Rapid characterization of alkylpolyphosphonates by CZE with indirect photometric and mass spectrometric detection

Abstract

Methods for the rapid characterization of industrial alkylpolyphosphonates (APPs) by infusion MS and CZE with indirect photometric (IPD) and MS detection are described. Technical-grade APPs, including alkylaminepolyphosphonates with 3-5 phosphonate groups and different hydrocarbon skeletons, hydroxyethyl-amino-bis(methylenephosphonic acid), hydroxyethylidene-diphosphonic acid, and 2-phosphonobutane-1,2,4-tricarboxylic acid, were examined. A 10 mM solution of adenosine triphosphate disodium salt at pH 2.2 was used as BGE. The nominal compounds of the industrial APPs and their impurities were well resolved in less than 15 min. The peaks were identified by using extracted ion electropherograms, which were obtained at the m/z values indicated by the peaks of the infusion spectra. Low concentrations of esters, anhydrides, and APPs having different hydrocarbon skeletons compared to nominal compounds, and lacking phosphonate and methylene-phosphonate groups with respect to them, were found. Also, hydroxyethyl-aminobis(methylenephosphonic acid) contained an intramolecular ester at a concentration close to that of the nominal compound. Application of CZE-IPD and CZE-MS to the quality control of industrial APPs, and of CZE-MS to the identification and characterization of APPs in cleaning products, was demonstrated.

Trace-level determination of phosphonates in liquid and solid phase of wastewater and environmental samples by IC-ESI-MS/MS

“…Phosphonates represent challenging analytes, requiring special analytical methods and treatment [6,[40][41][42][43][44][45]. They possess little chemical reactivity and no chromophoric groups.…”

“…Established separation techniques involve ion pair chromatography (IPC) on reversed phase columns with ion pair reagents [22,40,48] and anion exchange chromatography (IC) [43,49,50]. Detection has been accomplished via photometry after transformation into UVabsorbent metal complexes by pre-column derivatization with iron(III) [22,40,51], ESI-MS [42,48], and phosphorussensitive inductively coupled plasma mass spectrometry (ICP-MS) [43]. The determination from the low to sub μg/L range, as required for the quantification of surface water samples, requires a pre-concentration step.…”