Simultaneous separation and determination of Tl(I) and Tl(III) by IC-ICP-OES and IC-ICP-MS

Abstract

A new hyphenated method was developed for the speciation of Tl. In this method, Tl(III) was complexed with DTPA to form a Tl(III)-DTPA anionic complex. Tl(I) did not form a complex with DTPA. The two species were separated simultaneously by means of ion chromatography using a Dionex cation exchange guard column, CG12A, and 15 mmol/l nitric acid as eluant. When ICP-OES was used as detector the detection limits for both species were 0.8 mg/l for an inert V-groove nebuliser and 0.1 mg/l for an ultrasonic nebuliser. No spectral interference was observed but high concentrations of metals such as Fe and Al could lead to broadening of the Tl(I) peak. It was demonstrated that the same chromatographic method can be used with ICP-MS detection. Detection limits were then reduced to 25 ng/l for Tl(I) and 70 ng/l for Tl(III).

Simultaneous separation and determination of thallium in water samples by high‐performance liquid chromatography with inductively coupled plasma mass spectrometry

“…The result was different from what Coetzee et al. reported. Compared with the DTPA‐free group, the addition of DTPA can significantly improve the sensitivity of both Tl species.…”

“…The composition, concentration and the pH of mobile phase in anion HPLC system were some different from the previous reports. The result showed that the addition of DTPA in mobile phase plays a key role in separation of Tl species in both HPLC system, which is significant different from the previous reports . Compared with anion HPLC system, cation HPLC system can complete the separation in a much shorter time and the mobile phase is simpler.…”

“…Several studies analyzing the species of Tl based on the hyphenated techniques have been published . Nolan et al.…”

Identification of complexes involving thallium(I) and thallium(III) with EDTA and DTPA ligands by electrospray ionization mass spectrometry

“…Studies with binary systems, which contained a single type of Tl species and a single ligand, were carried out as preliminary determinations in order to establish the peaks associated with specific complexes in the spectra of more complex systems. The studies were not carried out at acidic pH due to the fact that Tl(I) does not form complexes with EDTA under such conditions . The corresponding peaks are presented in Tables and .…”

“…High‐performance liquid chromatography (HPLC) with electrochemical detection and inductively coupled plasma mass spectrometry (ICP‐MS) are two techniques which are often used for the determination of speciation forms of Tl. Recently, there has been an interest in the use of electrospray ionization mass spectrometry (ESI‐MS) for detection of metal cations because it has several unique advantages.…”