Resonance hyper‐Raman spectroscopy of deoxythymidine monophosphate

Abstract

A 532 nm‐excited resonance hyper‐Raman (HR) spectrum of deoxythymidine is reported. The 532 nm excitation satisfies the two‐photon resonance condition to the ππ* absorption band of the pyrimidine ring at 250–280 nm, and hence we recorded the resonance HR spectrum with high signal‐to‐noise ratio. The resonance HR spectrum of deoxythymidine is compared with its 266 nm‐excited resonance Raman spectrum. The remarkable similarity between these spectra indicates that the single electronic structure contributes to the resonance effect in each case. The peak assignment is given for the RHR bands by analogy with that for the resonance Raman spectrum. This study offers the fundamental information to study DNA using the HR spectroscopy.

Resonance Hyper-Raman Spectroscopy of Nucleotides and Polynucleotides

“…The pyrimidine moiety of dT and dC has only one π–π* state near 266 nm, and it dominates the resonance enhancement processes. The RHR and UVRR spectral patterns match each other in these cases. , Table shows the peak assignments of dT , and dC …”

“…The resonance of the two electronic states above and below 266 nm 43 explains the different intensity pattern of dG, as seen in dA. On the other hand, the RHR and UVRR spectra are identical for dT (Figure 2b) 25 and dC (Figure 2c). The pyrimidine moiety of dT and dC has only one π−π* state near 266 nm, 39 and it dominates the resonance enhancement processes.…”

“…The RHR and UVRR spectral patterns match each other in these cases. 25,36 Table 1 shows the peak assignments of dT 44,45 and dC. 29 On the basis of the RHR spectra of the four deoxynucleotides, we analyzed the RHR spectra of polynucleotides and DNA that involve the interchain hydrogen bonds and conformation change.…”

“…The spectroscopic setup for the UVRR and HR measurements has been described elsewhere. 25 Excitation source output (at 532 nm) from a Nd:YAG pulsed laser (Coherent Talisker Ultra 355-4) was used. The pulse width and repetition rate were 15 ps and 200 kHz, respectively.…”

Unique non‐resonance hyper‐Raman bands of glucose in phosphate‐buffered saline

“…[8,9] Several reports are available on the application of HR spectroscopy to biomolecules. [10][11][12][13] The experimental setup of the 532 nm-excited HR spectroscopy [10,14] and 266 nm-excited Raman spectroscopy [15] were described elsewhere. The 532 nm-excited Raman spectrum was recorded using the HR spectrometer by replacing the notch filter and grating.…”