Hydrophobic Magnetic Ionic Liquids Research Articles

Neat and rapid preparation of hydrophobic magnetic ionic liquids composed of transition metal chelates featuring in situ formation capabilities in aqueous matrices

Nitrogen and oxygen-donor ligands comprised of alkylimidazoles, tertiary amides, and diglycolamides were employed to form transition metal chelates in the preparation of twelve magnetic ionic liquids. Viscosities as low as 198 cP were achieved.

Sequence-specific eDNA extraction using hydrophobic magnetic ionic liquids attached with oligonucleotide strand

Isolation of high-purity nucleic acids, especially sequence-specific DNA, from complex samples is critical to the downstream nucleic acid analysis. In this work, an oligonucleotide strand-attached magnetic ionic liquid (OSMIL) was designed and prepared for DNA extraction. The attached oligonucleotide strand has a sequence complementary to that of a specific DNA to be extracted. The OSMIL has good hydrophobicity and magnetic response properties. At the extraction temperature, OSMIL was in a liquid state, which was favorable for maximizing the adsorption of DNA; while at the separation temperature, OSMIL was in a solid state (with an average particle size of 897 nm) and could be attracted by an external magnet in 3s, which was favorable for the separation and recovery of DNA. The sequence-specific DNA extraction process with OSMIL is simple and fast. After extraction, the DNA-enriched OSMILs were quickly attracted and separated by an external magnetic field. The extracted DNA was evaluated by a NanoDrop (wavelength detection at 260–280 nm) and the OSMIL can be recycled and reused. The enrichment factor was 0.81. Through single-factor experimental analysis, the effects of OSMIL extraction volume, thermal excitation temperature, thermal excitation time, pH, and other factors on the DNA extraction process were systematically investigated. The RSD of repeatability experiment was 1.19% (n = 3), showing the method has good repeatability. The extraction method presented here has been shown to extract DNA with specific sequences from mixtures containing DNA of different sequences and from mixtures containing proteins, respectively. In addition, the OSMIL has been applied to extract target environmental DNA with specific sequences from different water environments with high extraction efficiency. In the long run, OSMIL has great potential for identifying existing organisms in environmental samples or exploring unknown organisms.

Simple and efficient isolation of plant genomic DNA using magnetic ionic liquids

BackgroundPlant DNA isolation and purification is a time-consuming and laborious process relative to epithelial and viral DNA sample preparation due to the cell wall. The lysis of plant cells to free intracellular DNA normally requires high temperatures, chemical surfactants, and mechanical separation of plant tissue prior to a DNA purification step. Traditional DNA purification methods also do not aid themselves towards fieldwork due to the numerous chemical and bulky equipment requirements.ResultsIn this study, intact plant tissue was coated by hydrophobic magnetic ionic liquids (MILs) and ionic liquids (ILs) and allowed to incubate under static conditions or dispersed in a suspension buffer to facilitate cell disruption and DNA extraction. The DNA-enriched MIL or IL was successfully integrated into the qPCR buffer without inhibiting the reaction. The two aforementioned advantages of ILs and MILs allow plant DNA sample preparation to occur in one minute or less without the aid of elevated temperatures or chemical surfactants that typically inhibit enzymatic amplification methods. MIL or IL-coated plant tissue could be successfully integrated into a qPCR assay without the need for custom enzymes or manual DNA isolation/purification steps that are required for conventional methods.ConclusionsThe limited amount of equipment, chemicals, and time required to disrupt plant cells while simultaneously extracting DNA using MILs makes the described procedure ideal for fieldwork and lab work in low resource environments.

Magnetic ionic liquids as microRNA extraction solvents and additives for the exponential amplification reaction

The detection of microRNAs (miRNAs) from highly complex matrices has become an area of immense interest as their characterization in biological samples has been utilized for disease diagnosis and body fluid identification. However, conventional northern blotting miRNA detection lacks the sensitivity required to detect circulating miRNAs. Additionally, polymerase chain reaction-based methods for miRNA detection require modified oligonucleotides that are difficult to design. Exponential amplification reaction (EXPAR) is an isothermal amplification method used for miRNA detection that is simple to design but suffers from non-specific amplification that masks low concentration miRNAs. Previous studies have shown that magnetic ionic liquids (MILs) are a promising alternative to traditional nucleic acid extraction methods capable of preconcentrating DNA from complex matrices. In this study, three hydrophobic magnetic ionic liquids (MILs) were investigated as EXPAR additives and miRNA extraction solvents. The addition of MIL to the EXPAR buffer decreased the background signal from non-specific amplification and increased the reaction rate. Reactions containing MIL could detect miRNA at concentration levels down to 10 aM. In comparison, reactions that did not contain MIL could not discriminate 10 fM lethal-7a (let-7a) standards from the no trigger control (NTC). All three MILs extracted miRNA from 2-fold diluted plasma, artificial urine, and artificial saliva with only a 1 min dispersion step. By integrating the miRNA-enriched MIL into the EXPAR buffer, the extraction and detection of femtomolar concentrations of miRNA required only 10 min. In contrast, conventional spin column kits require at least 20 min to isolate miRNA, indicating that a dispersive MIL-based extraction is ideal for high throughput analysis of miRNA.

Selective extraction of low-abundance BRAF V600E mutation from plasma, urine, and sputum using ion-tagged oligonucleotides and magnetic ionic liquids.

Sequence-specific DNA extractions have the potential to improve the detection of low-abundance mutations from complex matrices, making them ideal for circulating tumor DNA analysis during the early stages of cancer. Ion-tagged oligonucleotides (ITOs) are oligonucleotides modified with an allylimidazolium salt via thiolene click chemistry. The allylimidazolium-based tag allows the ITO-DNA duplex to be selectively captured by a hydrophobic magnetic ionic liquid (MIL). In this study, the selectivity of the ITO-MIL method was examined by extracting low abundance of the BRAF V600E mutation-a common single-nucleotide polymorphism associated with several different cancers-from diluted human plasma, artificial urine, and diluted artificial sputum. Quantitative polymerase chain reaction (qPCR) was not able to distinguish a 9% BRAF V600E standard (50fg·μL-1 BRAF V600E, 500fg·μL-1 wild-type BRAF) from the 100% wild-type BRAF (50fg·μL-1) standard. However, introducing the ITO-MIL extraction prior to qPCR allowed for samples consisting of 0.1% BRAF V600E (50fg·μL-1 V600E BRAF, 50,000fg·μL-1 wild-type BRAF) to be distinguished from the 100% wild-type BRAF standard. Ion-tagged oligonucleotides (ITOs) are combined with magnetic ionic liquids (MILs) to extract low-abundance BRAF V600E mutation from diluted human plasma, artificial urine, and diluted artificial sputum. The ITO-MIL extraction prior to qPCR allowed for samples consisting of 0.1% BRAF V600E to be distinguished from the 100% wild-type BRAF standard.

Simultaneous cell lysis and DNA extraction from whole blood using magnetic ionic liquids.

Conventional DNA sample preparation methods involve tedious sample handling steps that require numerous inhibitors of the polymerase chain reaction (PCR) and instrumentation to implement. These disadvantages limit the applicability of conventional cell lysis and DNA extraction methods in high-throughput applications, particularly in forensics and clinical laboratories. To overcome these drawbacks, a series of nine hydrophobic magnetic ionic liquids (MILs) previously shown to preconcentrate DNA were explored as cell lysis reagents. The MILs were found to lyse white blood cells from whole blood, 2-fold diluted blood, and dry blood samples while simultaneously extracting human genomic DNA. The identity of metal ion incorporated within the MIL appears to cause hemolysis while the cationic component further reduces the cell's integrity. Over 500pg of human genomic DNA was isolated from 50μL of whole blood using the trioctylbenzylammonium tris(hexafluoroacetylaceto)nickelate(II) ([N8,8,8,Bz+][Ni(hfacac)3-]) MIL, and 800pg DNA was isolated from a dry blood samples using the trihexyl(tetradecyl)phosphonium tris(phenyltrifluoroacetylaceto)nickelate(II) ([P6,6,6,14+][Ni(Phfacac)3-]) MIL following a 1-min vortex step. A rapid, one-step cell lysis and DNA extraction from blood is ideal for settings that seek high-throughput analysis while minimizing the potential for contamination.Graphical abstract.

Magnetic Ionic Liquids as Solvents for RNA Extraction and Preservation.

Ribonucleic acid (RNA) is particularly sensitive to enzymatic degradation by endonucleases prior to sample analysis. In-field preservation has been a challenge for RNA sample preparation. Very recently, hydrophobic magnetic ionic liquids (MIL) have shown significant promise in the area of RNA extraction. In this study, MILs were synthesized and employed as solvents for the extraction and preservation of RNA in aqueous solution. RNA samples obtained from yeast cells were extracted and preserved by the trihexyl(tetradecyl) phosphonium tris(hexafluoroacetylaceto)cobaltate(II) ([P66614+][Co(hfacac)3–]) and trihexyl(tetradecyl) phosphonium tris(phenyltrifluoroacetylaceto)cobaltate(II) ([P66614+][Co(Phtfacac)3–]) MIL with a dispersion of the supporting media, polypropylene glycol, at room temperature for up to a 7 and 15 day period, respectively. High-quality RNA treated with ribonuclease A (RNase A) was recovered from the tetra(1-octylimidazole)cobaltate(II) di(l-glutamate) ([Co(OIM)42+][Glu–]2) and tetra(1-octylimidazole)cobaltate(II) di(l-aspartate) ([Co(OIM)42+][Asp–]2) MILs after a 24 h period at room temperature. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and agarose gel electrophoresis were used to determine the effect of RNA preservation. Furthermore, the preservation mechanism was investigated by exploring the partitioning of RNase A into the MIL using high-performance liquid chromatography.

Fluorescence quenching of the SYBR Green I-dsDNA complex by in situ generated magnetic ionic liquids.

Magnetic ionic liquids (MILs) with metal-containing cations are promising extraction solvents that provide fast and high efficiency extraction of DNA. Hydrophobic MILs can be generated in situ in a methodology called in situ dispersive liquid-liquid microextraction. To consolidate the sample preparation workflow, it is desirable to directly use the DNA-enriched MIL microdroplet in the subsequent analytical detection technique. Fluorescence-based techniques employed for DNA detection often utilize SYBR Green I, a DNA binding dye that exhibits optimal fluorescence when bound to double-stranded DNA. However, the MIL may hinder the fluorescence signal of the SYBR Green I-dsDNA complex due to quenching. In this study, MILs with metal-containing cations wereselected and their fluorescence quenching effects evaluated using Fӧrster Resonance Energy Transfer and quantified using Stern-Volmer models. The MILs were based on N-substituted imidazole ligands (with butyl- and benzyl- groups as substituents) coordinated to Ni2+ or Co2+ metal centers as cations, and paired with chloride anions. The effects of NiCl2 and CoCl2 salts and of the 1-butyl-3-methylimidazolium chloride ionic liquid on the fluorophore complex were also studied to understand the components of the MIL structure that are responsible for quenching. The metal within the MIL chemical structure was found to be the main component contributing to fluorescence quenching. Fӧrster critical distances between 11.9 and 18.8Å were obtained for the MILs, indicating that quenching is likely not due to non-radiative energy transfer but rather to spin-orbit coupling or excited-state electron transfer. The MILs were able to be directly used in qPCR and fluorescence emission measurements using a microplate reader for detection, demonstrating their applicability in fluorescence-based detection methods. Graphical abstract.

Maximizing Ion-Tagged Oligonucleotide Loading on Magnetic Ionic Liquid Supports for the Sequence-Specific Extraction of Nucleic Acids.

Targeted nucleic acid analysis requires the highly selective extraction of desired DNA fragments in order to minimize interferences from samples with abundant heterogeneous sequences. We previously reported a method based on functionalized oligonucleotide probes known as ion-tagged oligonucleotides (ITOs) that hybridize with complementary DNA targets for subsequent capture using a hydrophobic magnetic ionic liquid (MIL) support. Although the ITO-MIL approach enriched specific DNA sequences in quantities comparable to a commercial magnetic bead-based method, the modest affinity of the ITO for the hydrophobic MIL limited the yield of DNA targets, particularly when stringent wash conditions were applied to remove untargeted DNA. Here, we report the synthesis and characterization of a series of ITOs in which functional groups were installed within the cation and anion components of the tag moiety in order to facilitate loading of the ITO to the MIL support phase. In addition to hydrophobic interactions, we demonstrate that π-π stacking and fluorophilic interactions can be exploited for loading oligonucleotide probes onto MILs. Using a disubstituted ion-tagged oligonucleotide (DTO) possessing two linear C8 groups, nearly quantitative loading of the probe onto the MIL support was achieved. The enhanced stability of the DTO within the MIL solvent permitted successive wash steps without the loss of the DNA target compared to a monosubstituted ITO with a single C8 group that was susceptible to increased loss of analyte. Furthermore, the successful capture of a 120 bp KRAS fragment from human plasma samples followed by real-time quantitative polymerase chain reaction (qPCR) amplification is demonstrated.

Sequence-specific preconcentration of a mutation prone KRAS fragment from plasma using ion-tagged oligonucleotides coupled to qPCR compatible magnetic ionic liquid solvents

Circulating tumor DNA (ctDNA) is a source of mutant DNA found in plasma and holds great promise in guiding cancer diagnostics, prognostics, and treatment. However, ctDNA fragments are challenging to detect in plasma due to their low abundance compared to wild-type DNA. In this study, a series of ion-tagged oligonucleotides (ITO) were synthesized using thiol-ene click chemistry and designed to selectively anneal target DNA. The ITO-DNA duplex was subsequently captured using a hydrophobic magnetic ionic liquid (MIL) as a liquid support. Extracted target DNA was quantified by adding the DNA-enriched MIL to the quantitative polymerase chain reaction (qPCR) buffer to streamline the extraction procedure. Clinically relevant concentrations of the mutation prone KRAS fragment, which has been linked to colorectal, lung, and bladder cancer, were preconcentrated using the ITO-MIL strategy allowing for enrichment factors as high as 19.49 ± 1.44 from pure water and 4.02 ± 0.50 from 10-fold diluted plasma after a 1 min extraction. Preconcentration could only be achieved when adding the ITO probe to the sample validating the selectivity of the ITO in the capture process. In addition, the amplification efficiency of qPCR was not affected when performing extractions from a diluted-plasma matrix demonstrating that the ITO-MIL approach coupled to direct-qPCR can be used to quantitate DNA from complex matrices. In comparison, commercially available steptavidin-coated magnetic beads were observed to lose selectivity when performing extractions from a 10-fold diluted plasma matrix. The selectivity of the ITO-MIL method, coupled with the ability to rapidly preconcentrate clinically relevant concentrations of target DNA from 10-fold diluted plasma, suggests that this method has the potential to be applied towards the extraction of ctDNA fragments from clinical samples.

In situ generation of hydrophobic magnetic ionic liquids in stir bar dispersive liquid-liquid microextraction coupled with headspace gas chromatography

For the first time, an in situ stir bar dispersive liquid-liquid microextraction approach has been developed and coupled with headspace gas chromatography-mass spectrometry for the determination of a group of organic pollutants. The method exploits a new generation of magnetic ionic liquids (MILs) that contain paramagnetic cations based on Ni2+ or Co2+ metal centers coordinated with either N-butylimidazole or N-octylimidazole ligands and chloride anions. The reactants are added to an aqueous solution containing a high field neodymium rod magnet, followed by the addition of the bis[(trifluoromethyl)sulfonyl]imide anion that promotes a metathesis reaction for the in situ generation of a hydrophobic MIL. Concurrently, a high stirring rate is maintained to exceed the magnetic field of the rod magnet and disperse the generated MIL in the sample solution. When stirring is stopped, the MIL coats the rod magnet due to its paramagnetic nature, facilitating the MIL transfer and subsequent desorption and analysis. Under optimum conditions, the method required a 2.5–18% (w/v) aqueous solution of sodium chloride, 10 mL of sample, 20 or 30 mg of MIL, the addition of a small volume of dispersive solvent, and stirring for 5–7.5 min, depending on the MIL. The method provided limits of detection (LODs) down to 10 μg L−1, adequate reproducibility (with relative standard deviation values lower than 10% for a spiked level of 80 μg L−1), and relative recoveries between 72.5% and 102%. Furthermore, the method was successfully applied in the analysis of tap and mineral water.

In situ formation of hydrophobic magnetic ionic liquids for dispersive liquid-liquid microextraction

A new class of magnetic ionic liquid (MIL) containing paramagnetic cations has been applied for in situ dispersive liquid-liquid microextraction in the determination of both polar and non-polar pollutants, including ultraviolet filters, polycyclic aromatic hydrocarbons, alkylphenols, a plasticizer and a preservative in aqueous samples. The MILs were based on cations containing Ni(II) metal centers coordinated with four N-alkylimidazole ligands and chloride anions. The MILs were capable of undergoing in situ metathesis reaction with the bis[(trifluoromethyl)sulfonyl]imide ([NTf2−]) anion during the microextraction procedure, generating a water-immiscible extraction solvent containing the preconcentrated analytes. The MIL was then isolated by magnetic separation, followed by direct analysis using reversed-phase high performance liquid chromatography with diode array detection. Among all of the studied MILs, those containing the N-butylimidazole and N-benzylimidazole ligands ([Ni(C4IM)42+]2[Cl-] and [Ni(BeIM)42+]2[Cl-], respectively) exhibited the best extraction performance. The method under optimum conditions required 5 mL of sample at pH 3, 20 mg of [Ni(C4IM)42+]2[Cl-] or 30 mg of [Ni(BeIM)42+]2[Cl-], 300 μL of acetone or acetonitrile as dispersive solvent (depending on the MIL), a 1:2 M ratio of MIL to [NTf2−], and 3 min of vortex. The developed method achieved higher extraction efficiency compared to the conventional MIL-dispersive liquid-liquid microextraction mode, with extraction efficiencies of 46.8–88.6% and 65.4–97.0% for the [Ni(C4IM)42+]2[Cl-] and the [Ni(BeIM)42+]2[Cl-] MILs (at a spiked level of 81 μg L-1), respectively, limits of detection down to 5.2 μg L-1, and inter-day relative standard deviation lower than 16%.

Magnetic ionic liquid-enhanced isothermal nucleic acid amplification and its application to rapid visual DNA analysis

Isothermal nucleic acid amplification (INAA) techniques such as loop-mediated isothermal amplification (LAMP) and isothermal multiple-self-matching-initiated amplification (IMSA) constitute simple and rapid approaches for the detection of pathogens. However, due to the employment of multiple primers, the detection of LAMP and IMSA products is easily influenced by high background signals from primer dimer-based nonspecific nucleic acid amplification (NSA) products. Moreover, time-consuming sample preparation steps are often required for the isolation of sufficiently pure nucleic acid prior to INAA. To address these drawbacks, hydrophobic magnetic ionic liquids (MILs) were used to rapidly preconcentrate DNA from complex biological samples followed by direct amplification by LAMP and IMSA. Careful control of the components within the isothermal buffer permitted direct addition of DNA-enriched MIL to the INAA reaction mixture, thereby circumventing tedious purification procedures that are ordinarily required prior to downstream DNA amplification. When added directly to INAA reactions, MIL solvents released metal ions that ultimately inhibited the primer dimer-mediated NSA, resulting in a flat or decreased baseline signal in no-template control samples and short threshold time for positive reactions. Using a MIL-based single droplet DNA extraction method, MIL-enhanced INAA reaction system, and a handheld 3D printed device for visual detection of the amplified product in customized tubes, we demonstrate the potential of the MIL-based approach for the onsite analysis of DNA from pathogens.

Magnetic ionic liquid assisted single‐drop microextraction of ascorbic acid before its voltammetric determination

For the first time, we coupled a microextraction technique using a magnetic ionic liquid with voltammetric determination. A hydrophobic magnetic ionic liquid that contains the tetrachloromanganate(II) anion, namely, aliquat tetrachloromanganate(II), was synthesized and used for the extraction of ascorbic acid from aqueous solutions followed by voltammetric determination. The extraction procedure was carried out using a single drop microextraction technique in which the ascorbic acid containing magnetic ionic liquid was separated with a magnet and then cast onto the surface of a carbon paste electrode modified with TiO2 nanoparticles for the voltammetric quantification of the extracted ascorbic acid. Electrochemical quantification was carried out in a blank phosphate buffer solution. After optimizing different experimental conditions, a linear concentration range of 1.50-40.0nM with a detection limit of 0.43nM was obtained for the determination of ascorbic acid. The presented approach was successfully applied to the determination of ascorbic acid in samples of vitamin C effervescent tablets and orange juice.

Synthesis and characterization of low viscosity hexafluoroacetylacetonate-based hydrophobic magnetic ionic liquids

The properties of low viscosity, hydrophobic magnetic ionic liquids featuring transition and rare earth metal hexafluoroacetylacetonate chelated anions paired with the trihexyl(tetradecyl)phosphonium cation are studied.

Faster dispersive liquid-liquid microextraction methods using magnetic ionic liquids as solvents

Three hydrophobic magnetic ionic liquids (MILs) containing the tetrachloromanganate(II) (MnCl42−) anion, namely, aliquat tetrachloromanganate(II) ([Aliquat+]2[MnCl42−]), methyltrioctylammonium [MnCl42−] ([N1,8,8,8+]2[MnCl42−]), and trihexyltetradecylphosphonium [MnCl42−] ([P6,6,6,14+]2[MnCl42−]) were employed as extraction solvents in DLLME coupled to high-performance liquid chromatography (HPLC) employing UV detection. The MILs were developed with the features of magnetic susceptibility to permit rapid retrieval of the extraction solvent, hydrophobicity to allow for phase separation from water, and mobile phase compatibility with reversed phase HPLC. Additionally, the MILs were customized to minimize hydrolysis of the anionic component in aqueous media as well as reduce absorbance when subjected to HPLC. The three MILs were applied for the extraction of pharmaceutical drugs, phenolics, insecticides, and polycyclic aromatic hydrocarbons. The disperser solvent type, disperser solvent volume, mass of MIL, extraction time, the pH of the sample solution, and salt concentration were studied in order to achieve optimal extraction efficiency for each MIL. The [P6,6,6,14+]2[MnCl42−] MIL exhibited the best extraction efficiencies for most of the target analytes compared to the other MILs. Good linearity was obtained using this MIL with correlation coefficients (R) varying from 0.997 to 0.999. The limits of detection (LODs) of all analytes ranged from 0.25 to 1.00μgL−1. The relative recovery was studied in lake water and river water. The relative recovery in lake water varied from 53.8% to 114.7% at a spiked concentration of 20μgL−1 (5μgL−1 for phenanthrene) and from 52.1% to 106.7% at 150μgL−1 (37.5μgL−1 for phenanthrene). In river water, the relative recovery varied from 44.6% to 110.7% at a spiked concentration of 20μgL−1 (5μgL−1 for phenanthrene) and 42.9% to 83.6% at 150μgL−1 (37.5μgL−1 for phenanthrene).

Synthesis and characterization of the physicochemical and magnetic properties for perfluoroalkyl ester and Fe(iii) carboxylate-based hydrophobic magnetic ionic liquids

The hydrophobic and magnetic properties of magnetic ionic liquids can be controlled using cation functionalization or anion modification.

Extraction of DNA by magnetic ionic liquids: tunable solvents for rapid and selective DNA analysis.

DNA extraction represents a significant bottleneck in nucleic acid analysis. In this study, hydrophobic magnetic ionic liquids (MILs) were synthesized and employed as solvents for the rapid and efficient extraction of DNA from aqueous solution. The DNA-enriched microdroplets were manipulated by application of a magnetic field. The three MILs examined in this study exhibited unique DNA extraction capabilities when applied toward a variety of DNA samples and matrices. High extraction efficiencies were obtained for smaller single-stranded and double-stranded DNA using the benzyltrioctylammonium bromotrichloroferrate(III) ([(C8)3BnN(+)][FeCl3Br(-)]) MIL, while the dicationic 1,12-di(3-hexadecylbenzimidazolium)dodecane bis[(trifluoromethyl)sulfonyl]imide bromotrichloroferrate(III) ([(C16BnIM)2C12(2+)][NTf2(-), FeCl3Br(-)]) MIL produced higher extraction efficiencies for larger DNA molecules. The MIL-based method was also employed for the extraction of DNA from a complex matrix containing albumin, revealing a competitive extraction behavior for the trihexyl(tetradecyl)phosphonium tetrachloroferrate(III) ([P6,6,6,14(+)][FeCl4(-)]) MIL in contrast to the [(C8)3BnN(+)][FeCl3Br(-)] MIL, which resulted in significantly less coextraction of albumin. The MIL-DNA method was employed for the extraction of plasmid DNA from bacterial cell lysate. DNA of sufficient quality and quantity for polymerase chain reaction (PCR) amplification was recovered from the MIL extraction phase, demonstrating the feasibility of MIL-based DNA sample preparation prior to downstream analysis.

Synthetic Strategies for Tailoring the Physicochemical and Magnetic Properties of Hydrophobic Magnetic Ionic Liquids

Magnetic ionic liquids (MILs) are a subclass of ionic liquids (ILs) containing paramagnetic components and are readily manipulated by an external magnetic field. Due to their hydrophilic nature, very few applications of MILs in aqueous systems have been reported. In this study, three general classes of hydrophobic MILs including monocationic, symmetrical/unsymmetrical dicationic, and symmetrical/unsymmetrical tricationic MILs were synthesized and characterized. By tuning the structure of the MIL, various physicochemical properties including water solubility, magnetic susceptibility, and melting point were regulated. MILs synthesized with the benzimidazolium cation were shown to exhibit lower water solubility (0.1% (w/v)) when compared to those containing imidazolium cations (0.25% (w/v)). By incorporating asymmetry into the cationic component of the MIL, the melting point of dicationic MILs was lowered while the effective magnetic moment (μeff) and hydrophobicity remained unchanged. Tricationic MILs paire...

Magnetic ionic liquids as PCR-compatible solvents for DNA extraction from biological samples.

A polymerase chain reaction (PCR) buffer was systematically designed to relieve the inhibition caused by hydrophobic magnetic ionic liquids (MILs). We describe a simple, rapid method for MIL-based plasmid DNA extraction from crude bacterial cell lysate in which DNA-enriched MIL is transferred directly to a PCR tube for analysis.