Negative ions of dicarboxylic acids observed by plasma chromatography and atmospheric pressure ionization mass spectrometry

Analysis of sulfophthalimide and some of its derivatives by liquid chromatography-electrospray ionization tandem mass spectrometry

A system was developed for the separation of sulfophthalimide (SPI), sulfophthalamide (SPAM), sulfophthalamic acid (SPAA) and sulfophthalic acid (SPA) by ion-pair liquid chromatography and their detection by electrospray ionization tandem mass spectrometry (ESI-MS-MS). Except for SPAM, the 3- and 4-sulfo-isomers of the analytes were separated by HPLC using volatile tributylamine as ion-pairing agent. Initial fragmentations of the analytes in the negative mode involve losses of CO2 or HNCO or condensation via H2O or NH3 elimination. ortho-Effects of the sulfonate group were recognized in the fragmentation of the respective 3-sulfo-isomers and allowed us to assign the order of elution of the SPAA isomers. Quantitative analysis of these sulfonated aromatic compounds with MRM detection was elaborated and resulted in detection limits ranging from 1 pg for SPA to 13 pg for SPAA isomers and in limits of quantification of 2-10 microg/L for 5 microL volumes of injected tap water, municipal wastewater or industrial effluents up to salt contents of 0.5-1 g/L. The method was applied to study the isomer-specific chemical and microbial transformations of SPI, which was previously shown to be formed by white-rot fungi from sulfophthalocyanine textile dyes.

Table of reduced mobility values from ambient pressure ion mobility spectrometry

This review presents a list of reduced ion mobilities that have been measured under ambient pressure conditions and reported in the open literature during the 16-year period of 1970-1985. Ions reported are listed in order of increasing reduced mobility along with the name of the parent compound, the reduced mobility of additional product ions observed in the spectrum, the carrier and drift gases, the temperature of the drift region and the reference where the data were reported. Also, ions that have been identified by mass spectrometry are indicated with an asterisk.