MW triggered fraction collection

The development of the first HPLC system with MW-triggered fraction collection was described by Zeng et al. [50] at CombiChem. This system was a dual analytical-preparative instrument with parallel-column format, termed parallel Analyl/PrepLCMS." developed by the modification of commercially available instrumentation. This system had software-controlled valves that applied sample to each path from a single autosampler and had the capacity to purify and analyze more than 100 samples per day. Initial analytical LC-MS data acquired by the system allowed the identification of samples that require... 

All of the aforementioned HPLC purification systems employ detectors other than mass spectrometers as the selection criteria by which peaks are collected. With these systems, however, mass spectrometry is generally employed as a primary structural validation tool. More recently, systems have been described whereby a mass spectrometer has been added to preparative HPLC format to detect compounds of interest for collection. A recent review by Kassel [9] discusses the relative merits of employing MW-triggered versus UV-triggered fraction collection in various environments for the purification of combinatorial libraries. 

Figure 11.6. (A) Purification example 3. (B) Reaction and product depicted in chromatogram of the MW-triggered HPLC purification. Chromatography conditions C8 column (21.2 x 50mm, 5-p, Luna" Combi-HTS, Phenominex), 10-100% aqueous 0.1% TFA/MeOH (0.5 minute hold, 5.5 minute gradient, 1 minute hold) at 40mL/min over 8 minutes. Fraction collection triggered by positive ion ESI-MS. Arrow indicates desired reaction product.

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