| 摘要 |
A method of detecting the presence, absence or quantity of a dye in a sample in a reaction region is provided. The method comprises providing a dye comprising a ligand ion complex, the lowest unoccupied electron level of the ligand having an energy level such that an electron in the excited electron level of the ion may transfer non radiatively to the lowest unoccupied electron level of the ligand, the complex having a ground state electron level; illuminating the dye with a specified wavelength of radiation to detect the presence, absence or quantity of dye; detecting radiation from the illuminated dye; wherein the electron levels of the complex and the wavelength of the radiation are arranged such that electrons in the ground state are promoted to an excited state by photon absorption and it is energetically favourable for electrons to transfer to the lowest unoccupied electron level of the ligand from the excited electron level of the ion and undergo non-radiative relaxation via a thermally accessible electron level between the ground state electron level of the complex and the excited electron level of the ion to the ground state electron level. The method particularly relates to dyes, for use in Raman spectroscopy and its derivatives SERS and SERRS, which exhibit lower fluorescence and hence lower interference to the Raman signal. |
