Potentials of ionic liquids to overcome physical and biological barriers

Bioactive Glycyrrhizic Acid Ionic Liquid Self-Assembled Nanomicelles for Enhanced Transdermal Delivery of Anti-Photoaging Signal Peptides

Sigal peptides have garnered remarkable efficacy in rejuvenating photoaged skin and delaying senescence. Nevertheless, their low solubility and poor permeability bring about a formidable challenge in their transdermal delivery. To address this challenge, bioactive ionic liquids (ILs) synthesized from natural glycyrrhizic acid (GA) and oxymatrine (OMT) with eminent biocompatibility is first prepared. The components ratios and inherent forming mechanisms of GA-OMT (GAO) are optimized by molecular dynamics simulations and density functional theory calculations. Remarkably, GAO can significantly improve the sparingly soluble properties of palmitoyl pentapeptide-4 (PAL-4), a model peptide drug. Subsequently, GAO self-assembled micelles loading PAL-4 (GAO/PAL-4-SM) are fabricated without additional auxiliary materials. The permeation and subcutaneous retention of PAL-4 are significantly promoted with 10wt.% GAO-SM. Moreover, GAO ILs facilitated PAL-4 permeation by enhancing its miscibility and interaction with stratum corneum (SC), offering a pulling effect and micellar structures for PAL-4, as elucidated by computational simulations. In cellular and animal photoaging experiments, GAO/PAL-4-SM possessed remarkable capabilities in boosting collagen and hyaluronic acid regeneration, mitigating inflammation and apoptosis, accelerating macrophage M2 polarization, thereby lessening skin wrinkles and leveraging elasticity. Collectively, the research innovatively designed an ILs self-assembled nano-micellar transdermal delivery system to enhance the permeability and anti-photoaging effect of signal peptides.

A shielded cascade of targeted nanocarriers spanning multiple microenvironmental barriers for inflammatory disease therapy

BACKGROUND

The multi-biological barriers present in the inflammatory microenvironment severely limit the targeted aggregation of anti-inflammatory drugs in the lesion area. However, conventional responsive drug carriers inevitably come into contact with several pro-responsive stimulatory mediators simultaneously, leading to premature drug release and loss of most therapeutic effects. Breaking through the multi-level barriers of the inflammatory microenvironment is essential to improve the enrichment and bioavailability of drugs.

RESULTS

In this study, we propose a novel two-stage structural strategy to build shielded cascades of targeted nanocarriers (FA-PTP@Que) through inflammatory mediators, using cascade structures to cross multiple environmental barriers. The cascade structure of FA-PTP@Que is responsive to inflammatory mediators and exhibits ideal pathological microenvironmental response and drug release properties. FA-PTP@Que has shown good macrophage regulation and anti-inflammatory effects by efficiently targeting macrophages, scavenging intracellular reactive oxygen species (ROS), and down-regulating the secretion of pro-inflammatory factors. Significantly, in mice with arthritis and colitis, FA-PTP@Que enriches and targets macrophages at the sites of arthritis and colitis, showing significant anti-inflammatory effects.

CONCLUSION

FA-PTP@Que combines active chemotaxis of nanocarriers to inflammatory tissues and active targeting of effector cells, acting precisely at each barrier level in different microenvironments by responding to inflammatory mediators and overcoming the multiple barriers in the inflammatory microenvironment. This innovative strategy can effectively break through various inflammatory microenvironments and has the potential application to other inflammatory diseases.

The molecular design of novel phospholipid-inspired ionic liquid transdermal penetration enhancers: Innovative insights on the action mode and mechanism

Ionic liquid transdermal penetration enhancers (IL@TPEs) as new enhancement methods have significant advantages in the transdermal drug delivery system. However, the scientific frameworks for the design of efficient IL@TPEs and their applications in transdermal formulations were still lack. So, a series of novel biomimetic phospholipid-inspired IL@TPEs (PIL@TPEs) were designed and synthesized. The developed QSARs proved that enhancement efficacy of PIL@TPEs depended on pKa of drugs and M.W., Polar., and pKa of cations. Surprisingly, the PIL@TPEs dissociated during transdermal process, and skin penetration amounts of acidic drugs was inversely proportional to skin retention amounts of cations, which showed that action modes of PIL@TPEs were different from conventional enhancers. The novel mechanisms of PIL@TPEs were elucidated by quantitative determination of dynamic interaction among cations, anions, drugs, and skins. The PIL@TPEs with high enhancement efficiency owned strong interactions with drugs determined by ATR-FTIR, Raman and NOESY. Moreover, the PIL@TPEs owning better stability in skin ensured the production of strong interactions with lipids and keratins characterized by ATR-FTIR, 1H NMR and CLSM. The good safety of optimized PIL@TPEs was proved by determining cytotoxicity, apoptosis, inflammatory cells, and cytokines. In conclusion, this project will make an important contribution to the design and application of IL@TPEs.

Combinatorial MD/QM studies to develop novel ionic liquid-based anticancer drug delivery systems with aminium derived from carbohydrates as cationic components

The main challenges in anticancer drug design include solubility in organic and aqueous phases, bioavailability, selective targeting of specific receptors, and low toxicity. Notably, solubility, bioavailability, and receptor-specific targeting are interconnected factors that significantly influence the therapeutic efficacy of anticancer drugs. The primary objective of this study is to design novel drug delivery systems based on ionic liquids. These systems incorporate structures such as N, N, N-trimethyl-2-(((2 S,3R,4 S,5 S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2 H-pyran-2-yl)oxy)ethan-1-aminium (GTA) and (2 S,3R,4 S,5 S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)-N, N, N-trimethyltetrahydro-2 H-pyran-2-aminium (NTPA) derived from carbohydrates as cationic components, with anticancer drugs acting as anions. The goal is to investigate the effects of these novel pharmaceutical active ionic liquids on the interactions between the drugs and cell membranes. Additionally, this study examines changes in the solubility of anticancer drugs in both organic and aqueous phases after their conversion into ionic liquids. Molecular dynamics simulations (MD) and quantum mechanics calculations (QM) are employed to achieve these objectives. Known anticancer-candidate ionic liquid, such as 3-(2-((4-fluorophenyl)amino)-2-oxoethyl)-1-methyl-1 H-imidazol-3-ium-tetrafluoroborate, is considered as a reference point in our investigations. Furthermore, we aim to assess whether the direct attachment of the aminium group to the saccharide portion of the cations or the indirect attachment through a choline group significantly impacts the final properties of the designed anticancer ionic liquids. Another aim of this study is to demonstrate that QM studies need to be complemented by MD studies to provide insights into the behaviors of ionic liquids. Initially, we calculate the binding energies between cations and anions of all the ionic liquids at the B3LYP/6-311 + + G(d, p) level of theory. Subsequently, molecular dynamics simulations using GROMACS 5.2 are employed to obtain more precise information about these understudied ionic liquids. A combination of density functional theory (DFT) calculations and a solvation model based on density (SMD) is utilized to determine the solubility of free anticancer drugs and our active anticancer ionic liquids in various phases. We validate our findings by evaluating the interactions between the formulated ionic liquids and cell membranes using the DPPC model through combined MD simulations and docking procedures.

Design Principles and Applications of Ionic Liquids for Transdermal Drug Delivery

Ionic liquids (ILs) are salts with melting points typically <100 °C, composed of specific anions and cations. Recently, IL application has expanded into material engineering and biomedicine. Due to their unique properties, ILs have garnered significant interest in pharmacological research as solubilizers, transdermal absorption enhancers, antibacterial agents, and stabilizers of insoluble pharmaceutical active ingredients. The improvement of skin permeability by ILs is closely associated with their specific physicochemical characteristics, which are identified by their ionic composition. However, the existing literature on transdermal medication administration is insufficient in terms of a comprehensive knowledge base. This review provides a comprehensive assessment of the design principles involved in IL synthesis. Additionally, it discusses the methods utilized to assess skin permeability and provides a focused outline of IL application in transdermal drug administration.

Choline geranate (CAGE): A multifaceted ionic liquid for drug delivery

Ionic liquids, organic salts in a liquid state below 100 °C, have traditionally been associated with industrial applications. Recent research has introduced a new generation of ionic liquids, designed from biocompatible ions, to enable applications in drug delivery. Here, I provide a historical perspective, development status and applications of a leading example of biocompatible ionic liquids, a salt of Choline And Geranic acid (CAGE). Since its first report in 2014, CAGE has opened multiple drug delivery applications including transdermal, oral, buccal, sustained release, tissue ablation, periodontitis and hand hygiene, among others. CAGE-based products have been tested in more than 200 patients through multiple Phase 1 and Phase 2 clinical studies, including successful use in a Phase 2 clinical study in Atopic Dermatitis patients. CAGE became the first 'drug delivery ionic liquid' to enter into clinical trials. This article summarizes the key fundamental and translational aspects of CAGE as pertained to its use in drug delivery.

Ionic liquid-based formulation approaches for enhanced transmucosal drug delivery

The utilization of ionic liquids (ILs) in pharmaceutical drug delivery applications has seen significant expansion in recent years, owing to their distinctive characteristics and inherent adjustability. These innovative compounds can be used to tackle challenges associated with traditional dosage forms, such as polymorphism, inadequate solubility, permeability, and efficacy in topical drug delivery systems. Here, we provide a brief classification of ILs, and their effectiveness in augmenting transmucosal drug delivery approaches by improving the solubility and permeability of active pharmaceutical ingredients (APIs) by temporary mucus modulation aiding the paracellular transport of APIs, prolonging drug retention, and, thus, aiding controlled drug release across various mucosal surfaces. We also highlight potential advances in, and future perspectives of, IL-based formulations in mucosal drug delivery.

Remotely Controlled Surface Charge Modulation of Magnetoelectric Nanogenerators for Swift and Efficient Drug Delivery

We have developed a highly efficient technique of magnetically controlled swift loading and release of doxorubicin (DOX) drug using a magnetoelectric nanogenerator (MENG). Core-shell nanostructured MENG with a magnetostrictive core and piezoelectric shell act as field-responsive nanocarriers and possess the capability of field-triggered drug release in a cancerous environment. MENGs generate a surface electric dipole when subjected to a magnetic field due to the strain-mediated magnetoelectric effect. The capability of directional magnetic field-assisted modulation of the surface electrical dipole of MENG provides a mechanism to create/break ionic bonds with DOX molecules, which facilitates efficient drug attachment and on-demand swift detachment of the drug at a targeted site. The magnetic field-assisted drug-loading mechanism was minutely analyzed using spectrophotometry and Raman spectroscopy. The detailed time-dependent analysis of controlled drug release by the MENG under unidirectional and rotating magnetic field excitation was conducted using field-emission scanning electron microscopy, energy-dispersive X-ray, and atomic force microscopic measurements. In vitro, experiments validate the cytocompatibility and magnetically assisted on-demand and swift DOX drug delivery by the MENG near MCF-7 breast cancer cells, which results in a significant enhancement of cancer cell killing efficiency. A state-of-the-art experiment was performed to visualize the nanoscale magnetoelectric effect of MENG using off-axis electron holography under Lorentz conditions.

Toward Clinical Applications: Transforming Nonantibiotic Antibacterials into Effective Next-Generation Supramolecular Therapeutics

Antibiotic resistance is a major driver of morbidity and mortality worldwide, necessitating alternatives. Due to their mechanism of action, bacteriophages, endolysins, and antimicrobial peptides (coined herein as nonantibiotic antibacterials, NAA) have risen to tackle this problem and led to paradigms in treating antibiotic-resistant bacterial infections. However, their clinical applications remain challenging and have been seriously hampered by cytotoxicity, instability, weak bioactivity, low on-target bioavailability, high pro-inflammatory responses, shorter half-life, and circulatory properties. Hence, to transit preclinical phases and beyond, it has become imperative to radically engineer these alternatives into innovative and revolutionary therapeutics to overcome recalcitrant infections. This perspective highlights the promise of these agents, their limitations, promising designs, nanotechnology, and delivery approaches that can be harnessed to transform these agents. Finally, I provide an outlook on the remaining challenges that need to be tackled for their widespread clinical administration.

Ionic Liquids in Pharmaceutical and Biomedical Applications: A Review

The unique properties of ionic liquids (ILs), such as structural tunability, good solubility, chemical/thermal stability, favorable biocompatibility, and simplicity of preparation, have led to a wide range of applications in the pharmaceutical and biomedical fields. ILs can not only speed up the chemical reaction process, improve the yield, and reduce environmental pollution but also improve many problems in the field of medicine, such as the poor drug solubility, product crystal instability, poor biological activity, and low drug delivery efficiency. This paper presents a systematic and concise analysis of the recent advancements and further applications of ILs in the pharmaceutical field from the aspects of drug synthesis, drug analysis, drug solubilization, and drug crystal engineering. Additionally, it explores the biomedical field, covering aspects such as drug carriers, stabilization of proteins, antimicrobials, and bioactive ionic liquids.