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be obtained without excessively loading the LC column. Nevertheless, the system was basically a very
efficient and simple fraction collecting device. However, is should be noted that the spectrometer and
collection device could probably be oriented, so that after passing through the coating procedure, as the
disk was rotated it would automatically place the sample in the FTIR optical unit. In this case the time
interval between collection and measurement would be reduced, and the need for the physical transfer
of the plate from one unit to the other eliminated. Under such circumstances the device might be
considered an in-line interface, but it would be a moot argument. In addition the disk could easily be
automated and either rotated continuously at an appropriate speed, or actuated automatically from the
signal produced from the UV detector.

Pentoney and Griffiths [11] examined a number of methods for measuring the spectra from solid
samples distributed on a carrier. They considered six different procedures. These included conventional
transmission (i) and external reflection spectrometry (ii) of the sample deposited on a zinc selenide
plate. They also investigated the reflection adsorption spectrometry (iii) of a sample deposited on a
smooth metallic surface. In addition the diffuse reflection spectrometry was examined where the sample
was deposited on a thin layer of sodium chloride attached to either a metallic (iv) or an infrared
transmitting substrate zinc selenide (v). Finally they also examined spectra taken by diffuse
transmission of samples deposited on zinc selenide. From he results it was concluded that conventional
transmission spectra of samples, situated on a flat infrared window, gave the best compromise between
high sensitivity and the faithful representation of relative band intensities, and adherence to the Beer-
Lambert law.

Somsen et al. [12] described a jet spray assembly as an interface for reversed phase LC/FTIR, which
involved the continuous deposition of the eluent from a narrow bore reversed phase column, onto the
surface of a linearly moving substrate. After deposition, the immobilized chromatogram was analyzed
by linearly moving the substrate under an FT-IR microscope while collecting the spectra. The
arrangement performed as a transport interface where the transport medium was used as a
chromatographic