A quick diagnostic test for NMR receiver gain compression.

Modern NMR spectrometers require receivers to work within their linear ranges to maintain high fidelity line shape and peak integration. For better sensitivity, the receiver gain has to be optimized to detect dilute analytes; however, gain compression needs to be avoided. Here, we explore if and how linear receiver performance can be achieved for a couple of representative gain settings on a spectrometer. In the case of slight receiver gain compression, not only will the peak integral be attenuated but a very small line-shape change can also be observed. Hence, we can resort to resonance integration and line-shape analysis for gain compression diagnosis. As such, NMR signals, regardless of their observed amplitude difference in frequency domain, can be accurately compared in quantitative analysis. 2010 John Wiley & Sons, Ltd.