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

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.

Development of an innovative and sustainable one-step method for rapid plant DNA isolation for targeted PCR using magnetic ionic liquids

BACKGROUND

Nowadays, there is an increasing demand for fast and reliable plant biomolecular analyses. Conventional methods for the isolation of nucleic acids are time-consuming and require multiple and often non-automatable steps to remove cellular interferences, with consequence that sample preparation is the major bottleneck in the bioanalytical workflow. New opportunities have been created by the use of magnetic ionic liquids (MILs) thanks to their affinity for nucleic acids.

RESULTS

In the present study, a MIL-based magnet-assisted dispersive liquid-liquid microextraction (maDLLME) method was optimized for the extraction of genomic DNA from Arabidopsis thaliana (L.) Heynh leaves. MILs containing different metal centers were tested and the extraction method was optimized in terms of MIL volume and extraction time for purified DNA and crude lysates. The proposed approach yielded good extraction efficiency and is compatible with both quantitative analysis through fluorimetric-based detection and qualitative analysis as PCR amplification of multi and single locus genes. The protocol was successfully applied to a set of plant species and tissues.

CONCLUSIONS

The developed MIL-based maDLLME approach exhibits good enrichment of nucleic acids for extraction of template suitable for targeted PCR; it is very fast, sustainable and potentially automatable thereby representing a powerful tool for screening plants rapidly using DNA-based methods.

Magnetic ionic liquids based on transition metal complexes with N-alkylimidazole ligands

Nickel(ii), cobalt(ii) and manganese(ii) N-alkylimidazole bis[(trifluoromethyl)sulfonyl]imide magnetic ionic liquids were synthesized from their chloride intermediates and their physicochemical properties studied.

Extraction of DNA from complex biological sample matrices using guanidinium ionic liquid modified magnetic nanocomposites

A series of guanidinium ionic liquid modified magnetic chitosan/graphene oxide (GIL-MCGO) nanocomposites have been prepared for DNA extraction via magnetic solid-phase extraction technology. These nanocomposites are of only 20 nanometers in diameter. Single stranded DNA or DNA sodium salts that were absorbed by GIL-MCGO could be quickly collected by an external magnet and extracted. The DNA extraction efficiency of 11 GIL-MCGO nanocomposites was evaluated using NanoDrop. Factors that could impact the DNA extraction process, such as pH, temperature, extraction time, and ionic strength were systematically investigated via single-factor experimental analysis. Under the optimum extraction conditions, a maximum DNA extraction capacity of 233.0 ± 0.4 mg g⁻¹ of GIL-MCGO nanocomposite was achieved. The solid phase extraction method based on GIL-MCGO nanocomposites has been demonstrated with the extraction of DNA from a series of complex sample matrices, including single stranded DNA samples, salmon sperm DNA sodium salt, human whole blood and E. coli cell lysate. The DNA extracted by using the GIL-MCGO nanocomposites are well suitable for PCR amplifications. In addition, an initial study on the interaction between GIL-MCGO and DNA was conducted: the preference of GIL-MCGO on DNA absorption with varying base composition was tested. Only a slight loss in the DNA extraction efficiency of GIL-MCGO was observed after four extraction–desorption cycles, proving excellent regeneration performance and recyclability of the GIL-MCGO nanocomposites in the DNA extraction process.

The DNA extracted from biological samples by using the GIL-MCGO nanocomposites are well suitable for PCR amplifications.

Coupling oligonucleotides possessing a poly-cytosine tag with magnetic ionic liquids for sequence-specific DNA analysis

Oligonucleotide probes were designed with a poly-cytosine region that facilitates stable anchoring to a magnetic ionic liquid support. By tethering a recognition sequence to the poly-C tag, the resulting diblock oligonucleotides distinguished single-nucleotide variants and captured DNA targets from interfering genomic DNA and cell lysate for qPCR amplification.

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.

Review on sample preparation methods for oligonucleotides analysis by liquid chromatography

Antisense oligonucleotides have been successfully investigated for the treatment of different types of diseases. Detection and determination of antisense oligonucleotides and their metabolites are necessary for drug development and evaluation. This review focuses mainly on the first step of the analysis of oligonucleotides i.e. the sample preparation stage, and in particular on the techniques used for liquid chromatography and liquid chromatography coupled with mass spectrometry. Exceptional sample preparation techniques are required as antisense oligonucleotides need to be determined in complex biological matrices. The text discusses general issues in oligonucleotide sample preparation and approaches to their solution. The most popular techniques i.e. protein precipitation, protein enzyme digestion and liquid-liquid extraction are reviewed. Solid phase extraction methods are discussed and the issues connected with the application of each method are highlighted. Other newly reported promising techniques are also described. Finally, there is a summary of actually used techniques and the indication of the direction of future research.

Preconcentration of DNA using magnetic ionic liquids that are compatible with real-time PCR for rapid nucleic acid quantification

Nucleic acid extraction and purification represents a major bottleneck in DNA analysis. Traditional methods for DNA purification often require reagents that may inhibit quantitative polymerase chain reaction (qPCR) if not sufficiently removed from the sample. Approaches that employ magnetic beads may exhibit lower extraction efficiencies due to sedimentation and aggregation. In this study, four hydrophobic magnetic ionic liquids (MILs) were investigated as DNA extraction solvents with the goal of improving DNA enrichment factors and compatibility with downstream bioanalytical techniques. By designing custom qPCR buffers, we directly incorporated DNA-enriched MILs including trihexyl(tetradecyl)phosphonium tris(hexafluoroacetylaceto)nickelate(II) ([P_6,6,6,14⁺][Ni(hfacac)₃^-]), [P_6,6,6,14⁺] tris(hexafluoroacetylaceto)colbaltate(II) ([Co(hfacac)₃^-]), [P_6,6,6,14⁺] tris(hexafluoroacetylaceto)manganate(II) ([Mn(hfacac)₃^-]), or [P_6,6,6,14⁺] tetrakis(hexafluoroacetylaceto)dysprosate(III) ([Dy(hfacac)₄^-]) into reaction systems, thereby circumventing the need for time-consuming DNA recovery steps. Incorporating MILs into the reaction buffer did not significantly impact the amplification efficiency of the reaction (91.1%). High enrichment factors were achieved using the [P_6,6,6,14⁺][Ni(hfacac)₃^-] MIL for the extraction of single-stranded and double-stranded DNA with extraction times as short as 2 min. When compared to a commercial magnetic bead-based platform, the [P_6,6,6,14⁺][Ni(hfacac)₃^-] MIL was capable of producing higher enrichment factors for single-stranded DNA and similar enrichment factors for double-stranded DNA. The MIL-based method was applied for the extraction and direct qPCR amplification of mutation prone-KRAS oncogene fragment in plasma samples. Graphical abstract Magnetic ionic liquid solvents are shown to preconcentrate sufficient KRAS DNA template from an aqueous solution in as short as 2 min without using chaotropic salts or toxic organic solvents. By using custom-designed qPCR buffers, DNA can be directly amplified and quantified from four MILs examined in this study.

Biological and nanotechnological applications using interactions between ionic liquids and nucleic acids

Nucleic acids have emerged as powerful biological and nanotechnological tools. In biological and nanotechnological experiments, methods of extracting and purifying nucleic acids from various types of cells and their storage are critical for obtaining reproducible experimental results. In nanotechnological experiments, methods for regulating the conformational polymorphism of nucleic acids and increasing sequence selectivity for base pairing of nucleic acids are important for developing nucleic acid-based nanomaterials. However, dearth of media that foster favourable behaviour of nucleic acids has been a bottleneck for promoting the biology and nanotechnology using the nucleic acids. Ionic liquids (ILs) are solvents that may be potentially used for controlling the properties of the nucleic acids. Here, we review researches regarding the behaviour of nucleic acids in ILs. The efficiency of extraction and purification of nucleic acids from biological samples is increased by IL addition. Moreover, nucleic acids in ILs show long-term stability, which maintains their structures and enhances nuclease resistance. Nucleic acids in ILs can be used directly in polymerase chain reaction and gene expression analysis with high efficiency. Moreover, the stabilities of the nucleic acids for duplex, triplex, and quadruplex (G-quadruplex and i-motif) structures change drastically with IL cation-nucleic acid interactions. Highly sensitive DNA sensors have been developed based on the unique changes in the stability of nucleic acids in ILs. The behaviours of nucleic acids in ILs detailed here should be useful in the design of nucleic acids to use as biological and nanotechnological tools.

A bench-top automated workstation for nucleic acid isolation from clinical sample types

Systems that automate extraction of nucleic acid from cells or viruses in complex clinical matrices have tremendous value even in the absence of an integrated downstream detector. We describe our bench-top automated workstation that integrates our previously-reported extraction method - TruTip - with our newly-developed mechanical lysis method. This is the first report of this method for homogenizing viscous and heterogeneous samples and lysing difficult-to-disrupt cells using "MagVor": a rotating magnet that rotates a miniature stir disk amidst glass beads confined inside of a disposable tube. Using this system, we demonstrate automated nucleic acid extraction from methicillin-resistant Staphylococcus aureus (MRSA) in nasopharyngeal aspirate (NPA), influenza A in nasopharyngeal swabs (NPS), human genomic DNA from whole blood, and Mycobacterium tuberculosis in NPA. The automated workstation yields nucleic acid with comparable extraction efficiency to manual protocols, which include commercially-available Qiagen spin column kits, across each of these sample types. This work expands the scope of applications beyond previous reports of TruTip to include difficult-to-disrupt cell types and automates the process, including a method for removal of organics, inside a compact bench-top workstation.

Aqueous ionic liquids in comparison with standard co-solutes : Differences and common principles in their interaction with protein and DNA structures

Ionic liquids (ILs) are versatile solvents for a broad range of biotechnological applications. Recent experimental and simulation results highlight the potential benefits of dilute ILs in aqueous solution (aqueous ILs) in order to modify protein and DNA structures systematically. In contrast to a limited number of standard co-solutes like urea, ectoine, trimethylamine-N-oxide (TMAO), or guanidinium chloride, the large amount of possible cation and anion combinations in aqueous ILs can be used to develop tailor-made stabilizers or destabilizers for specific purposes. In this review article, we highlight common principles and differences between aqueous ILs and standard co-solutes with a specific focus on their underlying macromolecular stabilization or destabilization behavior. In combination with statistical thermodynamics theories, we present an efficient framework, which is used to classify structure modification effects consistently. The crucial importance of enthalpic and entropic contributions to the free energy change upon IL-assisted macromolecular unfolding in combination with a complex destabilization mechanism is described in detail. A special focus is also set on aqueous IL-DNA interactions, for which experimental and simulation outcomes are summarized and discussed in the context of previous findings.

Ionic liquid induced G-quadruplex formation and stabilization: spectroscopic and simulation studies

Among different polymorphs of DNA, G-quadruplex (GQ) formation in guanine rich sequences has received special attention due to its direct relevance to cellular aging and abnormal cell growths. To date, smaller ions like Na⁺, K⁺, Li⁺, and NH₄⁺ are the best possible selective GQ stabilizing materials. Herein, we report that an ionic liquid (IL), i.e. guanidinium tris(pentafluoroethyl)trifluorophosphate, can not only instigate the GQ formation in the absence of conventional GQ forming ions (like Na⁺, K⁺, NH₄⁺, etc.), but also stabilizes the GQ structure. This conformational transition has been confirmed through different spectroscopic tools and molecular dynamics (MD) simulation studies. MD simulation shows that one of the guanidinium cations resides in the G-tetrad core, while bulky anions prefer to stay near the GQ surface resulting in GQ formation and stabilization. This study thus brings out a special type of ionic liquid that acts as a GQ stabilizer. The origin of GQ stabilization by IL presented here may also help in the future design of IL for GQ formation and stabilization.

Dispersive liquid–liquid microextraction using magnetic room temperature ionic liquid for extraction of ultra-trace amounts of parabens

In this work, a dispersive liquid–liquid microextraction method using methyltrioctylammonium tetrachloroferrate was employed for the extraction of ultratrace amounts of parabens in water, beer and beverage samples.

Recent advances on ionic liquid uses in separation techniques

The molten organic salts with melting point below 100°C, commonly called ionic liquids (ILs) have found numerous uses in separation sciences due to their exceptional properties as non molecular solvents, namely, a negligible vapor pressure, a high thermal stability, and unique solvating properties due to polarity and their ionic character of molten salts. Other properties, such as viscosity, boiling point, water solubility, and electrochemical window, are adjustable playing with which anion is associated with which cation. This review focuses on recent development of the uses of ILs in separation techniques actualizing our 2008 article (same authors, J. Chromatogr. A, 1184 (2008) 6-18) focusing on alkyl methylimidazolium salts. These developments include the use of ILs in nuclear waste reprocessing, highly thermally stable ILs that allowed for the introduction of polar gas chromatography capillary columns able to work at temperature never seen before (passing 300°C), the use of ILs in liquid chromatography and capillary electrophoresis, and the introduction of tailor-made ILs for mass spectrometry detection of trace anions at the few femtogram level. The recently introduced deep eutectic solvents are not exactly ILs, they are related enough so that their properties and uses in countercurrent chromatography are presented.

Ecotoxicological evaluation of magnetic ionic liquids

Although magnetic ionic liquids (MILs) are not yet industrially applied, their continued development and eventual commercial use may lead to their appearance into the aquatic ecosystem through accidental spills or effluents, consequently promoting aquatic contaminations. Furthermore, the deficient information and uncertainty surrounding the environmental impact of MILs could be a major barrier to their widespread industrial application and international registration. Thus, in the present work, a range of cholinium salt derivatives with magnetic properties was synthesized and their ecotoxicity was evaluated towards the luminescent bacteria Vibrio fischeri. The results suggest that all MILs structures tested are moderately toxic, or even toxic, to the bacteria. Furthermore, their toxicity is highly dependent on the structural modifications of the cation, namely the alkyl side chain length and the number of hydroxyethyl groups, as well as the atomic number of the metal anion. Finally, from the magnetic anions evaluated, the [MnCl₄]^2- is the less toxic. In order to improve the knowledge for the prospective design of environmentally safer MILs, it is important to expand this study to other aquatic organisms at different trophic levels.

Synthesis and application of magnetic deep eutectic solvents: Novel solvents for ultrasound assisted liquid-liquid microextraction of thiophene

Two novel magnetic deep eutectic solvents (MDESs), comprised of cheap and simple components named [choline chloride/phenol] [FeCl₄] and [choline chloride/ethylene glycol] [FeCl₄] were prepared and characterized by CHN elemental analysis, proton nuclear magnetic resonance (¹H NMR), vibrating sample magnetometery (VSM), Raman, Fourier transform-infrared (FT-IR) and UV-Vis spectrometery. The extraction efficiency of the prepared MDESs has been investigated in ultrasound assisted liquid-liquid microextraction based MDES (UALLME-MDES). Briefly, MDESs were added to n-heptan containing thiophene. Then, MDESs were dispersed in n-heptane by sonication. After that, microdroplets of MDESs were collected by a magnet and the remained concentration of thiophene in n-heptane phase was analyzed by GC-FID. The results indicated that [choline chloride/phenol] [FeCl₄] has higher extraction efficiency than [choline chloride/ethylene glycol] [FeCl₄]. This work opens a new way to the application of MDESs.

Room-temperature ionic liquids meet bio-membranes: the state-of-the-art

Room-temperature ionic liquids (RTIL) are a new class of organic salts whose melting temperature falls below the conventional limit of 100 °C. Their low vapor pressure, moreover, has made these ionic compounds the solvents of choice of the so-called green chemistry. For these and other peculiar characteristics, they are increasingly used in industrial applications. However, studies of their interaction with living organisms have highlighted mild to severe health hazards. Since their cytotoxicity shows a positive correlation with their lipophilicity, several chemical-physical studies of their interactions with biomembranes have been carried out in the last few years, aiming to identify the molecular mechanisms behind their toxicity. Cation chain length and anion nature of RTILs have seemed to affect lipophilicity and, in turn, their toxicity. However, the emerging picture raises new questions, points to the need to assess toxicity on a case-by-case basis, but also suggests a potential positive role of RTILs in pharmacology, bio-medicine and bio-nanotechnology. Here, we review this new subject of research, and comment on the future and the potential importance of this emerging field of study.

Use of Dimethyl Pimelimidate with Microfluidic System for Nucleic Acids Extraction without Electricity

The isolation of nucleic acids in the lab on a chip is crucial to achieve the maximal effectiveness of point-of-care testing for detection in clinical applications. Here, we report on the use of a simple and versatile single-channel microfluidic platform that combines dimethyl pimelimidate (DMP) for nucleic acids (both RNA and DNA) extraction without electricity using a thin-film system. The system is based on the adaption of DMP into nonchaotropic-based nucleic acids and the capture of reagents into a low-cost thin-film platform for use as a microfluidic total analysis system, which can be utilized for sample processing in clinical diagnostics. Moreover, we assessed the use of the DMP system for the extraction of nucleic acids from various samples, including mammalian cells, bacterial cells, and viruses from human disease, and we also confirmed that the quality and quantity of the nucleic acids extracted were sufficient to allow for the robust detection of biomarkers and/or pathogens in downstream analysis. Furthermore, this DMP system does not require any instruments and electricity, and has improved time efficiency, portability, and affordability. Thus, we believe that the DMP system may change the paradigm of sample processing in clinical diagnostics.

Rapid preconcentration of viable bacteria using magnetic ionic liquids for PCR amplification and culture-based diagnostics

In this study, a series of magnetic ionic liquids (MILs) were investigated for the extraction and preconcentration of bacteria from aqueous samples. By dispersing small volumes (e.g., 15 μL) of MIL within an aqueous cell suspension, bacteria were rapidly extracted and isolated using a magnetic field. Of the seven hydrophobic MILs examined, the trihexyl(tetradecyl)phosphonium Ni(II) hexafluoroacetylacetonate ([P₆₆₆₁₄⁺][Ni(hfacac)₃^-]) MIL exhibited the greatest enrichment of viable Escherichia coli K12 when coupled with microbiological culture as the detection method. The MIL-based strategy was applied for the preconcentration of E. coli from aqueous samples to obtain enrichment factors (E _F) as high as 44.6 in less than 10 min. The MIL extraction approach was also interfaced with polymerase chain reaction (PCR) amplification where the positive detection of E. coli was achieved with the [P₆₆₆₁₄⁺][Co(hfacac)₃^-], [P₆₆₆₁₄⁺][Ni(hfacac)₃^-], [P₆₆₆₁₄⁺][Dy(hfacac)₄^-], and [P₆₆₆₁₄⁺][Nd(hfacac)₄^-] MILs. While direct sampling of an aqueous cell suspension at a concentration of 1.68 × 10⁴ colony-forming units (CFUs) mL^-1 yielded no amplicon when subjected to PCR, extraction of the sample with the [P₆₆₆₁₄⁺][Ni(hfacac)₃^-] MIL under optimized conditions provided sufficient enrichment of E. coli for amplicon detection. Importantly, the enrichment of bacteria using the Ni(II)-, Co(II)-, and Dy(III)-based MILs was compatible with real-time quantitative PCR amplification to dramatically improve sample throughput and lower detection limits to 1.0 × 10² CFUs mL^-1. The MIL-based method is much faster than existing enrichment approaches that typically require 24-h cultivation times prior to detection and could potentially be applied for the preconcentration of a variety of Gram-negative bacteria from aqueous samples. Graphical abstract Magnetic ionic liquid solvents rapidly preconcentrate viable E. coli cells for unambiguous pathogen detection using microbiological culture and qPCR.

Ion-Tagged Oligonucleotides Coupled with a Magnetic Liquid Support for the Sequence-Specific Capture of DNA

The isolation of specific nucleic acid sequences is a major bottleneck in molecular diagnostics. Magnetic beads/particles are typically used as solid supports for the capture of DNA targets to improve sample throughput but aggregate over time resulting in lower capture efficiency and obstruction of liquid handling devices. Herein, we describe a particle-free approach to sequence-specific DNA extraction using a magnetic liquid support and ion-tagged oligonucleotide (ITO) probes. ITO conjugates were synthesized with the highest yields ever achieved for the radical thiol-ene coupling of a substrate and oligonucleotide. In addition to distinguishing nucleotide mismatches, the ITO and magnetic liquid-based approach was more sensitive than a commercial magnetic bead-based method for the capture of target DNA from a pool of interfering genomic DNA.

Ionic-Liquid-Mediated Extraction and Separation Processes for Bioactive Compounds: Past, Present, and Future Trends

Ionic liquids (ILs) have been proposed as promising media for the extraction and separation of bioactive compounds from the most diverse origins. This critical review offers a compilation on the main results achieved by the use of ionic-liquid-based processes in the extraction and separation/purification of a large range of bioactive compounds (including small organic extractable compounds from biomass, lipids, and other hydrophobic compounds, proteins, amino acids, nucleic acids, and pharmaceuticals). ILs have been studied as solvents, cosolvents, cosurfactants, electrolytes, and adjuvants, as well as used in the creation of IL-supported materials for separation purposes. The IL-based processes hitherto reported, such as IL-based solid-liquid extractions, IL-based liquid-liquid extractions, IL-modified materials, and IL-based crystallization approaches, are here reviewed and compared in terms of extraction and separation performance. The key accomplishments and future challenges to the field are discussed, with particular emphasis on the major lacunas found within the IL community dedicated to separation processes and by suggesting some steps to overcome the current limitations.

Hydrophobic ionic liquids for quantitative bacterial cell lysis with subsequent DNA quantification

DNA is one of the most frequently analyzed molecules in the life sciences. In this article we describe a simple and fast protocol for quantitative DNA isolation from bacteria based on hydrophobic ionic liquid supported cell lysis at elevated temperatures (120-150 °C) for subsequent PCR-based analysis. From a set of five hydrophobic ionic liquids, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide was identified as the most suitable for quantitative cell lysis and DNA extraction because of limited quantitative PCR inhibition by the aqueous eluate as well as no detectable DNA uptake. The newly developed method was able to efficiently lyse Gram-negative bacterial cells, whereas Gram-positive cells were protected by their thick cell wall. The performance of the final protocol resulted in quantitative DNA extraction efficiencies for Gram-negative bacteria similar to those obtained with a commercial kit, whereas the number of handling steps, and especially the time required, was dramatically reduced. Graphical Abstract After careful evaluation of five hydrophobic ionic liquids, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([BMPyr + ][Ntf 2- ]) was identified as the most suitable ionic liquid for quantitative cell lysis and DNA extraction. When used for Gram-negative bacteria, the protocol presented is simple and very fast and achieves DNA extraction efficiencies similar to those obtained with a commercial kit. ddH 2 O double-distilled water, qPCR quantitative PCR.

Headspace single drop microextraction versus dispersive liquid-liquid microextraction using magnetic ionic liquid extraction solvents

A headspace single drop microextraction (HS-SDME) method and a dispersive liquid-liquid microextraction (DLLME) method were developed using two tetrachloromanganate ([MnCl₄^2-])-based magnetic ionic liquids (MIL) as extraction solvents for the determination of twelve aromatic compounds, including four polyaromatic hydrocarbons, by reversed phase high-performance liquid chromatography (HPLC). The analytical performance of the developed HS-SDME method was compared to the DLLME approach employing the same MILs. In the HS-SDME approach, the magnetic field generated by the magnet was exploited to suspend the MIL solvent from the tip of a rod magnet. The utilization of MILs in HS-SDME resulted in a highly stable microdroplet under elevated temperatures and long extraction times, overcoming a common challenge encountered in traditional SDME approaches of droplet instability. The low UV absorbance of the [MnCl₄^2-]-based MILs permitted direct analysis of the analyte enriched extraction solvent by HPLC. In HS-SDME, the effects of ionic strength of the sample solution, temperature of the extraction system, extraction time, stir rate, and headspace volume on extraction efficiencies were examined. Coefficients of determination (R²) ranged from 0.994 to 0.999 and limits of detection (LODs) varied from 0.04 to 1.0μgL^-1 with relative recoveries from lake water ranging from 70.2% to 109.6%. For the DLLME method, parameters including disperser solvent type and volume, ionic strength of the sample solution, mass of extraction solvent, and extraction time were studied and optimized. Coefficients of determination for the DLLME method varied from 0.997 to 0.999 with LODs ranging from 0.05 to 1.0μgL^-1. Relative recoveries from lake water samples ranged from 68.7% to 104.5%. Overall, the DLLME approach permitted faster extraction times and higher enrichment factors for analytes with low vapor pressure whereas the HS-SDME approach exhibited better extraction efficiencies for analytes with relatively higher vapor pressure.

Biological Activity of Ionic Liquids and Their Application in Pharmaceutics and Medicine

Ionic liquids are remarkable chemical compounds, which find applications in many areas of modern science. Because of their highly tunable nature and exceptional properties, ionic liquids have become essential players in the fields of synthesis and catalysis, extraction, electrochemistry, analytics, biotechnology, etc. Apart from physical and chemical features of ionic liquids, their high biological activity has been attracting significant attention from biochemists, ecologists, and medical scientists. This Review is dedicated to biological activities of ionic liquids, with a special emphasis on their potential employment in pharmaceutics and medicine. The accumulated data on the biological activity of ionic liquids, including their antimicrobial and cytotoxic properties, are discussed in view of possible applications in drug synthesis and drug delivery systems. Dedicated attention is given to a novel active pharmaceutical ingredient-ionic liquid (API-IL) concept, which suggests using traditional drugs in the form of ionic liquid species. The main aim of this Review is to attract a broad audience of chemical, biological, and medical scientists to study advantages of ionic liquid pharmaceutics. Overall, the discussed data highlight the importance of the research direction defined as "Ioliomics", studies of ions in liquids in modern chemistry, biology, and medicine.