Paper Spray Ambient Ionization for Direct Analysis of Complex Samples

Mass spectrometry (MS) is a powerful tool for the analysis of complex mixtures. We have developed a new ambient ionization method, named paper spray, to address the need for rapid methods of direct analysis of complex mixtures without sample preparation. Paper spray is applicable to the analysis of a wide variety of compounds, including small organic compounds, peptides, and proteins. Procedures are developed for analysis of dried biofluid spots with whole blood and urine samples. The combination of sample collection from surfaces and paper spray ionization also enables fast chemical screening at high sensitivity. The combination of paper spray with miniature mass spectrometers offers a powerful impetus to wide application of mass spectrometry in non-laboratory environments.