+Facile extraction of azide in sartan drugs using magnetized anion-exchange metal-organic frameworks prior to ion chromatography

- A type of magnetized anion-exchange metal-organic framework was synthesized.
- MOF materials were used for the adsorption of azide firstly.
- Combined with IC, the MSPE method offered satisfactory performance for detecting trace azide in sartan drugs.
- Compared with previous methods, this approach offers ease of operation, remarkable sensitivity, satisfactory reproducibility and low cost.

Quaternary amine functionalized metal-organic framework MIL-101(Cr) (MIL-101(Cr)-NMe3) was prepared as the sorbent for the magnetic solid-phase extraction (MSPE) of azide from sartan drugs before ion chromatography determination. Magnetization of MIL-101-NMe3 were achieved concurrently by adding MIL-101-NMe3 and Fe3O4@SiO2 to the sample solution under ultrasonication. The prepared Fe3O4@SiO2/MIL-101-NMe3 gave the adsorption capacity of 37.5 mg g−1. The developed method had a detection limit of 0.24 μg L−1 and quantitation limit of 0.79 μg L−1 for azide. The relative standard deviations for the intra-day retention time and peak area were 0.52% and 0.36% (n = 5), respectively. The developed method was successfully applied for the determination of azide in sartan drugs with the recoveries from 96.5% to 100.5%.