locally induced coherent anti-Stokes Raman scattering (CARS) of adenine molecules in nanometric DNA network structure. Owing to the third-order nonlinearity, excitation CARS polarization is extremely confined end tip apex, resulting spatial resolution far beyond diffraction limit light. Our tip-enhanced microscope visualized structure at specific vibrational frequency (approximately 1337 cm(-1)) corresponding ring-breathing mode diazole...

Kinesin-1, the founding member of kinesin superfamily proteins, is known to use only a subset microtubules for transport in living cells. This biased proposed as guidance cue polarized neurons, but underlying mechanisms are still poorly understood. Here, we report that kinesin-1 binding changes microtubule lattice and promotes further binding. high-affinity state requires nucleotide-free state. Microtubules return initial low-affinity by washing out or non-hydrolyzable ATP analogue AMPPNP...

Heterogeneity is a critical determinant for multicellular pattern formation. Although the importance of microscale and macroscale heterogeneity at single-cell whole-system levels, respectively, has been well accepted, presence functions mesoscale heterogeneity, such as cell clusters with distinct properties, have poorly recognized. We investigated biological in signal-relaying abilities (excitability) self-organization spiral waves intercellular communications by studying self-organized...

We present a near-field Raman investigation in the subnanometric vicinity of metallic nanotip, where tip-sample distance is precisely controlled by our newly developed time-gated illumination technique. Using this scheme on an isolated carbon nanotube, we have profiled spatial decay evanescent light. also investigated extremely short-ranged chemical and mechanical interactions between metal tip apex molecules adenine sample, which are observable only within tip. The results show with...

We report on the experimental identification of Raman modes that are enhanced through chemical effect in surface spectroscopy 4-aminothiophenol (also known as p-mercaptoaniline) adsorbed gold substrate. Introduction a thin spacer layer between metal and sample can prevent any possible bonding atoms molecules, hence such shows only those electromagnetic effect. Alternatively, significant increase could be observed presence halide ions compared to their absence. This result provides another...

System level understanding of the cell requires detailed description state, which is often characterized by expression levels proteins. However, state comprehensive information cell, usually obtained from a large number cells and their disruption. In this study, we used Raman spectroscopy, can report changes in without introducing any label, as non-invasive method with single capability. Significant differences spectra were observed at both cytosol nucleus different cell-lines mouse,...

To be able to predict antibiotic resistance in bacteria from fast label-free microscopic observations would benefit a broad range of applications the biological and biomedical fields. Here, we demonstrate utility Raman spectroscopy monitoring type mode action acquired bacterial population Escherichia coli, absence antibiotics. Our findings are reproducible. Moreover, identified spectral regions that best predicted modes explored whether signatures could linked genetic basis resistance....

The acquired immune system, mainly composed of T and B lymphocytes, plays a key role in protecting the host from infection. It is important technically challenging to identify cell types their activation status living intact cells, without staining or killing cells. Using Raman spectroscopy, we succeeded discriminating between cells visualized labeling. Although spectra were similar, they could be distinguished by discriminant analysis principal components. activated with anti-CD3 anti-CD28...

Temporal fluctuations of spectral shapes have been observed in tip-enhanced Raman scattering (TERS) spectra adenine molecules. The TERS a nanocrystalline cluster molecules showed distinct temporal changes including peak frequencies and intensities extraordinary enhancements several peaks. fluctuating signals originate primarily from the first layer 5 nm thick cluster. possible origin is attributed to molecular orientation under metal-coated tip, which responsible for changing adsorption...

Abstract Since the carrier mobility in a strained silicon thin layer is enhanced compared to unstrained layers, finding tremendous attention as promising material for ultralarge integrated electronic circuits assembled on one substrate. These substrates, however, suffer from nanoscale fluctuation of strain distribution, which can strongly affect performance devices. Raman spectroscopy powerful tool because optical phonons spectra are influenced by strain. However, efficiency extremely small...

Abstract The spatial resolution in optical imaging is restricted by so‐called diffraction limit, which prevents it to be better than about half of the wavelength probing light. Tip‐enhanced Raman spectroscopy (TERS), based on SPP‐induced plasmonic enhancement and confinement light near a metallic nanostructure, can however, overcome this barrier produce images far beyond limit. Here article, basic phenomenon involved TERS reviewed, high achieved through technique discussed. Further, shown...

Abstract Fluorescent proteins have been widely used in biology because of their compatibility and varied applications living specimens. are often undesirably sensitive to intracellular conditions such as pH ion concentration, generating considerable issues at times. However, harnessing these intrinsic sensitivities can help develop functional probes. In this study, we found that the fluorescence yellow fluorescent protein (YFP) depends on concentration solution dependence be enhanced by...

In many phenomena of biological systems, not a majority, but minority cells act on the entire multicellular system causing drastic changes in properties. To understand mechanisms underlying such phenomena, it is essential to observe spatiotemporal dynamics huge population at sub-cellular resolution, which difficult with conventional tools as microscopy and flow cytometry. Here, we describe an imaging named AMATERAS that enables optical over-one-centimeter field-of-view a-few-micrometer...

We established a volumetric trans-scale imaging system with an ultra-large field-of-view (FOV) that enables simultaneous observation of millions cellular dynamics in centimeter-wide three-dimensional (3D) tissues and embryos. Using custom-made giant lens magnification ×2 numerical aperture (NA) 0.25, CMOS camera more than 100 megapixels, we built scope AMATERAS-2, realized fluorescence transverse spatial resolution approximately 1.1 µm across FOV 1.5×1.0 cm 2 . The 3D resolving capability...

On the basis of mechanism surface enhanced Raman scattering, it is shown that coherent anti-Stokes scattering (CARS) molecules attached to isolated gold nanoparticles are strongly and signal from each particle well localized. In addition well-known advantages CARS, CARS combined with a scanning system metallic nanoprobe tip can realize high spatial resolution microscopy beyond diffraction limit light by locally enhancing weak signals small sample volume. This concept realized tip-enhanced...

The authors developed a tip-enhanced near field Raman microscope that can precisely regulate longitudinal distance between metallic tip and sample molecules. This was done by employing time-gated photoncounting scheme enabled us to observe exponentially decaying intensity with the tip-sample distance. exponential decay shows characteristic of enhanced generated localization surface plasmon polaritons apex. applied evaluate metal-coated tips also investigate confinement at gap two metal...

A tip-enhanced Raman scattering (TERS) microscope has been developed, which is based on the tapping-mode operation of atomic force microscopy. By synchronizing a multichannel detector with tapping oscillation metallic nanotip, one can measure tip-sample separation dependent TERS spectrum and dynamically obtain both near- far-field signals during periodic tip. This facilitates imaging in situ point-by-point removal background, resulting higher contrast imaging. Furthermore, we an extremely...

Abstract We observed local enhancement of coherent anti‐Stokes Raman scattering (CARS) by isolated gold nanoparticles. CARS signals from adenine molecules a DNA base attached to nanoparticles were strongly enhanced owing the electromagnetic at proximity particles. The localization was successfully microscope using collinear configuration tightly focused lasers. spectrum factor 2000 and in good agreement with measured spontaneous spectrum. Copyright © 2003 John Wiley & Sons, Ltd.

A tip-enhanced electric field at a metallic probe tip of apertureless near-field scanning optical microscope was applied to third-order nonlinear process, coherent anti-Stokes Raman spectroscopy. The combination the enhanced and nonlinearity resolved molecular vibrations adenine molecules embedded in deoxyribonucleic acid double-helix nanocrystals beyond diffraction limit light.

Nanoscaled variation in crystalline properties was demonstrated through tip-enhanced Raman scattering (TERS) for a thin GaN sample, which apparently showed good and uniform at microscale conventional micro-Raman scattering. The observation attributed to the field enhancement super-resolution associated with near-field technique. factor of TERS intensity assessed be larger than 2.8×104. Variations were observed spatial resolution beyond diffraction limit probing light. authors propose an...