Novel biocompatible and self-buffering ionic liquids for biopharmaceutical applications

Do Ionic Liquids Exhibit the Required Characteristics to Dissolve, Extract, Stabilize, and Purify Proteins? Past-Present-Future Assessment

Proteins are highly labile molecules, thus requiring the presence of appropriate solvents and excipients in their liquid milieu to keep their stability and biological activity. In this field, ionic liquids (ILs) have gained momentum in the past years, with a relevant number of works reporting their successful use to dissolve, stabilize, extract, and purify proteins. Different approaches in protein-IL systems have been reported, namely, proteins dissolved in (i) neat ILs, (ii) ILs as co-solvents, (iii) ILs as adjuvants, (iv) ILs as surfactants, (v) ILs as phase-forming components of aqueous biphasic systems, and (vi) IL-polymer-protein/peptide conjugates. Herein, we critically analyze the works published to date and provide a comprehensive understanding of the IL-protein interactions affecting the stability, conformational alteration, unfolding, misfolding, and refolding of proteins while providing directions for future studies in view of imminent applications. Overall, it has been found that the stability or purification of proteins by ILs is bispecific and depends on the structure of both the IL and the protein. The most promising IL-protein systems are identified, which is valuable when foreseeing market applications of ILs, e.g., in "protein packaging" and "detergent applications". Future directions and other possibilities of IL-protein systems in light-harvesting and biotechnology/biomedical applications are discussed.

Good's Buffer Based Highly Biocompatible Ionic Liquid Modified PLGA Nanoparticles for the Selective Uptake in Cancer Cells

Achieving safe and efficacious drug delivery is still an outstanding challenge. Herein we have synthesized 20 biocompatible Good's buffer-based ionic liquids (GBILs) with a range of attractive properties for drug delivery applications. The synthesized GBILs were used to coat the surface of poly(lactic-co-glycolic acid) (PLGA) by nanoprecipitation-sonication and characterized by dynamic light scattering (DLS) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The GBIL-modified PLGA NPs were then tested for their interaction with bio-interfaces such as serum proteins (using SDS-PAGE and LCMS) and red blood cells (RBCs) isolated from human and BALB/c mouse blood. In this report, we show that surface modification of PLGA with certain GBILs led to modulation of preferential cellular uptake towards human triple-negative breast cancer cells (MDA-MB-231) compared to human normal healthy breast cells (MCF-10A). For example, cholinium N,N-bis(2-hydroxyethyl)-2-aminoethane sulfonate (CBES) coated PLGA NPs were found to be selective for MDA-MB-231 cells (60.7 ± 0.7 %) as compared to MCF-10A cells (27.3 ± 0.7 %). In this way, GBIL-coatings have increased PLGA NP uptake in the cancer cells by 2-fold while decreasing the uptake towards normal healthy breast cells. Therefore, GBIL-modified nanoparticles could be a versatile platform for targeted drug delivery and gene therapy applications, as their surface properties can be tailored to interact with specific cell receptors and enhance cellular uptake. This formulation technique has shown promising results for targeting specific cells, which could be explored further for other cell types to achieve site-specific and efficient delivery of therapeutic agents.

Can egg yolk antibodies terminate the CSBV infection in apiculture?

Chinese sacbrood virus (CSBV) is the most severe pathogen of Apis cerana, which leads to serious fatal diseases in bee colonies and eventual catastrophe for the Chinese beekeeping industry. Additionally, CSBV can potentially infect Apis mellifera by bridging the species barrier and significantly affect the productivity of the honey industry. Although several approaches, such as feeding royal jelly, traditional Chinese medicine, and double-stranded RNA treatments, have been employed to suppress CSBV infection, their practical applicabilities are constrained due to their poor effectiveness. In recent years, specific egg yolk antibodies (EYA) have been increasingly utilized in passive immunotherapy for infectious diseases without any side effects. According to both laboratory research and practical use, EYA have demonstrated superior protection for bees against CSBV infection. This review provided an in-depth analysis of the issues and drawbacks in this field in addition to provide a thorough summary of current advancements in CSBV studies. Some promising strategies for the synergistic study of EYA against CSBV, including the exploitation of novel antibody drugs, novel TCM monomer/formula determination, and development of nucleotide drugs, are also proposed in this review. Furthermore, the prospects for the future perspectives of EYA research and applications are presented. Collectively, EYA would terminate CSBV infection soon, as well as will provide scientific guidance and references to control and manage other viral infections in apiculture.

Synthesis and Characterization of Linear Copolymers Based on Pharmaceutically Functionalized Monomeric Choline Ionic Liquid for Delivery of p-Aminosalicylate

Bioactive linear poly(ionic liquid)s (PIL) were designed as carriers in drug delivery systems (DDS). Their synthesis was based on a monomeric ionic liquid (MIL) with a relevant pharmaceutical anion to create therapeutically functionalized monomers, which further can be used in the controlled atom transfer radical polymerization (ATRP). The presence of chloride counterions in the quaternary ammonium groups of choline MIL, e.g., [2-(methacryloyloxy)ethyl]trimethyl-ammonium chloride (ChMACl), was stimulated to undergo the anion exchange with p-aminosalicylate sodium salt (NaPAS) as the source of the pharmaceutical anion with antibacterial activity. The resultant [2-(methacryloyloxy)ethyl]trimethylammonium p-aminosalicylate (ChMAPAS) was copolymerized to attain the well-defined linear choline-based copolymers with various contents of PAS anions (24–42%), which were regulated by the initial ratio of ChMAPAS to MMA and conversion degree. The length of polymeric chains was evaluated by the total monomer conversion (31–66%) yielding degree of polymerization (DPn = 133–272). Depending on the polymer carrier composition, PAS anions were exchanged by 60–100% within 1 h, 80–100% within 4 h, and completely after 24 h by phosphate anions in PBS imitating a physiological fluid.

Combined Use of Ionic Liquid-Based Aqueous Biphasic Systems and Microfluidic Devices for the Detection of Prostate-Specific Antigen

Prostate cancer (PCa) is one of the cancer types that most affects males worldwide and is among the highest contributors to cancer mortality rates. Therefore, there is an urgent need to find strategies to improve the diagnosis of PCa. Microtechnologies have been gaining ground in biomedical devices, with microfluidics and lab-on-chip systems potentially revolutionizing medical diagnostics. In this paper, it is shown that prostate-specific antigen (PSA) can be detected through an immunoassay performed in a microbead-based microfluidic device after being extracted and purified from a serum sample through an aqueous biphasic system (ABS). Given their well-established status as ABS components for successful bioseparations, ionic liquids (ILs) and polymers were used in combination with buffered salts. Using both IL-based and polymer-based ABS, it was demonstrated that it is possible to detect PSA in non-physiological environments. It was concluded that the ABS that performed better in extracting the PSA from serum were those composed of tetrabutylammonium chloride ([N₄₄₄₄]Cl) and tetrabutylphosphonium bromide ([P₄₄₄₄]Br), both combined with phosphate buffer, and constituted by polyethylene glycol with a molecular weight of 1000 g/mol (PEG1000) with citrate buffer. In comparison with the assay with PSA prepared in phosphate-buffered saline (PBS) or human serum in which no ABS-mediated extraction was applied, assays attained lower limits of detection after IL-based ABS-mediated extraction. These results reinforce the potential of this method in future point-of-care (PoC) measurements.

Ionic-liquid-based approaches to improve biopharmaceuticals downstream processing and formulation

The emergence of biopharmaceuticals, including proteins, nucleic acids, peptides, and vaccines, revolutionized the medical field, contributing to significant advances in the prophylaxis and treatment of chronic and life-threatening diseases. However, biopharmaceuticals manufacturing involves a set of complex upstream and downstream processes, which considerably impact their cost. In particular, despite the efforts made in the last decades to improve the existing technologies, downstream processing still accounts for more than 80% of the total biopharmaceutical production cost. On the other hand, the formulation of biological products must ensure they maintain their therapeutic performance and long-term stability, while preserving their physical and chemical structure. Ionic-liquid (IL)-based approaches arose as a promise alternative, showing the potential to be used in downstream processing to provide increased purity and recovery yield, as well as excipients for the development of stable biopharmaceutical formulations. This manuscript reviews the most important progress achieved in both fields. The work developed is critically discussed and complemented with a SWOT analysis.

Dual-Drug Delivery via the Self-Assembled Conjugates of Choline-Functionalized Graft Copolymers

Graft copolymers based on a choline ionic liquid (IL), [2-(methacryloyloxy)ethyl]-trimethylammonium chloride (TMAMA), were obtained by atom transfer radical polymerization. The presence of chloride counterions in the trimethylammonium groups promoted anion exchange to introduce fusidate anions (FUS, 32−55 mol.%) as the pharmaceutical anions. Both the choline-based IL copolymers and their ionic drug-carrier conjugates (FUS systems as the first type, 26−208 nm) formed micellar structures (CMC = 0.011−0.025 mg/mL). The amphiphilic systems were advantageous for the encapsulation of rifampicin (RIF, 40−67 mol.%), a well-known antibiotic, resulting in single-drug (RIF systems as the second type, 40−95 nm) and dual-drug systems (FUS/RIF as the third type, 31−65 nm). The obtained systems released significant amounts of drugs (FUS > RIF), which could be adjusted by the content of ionic units and the length of the copolymer side chains. The dual-drug systems released 31−55% FUS (4.3−5.6 μg/mL) and 19−31% RIF (3.3−4.0 μg/mL), and these results were slightly lower than those for the single-drug systems, reaching 45−81% for FUS (3.8−8.2 μg/mL) and 20−37% for RIF (3.4−4.0 μg/mL). The designed polymer systems show potential as co-delivery systems for combined therapy against drug-resistant strains using two drugs in one formula instead of the separate delivery of two drugs.

Protein aggregation and crystallization with ionic liquids: Insights into the influence of solvent properties

Ionic liquids (ILs) have been used in solvents for proteins in many applications, including biotechnology, pharmaceutics, and medicine due to their tunable physicochemical and biological properties. Protein aggregation is often undesirable, and predominantly occurs during bioprocesses, while the aggregation process can be reversible or irreversible and the aggregates formed can be native/non-native and soluble/insoluble. Recent studies have clearly identified key properties of ILs and IL-water mixtures related to protein performance, suggesting the use of the tailorable properties of ILs to inhibit protein aggregation, to promote protein crystallization, and to control protein aggregation pathways. This review discusses the critical properties of IL and IL-water mixtures and presents the latest understanding of the protein aggregation pathways and the development of IL systems that affect or control the protein aggregation process. Through this feature article, we hope to inspire further advances in understanding and new approaches to controlling protein behavior to optimize bioprocesses.

Protic Ionic Liquid Cation Alkyl Chain Length Effect on Lysozyme Structure

Solvents that stabilize protein structures can improve and expand their biochemical applications, particularly with the growing interest in biocatalytic-based processes. Aiming to select novel solvents for protein stabilization, we explored the effect of alkylammonium nitrate protic ionic liquids (PILs)-water mixtures with increasing cation alkyl chain length on lysozyme conformational stability. Four PILs were studied, that is, ethylammonium nitrate (EAN), butylammonium nitrate (BAN), hexylammonium nitrate (HAN), and octylammonium nitrate (OAN). The surface tension, viscosity, and density of PIL-water mixtures at low to high concentrations were firstly determined, which showed that an increasing cation alkyl chain length caused a decrease in the surface tension and density as well as an increase in viscosity for all PIL solutions. Small-angle X-ray scattering (SAXS) was used to investigate the liquid nanostructure of the PIL solutions, as well as the overall size, conformational flexibility and changes to lysozyme structure. The concentrated PILs with longer alkyl chain lengths, i.e., over 10 mol% butyl-, 5 mol% hexyl- and 1 mol% octylammonium cations, possessed liquid nanostructures. This detrimentally interfered with solvent subtraction, and the more structured PIL solutions prevented quantitative SAXS analysis of lysozyme structure. The radius of gyration (R_g) of lysozyme in the less structured aqueous PIL solutions showed little change with up to 10 mol% of PIL. Kratky plots, SREFLEX models, and FTIR data showed that the protein conformation was maintained at a low PIL concentration of 1 mol% and lower when compared with the buffer solution. However, 50 mol% EAN and 5 mol% HAN significantly increased the R_g of lysozyme, indicating unfolding and aggregation of lysozyme. The hydrophobic interaction and liquid nanostructure resulting from the increased cation alkyl chain length in HAN likely becomes critical. The impact of HAN and OAN, particularly at high concentrations, on lysozyme structure was further revealed by FTIR. This work highlights the negative effect of a long alkyl chain length and high concentration of PILs on lysozyme structural stability.

Ionic Liquid-Based Materials for Biomedical Applications

Ionic liquids (ILs) have been extensively explored and implemented in different areas, ranging from sensors and actuators to the biomedical field. The increasing attention devoted to ILs centers on their unique properties and possible combination of different cations and anions, allowing the development of materials with specific functionalities and requirements for applications. Particularly for biomedical applications, ILs have been used for biomaterials preparation, improving dissolution and processability, and have been combined with natural and synthetic polymer matrixes to develop IL-polymer hybrid materials to be employed in different fields of the biomedical area. This review focus on recent advances concerning the role of ILs in the development of biomaterials and their combination with natural and synthetic polymers for different biomedical areas, including drug delivery, cancer therapy, tissue engineering, antimicrobial and antifungal agents, and biosensing.

Molecular Dynamics Evaluation of the Effect of Cholinium Phenylalaninate Biocompatible Ionic Liquid on Biomimetic Membranes

Toward the search of sustainable green solvents, choline amino acid ([Ch][AA]) ionic liquids (ILs), mainly derived from renewable feedstocks, have emerged as a promising atoxic alternative to the conventional solvents. Recent studies have shown the remarkably benign nature of cholinium-based ILs against biomimetic phospholipid membranes. However, few of the contemporaneous experimental studies have contradicted the aforesaid ecofriendly nature of these ILs with anions comprising longer alkyl or aromatic tails. Aiming to understand the influence of amino acid side-chain variation in a particular bio-IL on biomembranes, herein, we have evaluated the effect of cholinium phenylalaninate ([Ch][Phe]) IL on the structural stability of homogeneous biomimetic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) lipid bilayers using atomistic molecular dynamics simulations. Although we observe spontaneous intercalation of aromatic rings of [Phe]^- anions in the hydrophobic region of the bilayers, the polar backbone of the anion remains coordinated with the lipid polar part through strong electrostatic and H-bonding interactions. Besides, the [Ch]⁺ cations get accumulated at the lipid-water interface to counter the excess negative charge density. The intercalation of the anionic rings causes significant perturbations in the lipid structural arrangement while still maintaining the bilayer integrity. The quantitative evaluation to probe the deteriorating effect of this bio-IL application establishes anions as the principal component causing the observed structural perturbations. The analysis of the structural properties along with the free energy assessment reveals the higher efficacy of [Ch][Phe] bio-IL to perturb the POPE bilayer structure than the POPC bilayer.

Building on Surface-Active Ionic Liquids for the Rescuing of the Antimalarial Drug Chloroquine

Ionic liquids derived from classical antimalarials are emerging as a new approach towards the cost-effective rescuing of those drugs. Herein, we disclose novel surface-active ionic liquids derived from chloroquine and natural fatty acids whose antimalarial activity in vitro was found to be superior to that of the parent drug. The most potent ionic liquid was the laurate salt of chloroquine, which presented IC₅₀ values of 4 and 110 nM against a chloroquine-sensitive and a chloroquine-resistant strain of Plasmodium falciparum, respectively, corresponding to an 11- and 6-fold increase in potency as compared to the reference chloroquine bisphosphate salt against the same strains. This unprecedented report opens new perspectives in both the fields of malaria chemotherapy and of surface-active ionic liquids derived from active pharmaceutical ingredients.

Green chemical engineering in China

In China, the rapid development greatly promotes the national economic power and living standard but also inevitably brings a series of environmental problems. In order to resolve these problems fundamentally, Chinese scientists have been undertaking research in the area of green chemical engineering (GCE) for many years and achieved great progresses. In this paper, we reviewed the research progresses related to GCE in China and screened four typical topics related to the Chinese resources characteristics and environmental requirements, i.e. ionic liquids and their applications, biomass utilization and bio-based materials/products, green solvent-mediated extraction technologies, and cold plasmas for coal conversion. Afterwards, the perspectives and development tendencies of GCE were proposed, and the challenges which will be faced while developing available industrial technologies in China were mentioned.

Solvatochromism as a new tool to distinguish structurally similar compounds

It is here reported a new concept based on solvatochromism to distinguish structurally similar compounds in aqueous solutions by the analysis of the stabilization of electronic excited states. The sensitivity of this approach to differentiate similar organic compounds, such as structural isomers or compound differing in the number of methylene groups, or proteins with conformational changes induced by being or not bound to cofactors, differing in two amino acids substitutions, or differing in their glycosylation profile, is demonstrated. The sensitivity of the proposed approach, based on the solvatochromic method, opens the path to its use as an auxiliary analytical tool in biomedical diagnosis/prognosis or in quality control of biologic-based drugs.

Biocompatible ionic liquids: fundamental behaviours and applications

The bio- and eco-friendly nature of biocompatible ionic liquids contributes to their widespread use in a wide range of fields.

Cholinium-based Good's buffers ionic liquids as remarkable stabilizers and recyclable preservation media for recombinant small RNAs

RNA is a biopolymer of high relevance in the biopharmaceuticals field and in fundamental and applied research; however, the preservation of the RNA stability is still a remarkable challenge. Herein, we demonstrate the enhanced potential of aqueous solutions of self-buffering cholinium-based Good's buffers ionic liquids (GB-ILs), at 20 and 50 % (w/w), as alternative preservation media of recombinant small RNAs. The thermal stability of RNA is highly enhanced by GB-ILs, with an increase of 14 °C in the biopolymer melting temperature - the highest increase observed up to date with ILs. Most GB-ILs investigated improve the stability of RNA at least up to 30-days, both at 25 °C and at 4 °C, without requiring the typical samples freezing. Molecular dynamics simulations were applied to better understand the molecular-level mechanisms responsible for the observed RNA improved stability. The number of IL cations surrounding the RNA chain is similar, yet with differences found for the IL anions, which are responsible for the overall charge of the biopolymer first solvation sphere. No cytotoxicity of the studied solutions containing RNA and ILs at 20 % (w/w) was observed onto two distinct human cell lines, reinforcing their potential to act as preservation media when foreseeing biopharmaceutical applications. Finally, RNA was successfully recovered from the ILs aqueous solutions, without changes in its structural integrity, and the ILs successfully recycled and reused.

Probing spatial locality in ionic liquids with the grand canonical adaptive resolution molecular dynamics technique

We employ the Grand Canonical Adaptive Resolution Simulation (GC-AdResS) molecular dynamics technique to test the spatial locality of the 1-ethyl 3-methyl imidazolium chloride liquid. In GC-AdResS, atomistic details are kept only in an open sub-region of the system while the environment is treated at coarse-grained level; thus, if spatial quantities calculated in such a sub-region agree with the equivalent quantities calculated in a full atomistic simulation, then the atomistic degrees of freedom outside the sub-region play a negligible role. The size of the sub-region fixes the degree of spatial locality of a certain quantity. We show that even for sub-regions whose radius corresponds to the size of a few molecules, spatial properties are reasonably reproduced thus suggesting a higher degree of spatial locality, a hypothesis put forward also by other researchers and that seems to play an important role for the characterization of fundamental properties of a large class of ionic liquids.

Separation of immunoglobulin G using aqueous biphasic systems composed of cholinium-based ionic liquids and poly(propylene glycol)

BACKGROUND

The use of antibodies, such as immunoglobulin G (IgG), has faced a significant growth in the past decades for biomedical and research purposes. However, antibodies are high cost biopharmaceuticals, for which the development of alternative and cost-effective purification strategies is still in high demand.

RESULTS

Aqueous biphasic systems (ABS) composed of poly(propylene glycol) (PPG) and cholinium-based ionic liquids (ILs) were investigated for the separation of IgG. The ABS phase diagrams were determined and characterized whenever required. Initial optimization studies with commercial IgG were carried out, followed by the extraction of IgG from rabbit serum. In all ABS, IgG preferentially partitions to the IL-rich phase, unveiling preferential interactions between IgG and ILs. Good results were obtained with commercial IgG, with extraction efficiencies ranging between 93% and 100%, and recovery yields ranging between 20% and 100%. Two of the best and two of the worst identified ABS were then evaluated in what concerns their performance to separate and recover IgG from rabbit serum. With these ABS, extraction efficiencies of 100% and recovery yields > 80% were obtained, indicating an increase in the recovery yield and extraction efficiencies when using real matrices. Under the best conditions studied, IgG with a purity level of 49% was obtained in a single-step. This purity level of IgG is higher than those previously reported using other IL-polymer ABS.

CONCLUSION

IgG preferentially migrates to the IL-rich phase in ABS formed by ILs and polymers, allowing the design of effective separation systems for its recovery from serum samples.

Ionic liquids as biocompatible stabilizers of proteins

Ionic liquids (ILs) have recently emerged as versatile solvents and additives in the field of biotechnology, particularly as stabilizers of proteins and enzymes. Of interest to the biotechnology industry is the formulation of stable biopharmaceuticals, therapeutic proteins, and vaccines which have revolutionized the treatment of many diseases including debilitating conditions such as cancers and auto-immune diseases. The stabilization of therapeutic proteins is typically achieved using additives that prevent unfolding and aggregation of these proteins during manufacture, transport, and long-term storage. To determine if ILs could be used in the formulation of stable therapeutic proteins, a thorough understanding of the effects of ILs on protein stability is needed, as well as understanding the toxicity of ILs on humans, and other considerations for formulation development such as viscosity and osmolality. In this review, we summarize recent developments on the stabilization of proteins and enzymes using ILs, with emphasis on identifying biocompatible ILs that may be suitable for the formulation of stable biopharmaceuticals in the future.

Ionic Liquids Treated within the Grand Canonical Adaptive Resolution Molecular Dynamics Technique

We use the Grand Canonical Adaptive Resolution Molecular Dynamics Technique (GC-AdResS) to examine the essential degrees of freedom necessary for reproducing the structural properties of the imidazolium class of ionic liquids. In this technique, the atomistic details are treated as an open sub-region of the system while the surrounding environment is modelled as a generic coarse-grained model. We systematically characterize the spatial quantities such as intramolecular, intermolecular radial distribution functions, other structural and orientational properties of ILs. The spatial quantities computed in an open sub-region of the system are in excellent agreement with the equivalent quantities calculated in a full atomistic simulation, suggesting that the atomistic degrees of freedom outside the sub-region are negligible. The size of the sub-region considered in this study is 2 nm, which is essentially the size of a few ions. Insight from the study suggests that a higher degree of spatial locality seems to play a crucial role in characterizing the properties of imidazolium based ionic liquids.

New ionic liquids based on systemic acquired resistance inducers combined with the phytotoxicity reducing cholinium cation

Systemic acquired resistance (SAR) is one of the most promising ways to support plants in the fight against viruses.

Good's Buffer Ionic Liquids as Relevant Phase-Forming Components of Self-Buffered Aqueous Biphasic Systems

A series of new self-buffering ionic liquids (ILs) based on Good's buffers (GBs) anions and the tetrabutylphosphonium cation ([P₄₄₄₄]⁺) was here synthesized and characterized. The self-buffering behaviour of the GB-ILs was confirmed by measuring their protonation constants by potentiometry. Further, their ability to form aqueous biphasic systems with the biodegradable potassium citrate salt was evaluated, and further investigated for the extraction of proteins, using bovine serum albumin (BSA) as a model protein. If these ionic structures display self-buffering characteristics as well as a low toxicity towards the luminescent bacteria Vibrio fischeri, they were additionally found to be highly effective in the formation of ABS and in the extraction of BSA - extraction efficiencies of 100% to the IL-rich phase obtained in a single-step. The BSA secondary structure in the aqueous IL-rich solutions was evaluated through infrared spectroscopic studies revealing the protein-friendly nature of the synthesized ILs. Dynamic light scattering (DLS), "COnductor-like Screening MOdel for Real Solvents" (COSMO-RS), and molecular docking studies were finally carried out to better understand the main driving forces of the extraction process. The results suggest that van der Waals and hydrogen-bonding interactions are important driving forces of the protein migration towards the GB-IL-rich phase, while the molecular docking investigations demonstrated a stabilizing effect of the studied ILs over the protein.

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.

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.