Exploiting Fluorescence Spectroscopy To Identify Magnetic Ionic Liquids Suitable for the Isolation of Oligonucleotides

Magnetic ionic liquids (MILs), which incorporate paramagnetic ions, promise to minimize manual user intervention, decrease extraction times, and facilitate rapid recovery of the analyte-enriched extraction solvent. If, however, fluorescence is employed in the downstream analysis of an analyte tagged with a fluorophore, the paramagnetic ion may quench fluorescence by introducing new nonradiative processes. Thus, it is necessary to employ a paramagnetic ion that offers a compromise between possessing a high magnetic moment and not introducing new nonradiative channels. Mn(II), Fe(III), Co(II), and Ni(II) are considered in combination with phosphonium cations and anionic ligands based upon halides or hexafluoroacetylacetonate. Among the possibilities examined, MILs containing Mn(II) provide the best alternative for a model system involving DNA.