RHYS scientific — Science Technology Innovation — Compound ID - Used Laboratory Equipment and New Lab Instrument Supplies, UK

Peak Impurities Revealed

Shown here is a chromatogram obtained under isocratic conditions. It appears to be a simple three component mixture.

Purity checks were made with ultra fast on-the-fly scans on the ascending and descending sides of each peak. Peaks 1 and 2 gave identical spectral scans on each side, but peak 3 gave totally different spectra from its two sides indicating a major impurity producing the scan shown in red. Scans were compared by normalising and overlaying.

Despite the impurity, peak 3 appears visually symmetric and its calculated asymmetry factor was
close to 1.00.

Compound Identification

The identity of the 16 peaks in the chromatogram shown was carried out by comparing the spectra with reference library spectra which had been previously scanned and stored in the spectral library facility of the Adept System 4S used.

The spectrum from the reference library which matched the spectrum of peak 8, is shown and is then superimposed on the scan of peak 8.

Clearly there is a close match and a programmed calculation of the match, or similarity, gave a match index of 996.5.