Assessing the environmental ruggedness of paper spray ionization (PSI) coupled to a portable mass spectrometer operated under field conditions.

Significant efforts have went towards coupling portable mass spectrometric systems and ambient ionization methods, with a culminating goal of field-based, point-of-need screening of harmful chemicals. While fieldable, ambient MS methods are an intriguing combination, ruggedness of these ionization methods in regard to naturally-occurring environmental conditions while operating in-situ , such as ambient temperature, relative humidity (RH) and wind, bears further investigation, as such reports are limited. In this work, a systematic characterization of paper spray ionization-mass spectrometry (PSI-MS) performance under variable environmental conditions was undertaken on a field-deployable MS system. Of all conditions, the presence of wind speeds greater than 3 m/s (∼7 MPH) was shown to have the most substantial effect on the spectral attributes of signal intensity and duration of the PSI-MS spraying event. Generally, moderate ambient temperature and %RH produced the best spectral performance for PSI-MS. Heat maps were generated from field-collected data across variable temperature and %RH in an effort to inform general PSI-MS performance trends and guide on-site operation by potential users. [Display omitted] • The environmental ruggedness of PSI-MS operating in the field was evaluated. • Performance attributes were shown susceptible to moderate wind speeds. • Performance was best at moderate ambient temperature and high relative humidity. • No appreciable effect on false negative rate was observed at extreme temperatures. • Data is presented to inform and guide potential field operators and SOP generation. [ABSTRACT FROM AUTHOR]