The automatic visualisation of carry-over in high-throughput flow injection analysis mass spectrometry

A high-throughput flow injection analysis mass spectrometry system (FIA-MS) was developed for the purity estimation of multiple parallel combinatorial chemistry synthetic samples, and has measured over 70 000 samples in two years. An in-house Visual Basic application called RackViewer allows a fast, direct, easy and economic inspection of the estimates at geographically dispersed laboratory workbenches via the corporate network. Due to the large numbers of samples involved, surreptitious inter-sample carry-over represents one threat to the accuracy of these purity estimates. It can become serious when reducing the measurement duty cycle in order to develop faster throughput rates. Over 400 samples drawn equally from five different combinatorial synthetic families were measured to explore this threat. By analogy with the colour rendering of the purity estimates, inter-sample carry-over was automatically calculated for each measurement, colour rendered and then depicted within RackViewer. Our FIA-MS in daily use has a median basal carry-over of 0.88%. (C) 1999 Elsevier Science B.V. All rights reserved.