Deep‐Ultraviolet Biomolecular Imaging and Analysis

Abstract

Deep‐ultraviolet light, 200–300 nm in wavelength, interacts with nucleic acids and proteins strongly compared to visible and infrared light. In this article, the interaction between deep‐ultraviolet photons and biomolecules is discussed. Especially, the absorption and autofluorescence of biomolecules by the deep‐ultraviolet excitation are examined. Applications of deep‐ultraviolet absorption and autofluorescence to label‐free biomolecular imaging and analysis of cells and tissues are shown. Resonant Raman scattering at nucleotide bases and aromatic amino acids as another important topic of deep‐ultraviolet photonics is reviewed in biomolecular imaging and analysis. The discussion extends to the recent progress in the development of deep‐ultraviolet microscopes as well as a variety of deep‐ultraviolet optical devices such as light sources, detectors, and objectives. The issue of photodamage due to deep‐ultraviolet irradiation on cells and tissues is also discussed. It has been recently suppressed with use of lanthanide ions. The experimental results of the photodamage suppression are shown. For surface‐enhanced resonant Raman scattering, autofluorescence enhancement, and tip‐enhanced resonant Raman scattering microscopy, plasmonic materials applicable in the deep‐ultraviolet range are discussed.

Zero-mode waveguides can be made better: fluorescence enhancement with rectangular aluminum nanoapertures from the visible to the deep ultraviolet

“…These results nd application in improving the performance of ZMWs for single molecule analysis at high concentrations, and are especially relevant for monitoring fast biomolecular dynamics, 4,5 realizing ultrafast single-photon sources, 14 and for interrogating molecules with ultraviolet plasmonics. [57][58][59][60][61][62] Methods…”

“…Achieving the brightest emission rate together with short uorescence lifetimes is important for applications on fast biomolecular dynamics, 4,5 single-photon sources, 14 and also for the newly-developing eld of ultraviolet plasmonics. [57][58][59][60][61][62] Here we rationally explore the use of rectangular-shaped nanoapertures milled in aluminum to enhance the uorescence emission rate of single molecules from the near infrared (excitation 635 nm, detection 655 to 755 nm) down to the deep ultraviolet (excitation 266 nm, detection 310 to 410 nm). We use aluminum layers with optimized deposition parameters, 63,64 as the response for gold lms falls below 600 nm and hence gold lms cannot be used efficiently for dyes with emission from the green to the ultraviolet.…”

Preferred metabolic pathway of bovine muscle fibre revealed by synchrotron–deep ultraviolet fluorescence imaging

“…This fluorescence emission is mainly due to the autofluorescence of tryptophan. 22,26,27 The contrast variations observed on the fluorescence images do not seem specific to tryptophan because they are observed on the other images, particularly with the bandpass at 412-438 nm and 420-480 nm. The best contrast is observed for Figure 2f at 275/420-480 nm which suggests that some muscle fibres are more fluorescent than others.…”

“…The best contrast is observed for Figure 2f at 275/420-480 nm which suggests that some muscle fibres are more fluorescent than others. The other fluorophores most likely to be involved in the autofluorescence of UV-excited muscle fibres are NADH (260 and 345/400-600 nm) 15,[27][28][29] and pyridoxine (252 and 322/400-550 nm). 15 Their excitation is lower at 275 nm.…”

“…15 The autofluorescence of tyrosine (274/306 nm) cannot be observed under our conditions because there is no filter able to visualise its fluorescence emission. 15,27 Fibre-type identification…”