High-throughput preparative process utilizing three complementary chromatographic purification technologies.

A high-throughput process was developed in which wells in plates generated from parallel synthesis are automatically channeled to an appropriate purification technique using analytical data as a guide. Samples are directed to either of three fundamentally different preparative techniques: HPLC with UV-triggered fraction collection, supercritical fluid chromatography (SFC) with UV-triggered fraction collection, or HPLC with MS-triggered fraction collection. Automated analysis of the analytical data identifies the product compound mass and creates work lists based on chromatographic properties exhibited in the data so that each preparative instrument cherry picks the appropriate list of samples to purify when a preparative-scale plate is loaded.

Incorporation of an electro-optic ion detector into an improved plasma-source mass spectrograph.

Throughout the history of mass spectrometry, array detectors have been used to conduct simultaneous and continuous mass-spectrographic studies. The benefits of acquiring multichannel data through the use of an array detector are well known and include greater duty cycle, improved precision through ratioing and internal-standardization techniques, and better quantitative analysis of fast signal transients. Because of these benefits, numerous types of array-detector-based instrumentation have been developed, including optical and mass spectrometers. Presented here is the improved performance of a plasma-source Mattauch-Herzog mass spectrograph fitted with a multichannel electro-optic ion detector. A glow-discharge source is used for all measurements. Previously reported array-detector-based data for this mass spectrograph were severely limited in quality and featured extremely poor peak shapes and resolution. Several figures of merit relevant to array detectors will be presented, including sensitivity, resolution, peak shape, and abundance sensitivity, all of which have been significantly improved. Remaining negative aspects of the array-detector performance include susceptibility to a magnetic field and the absence of uniform sensitivity across the array surface.