Ionic liquids (ILs) have emerged as multifunctional compounds with low volatility, high thermal stability, and tunable solvation capabilities, making them highly promising for biomedical applications. First explored in the late 1990s and early 2000s for enhancing the thermal stability of enzymes, antimicrobial agents, and controlled release systems, ILs have since gained significant attention in drug delivery, antimicrobial treatments, medical imaging, and biosensing. This review examines the diverse functions of ILs in contemporary therapeutics and diagnostics, highlighting their transformative capabilities in improving drug solubility, bioavailability, transdermal permeability, and pathogen inactivation. In drug delivery, ILs improve solubility of bioactive compounds, with several IL formulations achieving substantial solubility enhancements for poorly soluble drugs. Bio-ILs, in particular, show promise in enhancing drug delivery systems, such as improving transdermal permeability. ILs also exhibit significant antimicrobial and antiviral activity, offering new avenues for combating resistant pathogens. Despite their broad potential, challenges such as cytotoxicity, long-term metabolic effects, and the stability of ILs in physiological conditions persist. While much research has focused on their physicochemical properties, biological activity and in vivo studies are still underexplored. The future directions for ILs in biomedical applications include the development of bioengineered ILs and hybrid ILs, combining functional components like nanoparticles and polymers to create multifunctional materials. These ILs, derived from renewable resources, show great promise in personalized medicine and clinical applications. Further research is necessary to evaluate their pharmacokinetics, biodistribution, and long-term safety to fully realize their biomedical potential. This study emphasizes the potential of ILs to transform therapeutic and diagnostic technologies by highlighting present shortcomings and offering pathways for clinical translation, while also debating the need for continuous research to fully utilize their biomedical capabilities.

Nanoemulsions, characterized by their nanosized particles ranging from 20 to 200 nm, are effective carriers for drug molecules. Our novel oil-in-water nanoemulsion, NE-FLO™, formulated from lemon and fish byproduct oils, demonstrates promising antioxidant and anti-inflammatory activities, with initial studies indicating nontoxicity to normal skin cells. This study investigated the safety of NE-FLO™ using brine shrimp (Artemia salina) and zebrafish (Danio rerio) models, focusing on concentration-dependent effects and LC₅₀ values. At lower concentrations (0.1 mg·L⁻¹, 0.01 mg·L⁻¹, and 0.001 mg·L⁻¹), NE-FLO™ showed minimal toxicity without adverse effects. However, at 1 mg·L⁻¹, reduced survival rates indicate potential toxicity. Specifically, this concentration also induces altered swimming behaviors in zebrafish. LC₅₀ values are 8.7474 mg·L⁻¹ for brine shrimp and 0.316 mg·L⁻¹ for adult zebrafish. These results underscore the necessity for further detailed investigations into NE-FLO™, balancing its therapeutic benefits with potential toxicity risks. This study emphasizes the importance of optimizing nanoemulsion formulations from fish oil and conducting comprehensive safety assessments to meet regulatory standards.

Plant-parasitic nematodes (PPNs), particularly Meloidogyne enterolobii, pose a severe threat to global agriculture, necessitating the development of sustainable and highly effective management alternatives. Herein, we report the rational design, physicochemical characterisation, and nematicidal evaluation of lemon oil-loaded ionic liquid nanoemulsions. Three distinct ionic liquids (ILs)—1,3-dimethylimidazolium acetate ([DMIM][OAc]), 1,3-dimethylimidazolium chloride ([DMIM][Cl]), and 1-methylimidazolium acetate ([MIM][OAc])—were integrated into oil-in-water nanoemulsions to assess their structural influence on formulation stability and bioactivity. The formulated ionic liquid nanoemulsions (IL-NEs) exhibited excellent colloidal properties, characterised by monodisperse nanometric droplets (18.13–24.42 nm, polydispersity index (PDI) < 0.4) and stable pH profiles with no visible phase separation over 120 days under the tested storage conditions. In vitro bioassays against M. enterolobii revealed a distinct structure–activity relationship (SAR) driven by the IL cation-anion composition, alongside strong concentration- and time-dependent efficacy. The [MIM][OAc]-based formulation demonstrated superior nematicidal performance, achieving the lowest terminal LC₅₀ (0.23% at 20 h) and the most rapid mortality kinetics (LT₅₀ of 7.63 h at 5.0%). Microscopic observations revealed marked morphological alterations, including internal structural damage and disruption of the integument. These findings unequivocally highlight the potential of structurally tunable IL-NEs as a potent, sustainable delivery platform for essential oil-based biopesticides in modern crop protection.

Food preservation is essential for maintaining product quality, safety, and shelf life. Ionic liquids (ILs) have emerged as promising alternatives to traditional preservatives due to their tunable physicochemical properties, allowing compatibility with diverse food matrices without compromising flavor, texture, or nutritional value. However, identifying IL systems that balance antimicrobial efficacy and food quality remains challenging. Computational screening using COSMO‐RS offers a predictive approach to evaluate IL‐solute interactions without extensive experimental trials. In this study, 40 ILs were systematically assessed for their interactions with L‐Arginine (Arg). Tetramethylammonium [TeMA] and Triethylammonium [TEA] cations exhibited reduced steric hindrance, promoting stronger association with Arg. Among the anions, carbonate (CO ₃ ^{2 −} ) and acetate (OAc ⁻ ) formed strong hydrogen bonding networks with Arg. The ILs [TEA][CO ₃ ^{2 −} ] and [TeMA][CO ₃ ^{2 −} ] showed the strongest affinity toward bacterial cell wall components, including N ‐Acetylmuramic acid (MurNAc), N ‐Acetyl‐D‐glucosamine (GlcNAc), and N ‐Acetylneuraminic acid (NANA), suggesting disruption of the peptidoglycan layer. The effect of water content was evaluated across varying water mole fractions to simulate moisture‐rich, spoilage‐prone food matrices. At low to intermediate hydration levels, [TeMA][CO ₃ ^{2 −} ] showed greater resistance to hydration‐induced Arg loss than [TEA][CO ₃ ^{2 −} ], indicating better retention of antimicrobial functionality. These findings support the potential of IL‐Arg systems as effective and safe next‐generation food preservatives.