| 摘要 |
Effluent from a liquid chromatograph (LC) is deposited onto a deposition medium having a deposition surface inert to the LC effluent elevated above and parallel to a planar IR reflective front surface, preferably driven so as to define a continuous sample track in a generally circular, spiral or raster pattern. In the preferred embodiment, the deposition medium is a plate of germanium inert to aqueous and nonaqueous solvents, thicker than the longester IR wavelength of interest and having an undercoating of aluminum. Effluent is preferably deposited in a spiral pattern on the deposition medium in the form of a rotating disk. After collection, the reflection spectra can be interrogated by Fourier transform IR spectroscopy. The same collection technique can be used to collect and mount samples for mass spectrometry. To promote solvent evaporation, the effluent discharge is enveloped by a stream of heated nitrogen, particularly beneficial for reversed phase chromatography. By varying the temperature of the stream as a function of the proportions of solvents of differing volatility, the compatibility of gradient elution with surface deposition techniques is improved.
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