Thin Layer Chromatography - An MS Hybrid Thin Layer Plate Transport Interface for Peptide-Like Materials 3



(a) Spectrum obtained from the Hybrid Plate

(b) Spectrum obtained from plate by contact plate pressing

Figure 27 Spectra Obtained for 4.5 pmol of Valinomycin from the Hybrid Plate and by Contact Pressing Transfer

After separation, the plate (now acting as a transport system) was transferred to the laser desorption mass spectrometer source and spectra taken in the usual manner. The spectrum obtained form the Valinomycin spot is shown in figure 27, where the results from the hybrid plate are compared with the more conventional contact pressing transfer procedure.


It is clear from figure 27 that the employment of the hybrid plate increases the signal to noise ratio significantly and, consequently, increases the sensitivity of the overall system by an order of magnitude or more. For quantitative work it is clear that an external standard will be necessary and the precision of quantitative assays is not reported. However, the technique offers the possibility of very high sensitivity, specific identification and a reasonably rapid assay.