RESOLUTION OF THE NONSPECIFIC SPECTRA OF BARBITURATES BY UV-PHOTODIODE ARRAY DETECTION

The procedure described uses a photodiode array detector for die qualitative determination of peak identity. The object was to determine the capability of a photodiode array detector to accurately discriminate among non-specific spectra. Ten barbiturates, all of which possessed highly similar non-specific spectra are analyzed and spectrally compared. This is accomplished by establishing a standard spectrum for each barbiturate sample, then comparing a sample spectrum of each barbiturate to the spectral library and noting the accuracy of the spectral match. In order to confirm the ruggedness of the technique, sample spectra from analyses performed with a different HPLC column and with fresh mobile phase were also compared to the standard spectra. In all ten cases, the photodiode array system accurately matched the sample spectra with the corresponding standard spectra.