Mass spectral detection of peaks from USP analyses can be problematic due to the high ionic strength, non-volatile mobile phases often used with these methods. When MS is needed, the choices have been fraction collection and solvent exchange prior to a reanalysis, or the development of a separate method using a volatile mobile phase. Both choices incur penalties in time and cost.
The ACQUITY UPLC System with 2D-LC Technology system configured for peak transfer can directly transfer a selected peak from a USP chromatographic method to the ACQUITY QDa Mass Detector for mass spectral analysis with no fraction collection, and no redevelopment of the USP method. Configuring the system for at-column dilution will further ensure the quality and repeatability of the mass spectral data collected from the transferred peak.