Abstract

Resonance Raman spectroscopy is a powerful technique for probing the vibrations of particular chromophores in multicomponent systems. By tuning the wavelength of the excitation laser into resonance with an electronic absorption band of only one molecular species, the vibrational Raman scattering from this species can be selectively enhanced. Thus, resonance Raman spectroscopy can provide structural information for chromophores in solution or biological chromophores within their functionally active protein environment. However, since the very nature of the experiment requires that the excitation light be absorbed by the sample, the measurement of resonance Raman spectra is often made difficult by a large fluorescence background in the same spectral region as the Raman scattering. The problem of fluorescence interference from intrinsic sample emission is often further exacerbated in biological samples, where low-concentration impurities with large fluorescence yields can be difficult to remove. Even weak fluorescence, with an effective fluorescence quantum yield of ≈10⁻⁴, completely overwhelms resonance Raman signals, which have typical quantum yields of ≈10⁻⁷.

Multi-excitation Raman spectroscopy technique for fluorescence rejection

Scott T. McCain, Rebecca M. Willett, and David J. Brady
Opt. Express 16(15) 10975-10991 (2008)

Shifted-excitation Raman difference spectroscopy for in vitro and in vivo biological samples analysis

Mário Augusto da Silva Martins, Dayana Gonçalves Ribeiro, Edson Aparecido Pereira dos Santos, Airton Abrahão Martin, Adriana Fontes, and Herculano da Silva Martinho
Biomed. Opt. Express 1(2) 617-626 (2010)

Microsystem 671 nm light source for shifted excitation Raman difference spectroscopy

Martin Maiwald, Heinar Schmidt, Bernd Sumpf, Götz Erbert, Heinz-Detlef Kronfeldt, and Günther Tränkle
Appl. Opt. 48(15) 2789-2792 (2009)

Capability of shifted excitation Raman difference spectroscopy under ambient daylight

Martin Maiwald, André Müller, Bernd Sumpf, Götz Erbert, and Günther Tränkle
Appl. Opt. 54(17) 5520-5524 (2015)

Raman spectroscopy: techniques and applications in the life sciences

Dustin W. Shipp, Faris Sinjab, and Ioan Notingher
Adv. Opt. Photon. 9(2) 315-428 (2017)