A direct determination of a glucose–arsenic complex by electrospray ionization time of flight mass spectrometry

Abstract

Electrospray ionization time of flight mass spectrometry (ESI-TOF-MS) was used to identify elemental ions from the glucose–arsenic interaction in the aqueous phase. In glucose solution, the most abundant ions were m/z 203, m/z 163, m/z 158, m/z 145 and m/z 115, whereas some additional arsenic bearing ions, m/z 271, m/z 235 and m/z 213 were observed from a glucose–arsenic solution in alkaline pH (≥ 7.5) at 37 °C. The binding was best fitted to 1 : 1 isotherm model and the value of the dissociation constant (K_d) was 39.8 μM. Results suggest that the polyatomic ions derived from glucose interact with the available arsenic ions in blood and form a complex which might play a role in diseases caused by arsenic exposure.