I think the paper is highly cited since it describes a MS approach capable of accurate mass measurement using direct ionization methods to screen active ingredients in pharmaceutical samples without the need for any sample pre-treatment. This technique could be applied to many areas of application which require a rapid turnaround.

“Mass spectrometry offers speed, sensitivity and selectivity over other methods used for chemical analysis.”

The methodology describes how rapid, accurate mass measurements were obtained for the generation of elemental compositions of pharmaceutical samples using direct ionization methods, coupled to an instrument with elevated resolution. The techniques require minimal or no sample pretreatment. These ionization concepts were first introduced by Professor Graham Cooks of Purdue University in 2004.

Rapid ambient sampling methods using direct ionization techniques for detection by mass spectrometry is a type of analysis which has proven to be convenient and also significant for the rapid detection and characterization of explosives, as well as in the discovery of illicit drugs and identification of counterfeit drugs. It also has the potential to be useful in high-throughput assays within the pharmaceutical method development environment.

I was initially inspired by a talk given in 2005 by Prof. Graham Cooks entitled "Desorption Electrospray Ionization (DESI): A New Method of Ionization" at the ASMS Conference in Texas. The ability to rapidly analyze samples in the ambient environment with minimal sample preparation was fascinating.

Within a few days of returning from the meeting I generated my first accurate mass MS and tandem MS results obtained from pharmaceuticals samples and synthetic polymers using direct ionization methods. In other words, I became involved in this research thanks to Prof. Cooks’ stimulating lecture.