BACKGROUND: A novel supported liquid extraction approach using small polymeric nanofibrous discs was demonstrated and applied to the analysis of real river water. Nanofibrous discs were tested to extract model mixture of 9 common water contaminants 4-nitrophenol, various chlorophenols, bisphenol A, permethrin, and fenoxycarb featuring a wide range of log P values (1.9-6.5). Polyacrylonitrile, polyhydroxybutyrate, and polylactic acid nanofibers were selected as adsorptive materials. One-step desorption was performed directly in HPLC vials, to avoid time-consuming evaporation and reconstitution steps. The discs were allowed to sediment to the bottom of the vial before injection into the chromatographic system. RESULTS: Various parameters affecting the extraction efficiency including 1-octanol volume, extraction time, ionic strength, and sample volume were investigated and optimized. Wetting the nanofiber discs with 1-octanol resulted in up to 20-fold increase in enrichment factor when compared to non-wetted polymer counterparts. The highest enrichment factors were observed for analytes with a log P range of 3.3-4.5. Our developed method showed good linearity in the range 20-200 μg/L for all analytes tested. Satisfactory repeatability with RSD <13 % were achieved covering all steps including disc preparation, wetting, extraction/elution, and chromatography analysis, and recoveries ranged from 58.93 to 121.43 %. SIGNIFICANCE: This work represents novel simple supported liquid extraction approach using impregnated polymer nanofiber discs. Using only 50 μL 1-octanol, we reduced the organic solvent compared to other extraction methods. There was no need for any plastic cartridge to hold the sorbent and direct in-vial desorption reduced the unnecessary, time-consuming steps and simplified the sample preparation protocol.
- Publication type
- Journal Article MeSH
Ionic liquids (ILs) have great potential to facilitate transdermal and topical drug delivery. Here, we investigated the mechanism of action of amphiphilic ILs 1-methyl-3-octylimidazolium bromide (C8MIM) and 3-dodecyl-1-methylimidazolium bromide (C12MIM) in skin barrier lipid models in comparison to their complex effects in human skin. C8MIM incorporated in a skin lipid model was a better permeation enhancer than C12MIM for water and model drugs, theophylline and diclofenac. Solid state 2H NMR and X-ray diffraction indicated that both ILs prefer the cholesterol-rich regions in skin lipids without significantly perturbing their lamellar arrangement and that C8MIM induces the formation of an isotropic lipid phase to a greater extent compared to C12MIM. C12MIM applied topically to the lipid model or human skin as a pretreatment was more potent than C8MIM. When co-applied with the drugs to human skin, aqueous C12MIM was more potent than C8MIM in enhancing theophylline permeation, but neither IL affected (even decreased) diclofenac permeation. Thus, the IL's ability to permeabilize skin lipid barrier is strongly modulated by its ability to reach the site of action and its interactions with drug and solvent. Such an interplay is far from trivial and requires detailed investigation to realize the full potential of ILs.
- MeSH
- Administration, Cutaneous MeSH
- Diclofenac pharmacology MeSH
- Ionic Liquids * pharmacology chemistry MeSH
- Humans MeSH
- Lipids MeSH
- Theophylline pharmacology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
The present work reviews the liquid antisolvent crystallization (LASC) to prepare the nanoparticle of pharmaceutical compounds to enhance their solubility, dissolution rate, and bioavailability. The application of ultrasound and additives is discussed to prepare the particles with narrow size distribution. The use of ionic liquid as an alternative to conventional organic solvent is presented. Herbal compounds, also known for low aqueous solubility and limited clinical application, have been crystalized by LASC and discussed here. The particle characteristics such as particle size and particle size distribution are interpreted in terms of supersaturation, nucleation, and growth phenomena. To overcome the disadvantage of batch crystallization, the scientific literature on continuous flow reactors is also reviewed. LASC in a microfluidic device is emerging as a promising technique. The different design of the microfluidic device and their application in LASC are discussed. The combination of the LASC technique with traditional techniques such as high-pressure homogenization and spray drying is presented. A comparison of product characteristics prepared by LASC and the supercritical CO2 antisolvent method is discussed to show that LASC is an attractive and inexpensive alternative for nanoparticle preparation. One of the major strengths of this paper is a discussion on less-explored applications of LASC in pharmaceutical research to attract the attention of future researchers.
Enterococcus faecalis is an important factor in nosocomial infections. The aim of this study was the isolation of the pathogenic genes of Enterococcus faecalis in mouth infection and the study of the expression of these genes by real-time PCR. In this study, 60 isolates of E. faecalis were isolated from oral infections. The presence and frequency of cyl, hyl, and esp genes and their expression by ionic liquid were evaluated using real-time PCR. MIC was determined by broth dilution method and biofilm production was measured, then biofilm inhibition ability and cytotoxicity test were performed by MTT method. The esp, cyl, and hyl genes were observed in 10, 11, and 2 isolates, respectively. cyl gene with the highest frequency of expression in the treated group was reduced by 1.14% under the influence of ionic liquid with methionine base. The results of MIC and Sub MIC concentrations were obtained with the effect of ionic liquid including 125 and 225 μg/mL, respectively. Amino-acid-based ionic liquids can also reduce biofilm production at sub-MIC concentrations (P < 0.05), and changes in cytotoxicity at different concentrations and over time are significant (P-value < 0.001). E. faecalis strains are genetically diverse and this indicates the polyclonal prevalence of strains in clinical specimens. Combination treatment of ionic liquid with common antimicrobial drugs has good antibacterial effects against Enterococcus species, and ionic liquid with a minimum dose can be a good alternative to single-drug treatment of Enterococcus infections.
- MeSH
- Amino Acids MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Biofilms MeSH
- Enterococcus faecalis MeSH
- Gram-Positive Bacterial Infections * drug therapy microbiology MeSH
- Ionic Liquids * pharmacology MeSH
- Real-Time Polymerase Chain Reaction MeSH
- Humans MeSH
- Methionine genetics pharmacology MeSH
- Microbial Sensitivity Tests MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
The morphology, composition, and selectivity of a silica-based monolithic stationary phase, grafted by a layer of trioctyl(3/4-vinylbenzyl)phosphonium chloride ([P888VBn]Cl), is presented. The results of elemental analysis confirmed that the prepared stationary phase contains 38.8 at.% of silicon, 60.2 at.% of carbon, and 1.0 at.% of phosphorus. Capillary columns (150 × 0.1 mm) for liquid chromatography were evaluated using alkylbenzenes, monosubstituted benzenes, polyaromatic compounds, substituted benzene regioisomers, and aromatic carboxylic and amino acids. The prepared ionic liquid (IL)-based stationary phase exhibits hydrophobic, hydrophilic, and electrostatic interactions, as confirmed by experiments on the evaluation of the effect of the mobile phase composition (content of acetonitrile and ammonium formate) on the isocratic chromatographic separation. Thus, the IL-based capillary column demonstrates a unique separation selectivity compared to Phenyl-, C8-, and C18-stationary phases, and high efficiency for an expanding number of structurally diverse compounds.
The effect of aqueous solutions of selected ionic liquids solutions on Ideonella sakaiensis PETase with bis(2-hydroxyethyl) terephthalate (BHET) substrate were studied by means of molecular dynamics simulations in order to identify the possible effect of ionic liquids on the structure and dynamics of enzymatic Polyethylene terephthalate (PET) hydrolysis. The use of specific ionic liquids can potentially enhance the enzymatic hydrolyses of PET where these ionic liquids are known to partially dissolve PET. The aqueous solution of cholinium phosphate were found to have the smallest effect of the structure of PETase, and its interaction with (BHET) as substrate was comparable to that with the pure water. Thus, the cholinium phosphate was identified as possible candidate as ionic liquid co-solvent to study the enzymatic hydrolyses of PET.
- MeSH
- Burkholderiales enzymology MeSH
- Hydrophobic and Hydrophilic Interactions MeSH
- Hydrolases metabolism MeSH
- Hydrolysis MeSH
- Ionic Liquids chemistry MeSH
- Protein Conformation MeSH
- Phthalic Acids chemistry MeSH
- Polyethylene Terephthalates chemistry MeSH
- Solvents chemistry MeSH
- Molecular Dynamics Simulation MeSH
- Hydrogen Bonding MeSH
- Publication type
- Journal Article MeSH
Volatile solvents are excellent extraction media for liquid-liquid extractions. However, their use in supported liquid membranes (SLMs) is limited by their evaporation from SLM and thus poor SLM stability and they have never been considered truly useful for electromembrane extraction (EME). In this contribution, volatile solvents were systematically investigated as liquid membranes for EME and their extraction characteristics were comprehensively examined for the first time. A short plug of a water immiscible volatile solvent (a free liquid membrane (FLM)) was sandwiched between two aqueous plugs (donor and acceptor solutions) in a narrow-bore polymeric tubing. Evaporation of the volatile FLM was thus completely avoided and excellent stability of the phase interface was ensured. Suitability of volatile FLMs for EMEs was justified by μ-EMEs of nortriptyline, haloperidol, loperamide and papaverine as model non-polar basic drugs. Extraction performance of μ-EME through ethyl acetate was comparable or better to that through standard non-volatile EME solvents and a high extraction selectivity was achieved for nortriptyline and haloperidol extracted through chloroform. μ-EMEs through the volatile FLMs were characterized by high extraction recoveries (62%-99% for standards and 40-89% for body fluids), low electric currents (10-1380 nA), no susceptibility to matrix ions and suitability for pretreatment of raw body fluids (human urine and serum). Resulting extracts were analysed by capillary electrophoresis with ultraviolet detection (CE/UV). Repeatability of the μ-EME-CE/UV method was excellent with intra-day and inter-day RSD values 0.8-3.2% and 1.8-4.6%, respectively. Further experiments demonstrated additional advantages of volatile FLMs by nearly exhaustive μ-EMEs of atenolol as the polar basic drug with no need for FLM modification by ionic carriers. The presented comprehensive examination of volatile solvents has broadened the range of liquid membranes suitable for EME and it is believed that this proof-of-concept study will stimulate further interest in a deeper investigation of volatile phase interfaces in EME.
- MeSH
- Electricity MeSH
- Electrophoresis, Capillary MeSH
- Pharmaceutical Preparations * MeSH
- Humans MeSH
- Membranes, Artificial * MeSH
- Solvents MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
The coarse-grained Martini force field is widely used in biomolecular simulations. Here we present the refined model, Martini 3 ( http://cgmartini.nl ), with an improved interaction balance, new bead types and expanded ability to include specific interactions representing, for example, hydrogen bonding and electronic polarizability. The updated model allows more accurate predictions of molecular packing and interactions in general, which is exemplified with a vast and diverse set of applications, ranging from oil/water partitioning and miscibility data to complex molecular systems, involving protein-protein and protein-lipid interactions and material science applications as ionic liquids and aedamers.
Ionic liquids are increasingly used for their superior properties. Four water-immiscible ionic liquids (butyltriethylammonium bis(trifluoromethylsulfonyl)imide, octyltriethylammonium bis(trifluoromethylsulfonyl)imide, dodecyltriethylammonium bis(trifluoromethylsulfonyl)imide, butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) and their water miscible precursors (bromides) were synthesized in a microwave reactor and by conventional heating. The best conditions for microwave-assisted synthesis concerning the yield and the purity of the product are proposed. The heating in the microwave reactor significantly shortened the reaction time. Biocide and ecotoxic effects of synthesized ionic liquids and their precursors were investigated. All tested compounds had at least a little effect on the growth or living of microorganisms (bacteria or mold). The precursor dodecyltriethylammonium bromide was found to be the strongest biocide, but posed a risk to the aquatic environment due to its relatively high EC50 value in the test with Vibrio fischeri. We assumed that apart from the alkyl chain length, the solubility in water, duration of action, or type of anion can influence the final biocide and ecotoxic effect.
- MeSH
- Aliivibrio fischeri drug effects MeSH
- Ammonium Compounds chemistry MeSH
- Anti-Bacterial Agents chemical synthesis pharmacology MeSH
- Antifungal Agents chemical synthesis chemistry pharmacology MeSH
- Ecotoxicology methods MeSH
- Imidazoles chemistry MeSH
- Ionic Liquids chemical synthesis pharmacology MeSH
- Quaternary Ammonium Compounds chemical synthesis pharmacology MeSH
- Microwaves MeSH
- Drug Evaluation, Preclinical methods MeSH
- Publication type
- Journal Article MeSH
Aqueous solutions of ionic liquids (ILs) with surface active properties were used as extraction solvents, taking advantage of their impressive solvation properties, in a green microwave-assisted solid-liquid extraction method (IL-MA-SLE) for the extraction of flavonoids from passion fruit and mango leaves. The extraction method was combined with high-performance liquid chromatography and photodiode-array detection (HPLC-PDA) and optimized by response surface methodology using the Box-Behnken experimental design. Under optimum conditions, the extraction efficiency of six structurally different IL-based surfactants was evaluated. Thus, imidazolium-, guanidinium- and pyridinium-type ILs with different tailorable characteristics, such as side chain length and multicationic core, were assessed. The decylguanidinium chloride ([C10Gu+][Cl-]) IL-based surfactant was selected as key material given its superior performance and its low cytotoxicity, for the determination of flavonoids of several samples of Passiflora sp. and Mangifera sp. leaves from the Canary Islands, and using as target analytes: rutin, quercetin and apigenin. The analysis of 50 mg of plant material only required 525 µL of the low cytotoxic IL-based surfactant solution at 930 mM, 10.5 min of microwave irradiation at 30 °C and 50 W, which involves a simpler, faster, more efficient and greener method in comparison with other strategies reported in the literature for obtaining bioactive compounds profiles from plants.
- MeSH
- Flavonoids chemistry isolation & purification MeSH
- Ionic Liquids chemistry MeSH
- Plant Leaves chemistry MeSH
- Mangifera chemistry MeSH
- Microwaves MeSH
- Passiflora chemistry MeSH
- Surface-Active Agents chemistry MeSH
- Plant Extracts chemistry MeSH
- Solvents chemistry MeSH
- Rutin chemistry MeSH
- Publication type
- Journal Article MeSH
