Fluorescence-based Artemisinin Sensing Using a Pyronin B-doped Cellulose Film Reconstituted from Ionic Liquid

Abstract

In this work, the first use of a cellulose hydrogel film reconstituted from ionic liquid (IL) 1-butyl-3-methylimidazolium chloride for the fluorescent determination of a plant antimalarial endoperoxide artemisinin is reported. The sensing material was fabricated by noncovalent co-immobilization of the fluorescent cationic dye pyronin B and complex of Mn(II) with anionic surfactant sodium dodecyl sulfate into the film prepared by dissolution and regeneration of microcrystalline cellulose in ionic liquid. Artemisinin determination in a concentration range of 0.25–8 µM is based on the dynamic quenching of pyronin B fluorescence (emission wavelength/excitation wavelength of 581/355 nm) that is accelerated by the above-indicated complex. The developed disposable cellulose film exhibits a high sensitivity toward artemisinin (limit of detection of 30 nM), sufficient selectivity for pharmaceutical analysis, a rapid response time (30 s), and a strong stable fluorescent signal for over a month. The applicability of the cellulose film was demonstrated by analyzing a dietary supplement with an extract from the traditional Chinese herb Artemisia annua. The accuracy of the fluorescent determination of artemisinin in the dietary supplement was supported by a liquid chromatography–mass spectrometry technique. The developed fluorescent cellulose film is a biocompatible and easy to handle sensing material that makes it suitable for wide variety applications in pharmaceutical analysis.