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Can a lab be too capable for its own good? A case study
When our lab acquired Imaging ATR as an FTIR accessory we found we could effectively address many challenges that we had to refuse before.
Reasons for this favorable change? In this it’s good to contrast current technology with some of the reasonable advice which chemistry professors were inclined to give concerning the use of IR/FTIR i.e. something along the lines of “Don’t use it for mixtures”. While this isn’t such bad advice it is out of date and can be overemphasized. We use FTIR almost exclusively for mixtures, rubber is almost always a heterogeneous mixture, and while FTIR isn’t as good as something like GC-MS, e.g. for resolving 30 component mixtures, it is very often more than good enough. What recent advances have changed is that they give FTIR, particularly microscopic imaging ATR the following capabilities (A) resolution on the X,Y plane from the microscope and the Z plane from the ATR crystal, (B) the ability to perform trace enrichment because of this spatial selectivity. (C) the ability to analyze a sample with minimal sample prep: making a solution is not necessary; neither is it required, as with GC-MS, that the sample be volatile. The other thing that even some experienced analytical chemists overlook: there is seldom a need for an exhaustive analysis. If the rubber analyst can characterize the top one or two species then the job is usually done.
One end result of the improved technology: we see and identify things that we missed before. Some of these items are very plausible and from a practical standpoint, very welcome to our requesters. This paper will describe what happened when we repeatedly found convincing evidence for something that seemed very implausible, so that our newfound expertise seemed for a time to undermine the lab’s credibility.