Ionic liquids as mobile phase additives for determination of thiocyanate and iodide by liquid chromatography

Abstract

An analytical method was developed for the simultaneous determination of thiocyanate and iodide by reversed‐phase liquid chromatography with UV detection using imidazolium ionic liquids as mobile phase additives. The chromatographic behaviors of the two anions on a C18 column were studied and compared with four types of reagents including imidazolium ionic liquids, pyridinium ionic liquids, 4‐aminophenol hydrochloride and tetrabutylammonium as mobile phase additives. The effects of the concentrations of imidazolium ionic liquids, organic solvents and detection wavelength on separation and detection of the anions were investigated. The role of ionic liquids, retention rules and mechanisms were discussed. The separation of the anions was performed on the C18 reserved‐phase column using acetonitrile‐0.3 mmol/L 1‐amyl‐3‐methylimidazolium tetrafluoroborate (10:90, v/v) as mobile phase, with column temperature of 35°C, flow rate of 1 mL/min and detection wavelength of 210 nm. Under these conditions, the two anions can be completely separated within 6 min. The limits of detection were 0.05 mg/L. The method was applied for the determination of thiocyanate and iodide in ionic liquid samples and iodide drugs, and the spiked recoveries ranged from 97 to 101%. The method is simple, accurate and meets the requirements of quantitative analysis for thiocyanate and iodide.

Microextraction with smartphone detection of thiocyanate in saliva of tobacco smokers using paper‐based analytical method

“…Several approaches have been reported to determine SCN − levels in different matrices, including spectrophotometry [21,22], spectrofluorimetry [23,24], gas chromatography [25,26], high-performance liquid chromatography (HPLC) [27][28][29], ion chromatography [30,31], amperometry [32,33], voltammetry [34,35], and flowinjection analysis [36]. However, some of these techniques are time-intensive and require pretreatment processes, costly equipment with high detection limits, intricate chemometric analysis, and toxic reagents.…”

The Utilization of Triacontyl-Bonded Silica Coated with Imidazolium Ions for Capillary Ion Chromatographic Determination of Inorganic Anions

“…An IM salt was covalently immobilized on silica particles and used for separation of inorganic and organic anions [39][40][41][42]. IM ionic liquids were also used as the mobile phase additives in reversed phase liquid chromatography for analysis of anions [43][44][45]. In the present study, the preparation of IM-based stationary phases was accomplished by a permanent coating procedure; its simplicity is a distinct advantage over the synthetic methods.…”

Simultaneous separation and indirect ultraviolet detection of chlorate and perchlorate by pyridinium ionic liquids in reversed‐phase liquid chromatography

“…The analytes using ILs as mobile phase additives are mainly organic compounds [24][25][26][27][28][29][30][31][32]. However, there are few reports on the analysis of anions [33,34]. There are no reports on the analysis of chlorate and perchlorate using ILs as mobile phase additives in LC.…”