Basic principles and terms

• PDA View: The PDA Chromatogram window is customizable; up to four views can be displayed at one time (any combination from the following views may be selected: Isoplot, Chromatogram, Spectral, 3D, Peak Purity, Peak Purity Spectra, Spectral Library and Spectral Search). The user can easily extract chromatographic signals from PDA data to determine the optimal detection wavelength for each peak.
• PDA Method: The Clarity PDA method includes an option for spectral library search and peak purity analysis.
• Spectral Library: The Clarity software compares the peak spectra with the spectra of an unlimited number of spectral libraries. Spectra stored in a Spectral Library include retention times and analysis parameters (optional). The Spectral Library Search can perform automatic identification of integrated/calibrated components (peaks). The library search may be constrained by the RT Window and by Wavelength Range. Either the Least Square, the Weighted Least Square or the Correlation Method is used for calculating library search matches. A Background Correction option is also available.
• Peak Purity: This analysis helps to discover hidden impurities. Peak Purity test is applied to all integrated/calibrated peaks in the active signal and is calculated from 5 or all spectra within the peak. The similarity curve is displayed in the PDA Chromatogram window. Peak Purity analysis can be optimized by setting custom preferences relating to wavelength restriction and absorbance threshold.