Liquid Nanocomposite Research Articles

Co-Delivery of Arsenotungstate Polyoxometalate and Curcumin Using Bis-Imidazolium Poly Ionic Liquid Nanocomposites for Boosting Anticancer Effects against Triple-negative Breast Cancer Cells

Co-Delivery of Arsenotungstate Polyoxometalate and Curcumin Using Bis-Imidazolium Poly Ionic Liquid Nanocomposites for Boosting Anticancer Effects against Triple-negative Breast Cancer Cells

α-Fe2O3/, Co3O4/, and CoFe2O4/MWCNTs/Ionic Liquid Nanocomposites as High-Performance Electrocatalysts for the Electrocatalytic Hydrogen Evolution Reaction in a Neutral Medium.

Transition metal oxides are a great alternative to less expensive hydrogen evolution reaction (HER) catalysts. However, the lack of conductivity of these materials requires a conductor material to support them and improve the activity toward HER. On the other hand, carbon paste electrodes result in a versatile and cheap electrode with good activity and conductivity in electrocatalytic hydrogen production, especially when the carbonaceous material is agglomerated with ionic liquids. In the present work, an electrode composed of multi-walled carbon nanotubes (MWCNTs) and cobalt ferrite oxide (CoFe2O4) was prepared. These compounds were included on an electrode agglomerated with the ionic liquid N-octylpyridinium hexafluorophosphate (IL) to obtain the modified CoFe2O4/MWCNTs/IL nanocomposite electrode. To evaluate the behavior of each metal of the bimetallic oxide, this compound was compared to the behavior of MWCNTs/IL where a single monometallic iron or cobalt oxides were included (i.e., α-Fe2O3/MWCNTs/IL and Co3O4/MWCNTs/IL). The synthesis of the oxides has been characterized by X-ray diffraction (XRD), RAMAN spectroscopy, and field emission scanning electronic microscopy (FE-SEM), corroborating the nanometric character and the structure of the compounds. The CoFe2O4/MWCNTs/IL nanocomposite system presents excellent electrocatalytic activity toward HER with an onset potential of -270 mV vs. RHE, evidencing an increase in activity compared to monometallic oxides and exhibiting onset potentials of -530 mV and -540 mV for α-Fe2O3/MWCNTs/IL and Co3O4/MWCNTs/IL, respectively. Finally, the system studied presents excellent stability during the 5 h of electrolysis, producing 132 μmol cm-2 h-1 of hydrogen gas.

Simple Magnetic Polymeric Ionic Liquid Nanocomposite Coated Hollow Fiber Membrane for the Determination of Lead (II) and Copper (II) in Water and Fruit Juice with Microinjection Sampling-Flame Atomic Absorption Spectrometry (MIS-FAAS)

A novel and effective adsorbent based on magnetic polymeric ionic liquid nanocomposite-coated hollow fiber membrane (MPILNC-HFM) was developed and applied for magnetic solid phase extraction of Pb (II) and Cu (II) from environmental water and fruit juice samples with microinjection sampling-flame atomic absorption spectrometry (MIS-FAAS). During extraction process, the adsorbent coated on the surface of the hollow fiber can be removed from the solution using tweezers without using a magnet. Additionally, the need to use a centrifuge during adsorption and desorption steps is also eliminated, thereby increasing the speed, simplicity, and efficiency of the extraction process. The nanocomposite characterized through Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy-dispersive x-ray (EDX) analyses to ensure its applicability. The experimental parameters were optimized by applying one-variable-at the-time (OVAT) approach. Under optimal conditions, limits of detection were achieved 16.5 µg L−1 for Pb (II) and 20.4 µg L−1 for Cu (II), respectively, with relative standard deviations up to 7.9% and relative recoveries in the range of 91.8%–02.2%.

Determination of bortezomib and dasatinib anticancer drugs in real samples using an electrochemical sensor modified with new CuFe2O4/SmVO4/ionic liquid nanocomposite

Determination of bortezomib and dasatinib anticancer drugs in real samples using an electrochemical sensor modified with new CuFe2O4/SmVO4/ionic liquid nanocomposite

Nanoadditives induced enhancement of thermal energy storage properties of molten salt: Insights from experiments and molecular dynamics simulations

Current concentrated solar power (CSP) plants use molten salts as heat storage and heat transfer medium. The thermal property enhancement of molten salts can increase the efficiency and lower the investment cost of CSP plants. In this study, the experiments and molecular dynamics (MD) simulations were employed to investigate the effect of doping Al2O3, SiO2 nanoparticles or multi-walled carbon nanotubes (MWCNTs) on the specific heat capacity (SHC) of ternary carbonate salt. The results show that the SHC of molten salt can be enhanced by adding nanoadditives. The addition of MWCNTs has the largest SHC enhancement in both solid and liquid states. Based on MD simulations, the radial distribution functions, number density distribution and vibrational density of states were further analyzed to reveal the effect of nanoadditive, base salt and interface thermal resistance between them on SHC at different temperatures. It is found that the nanoadditive agglomeration, the ion spacing of base salt, and the thermal resistance between base salt and nanoadditive is independent on temperature and cannot result in the enhanced SHC of liquid nanocomposites. Moreover, the thickness of interfacial layer changes with temperature. The thicker interfacial layer leads to the higher SHC of liquid nanocomposites. The interfacial layer also has a decisive influence on SHC of solid nanocomposites. The scanning electron microscopy images show that the layered, needle-like, and network-like interfacial layers are observed in Al2O3, SiO2 and MWCNT nanocomposites, respectively. The present findings are helpful to understand the mechanisms governing thermal energy storage, and provide guidelines for the performance optimization of molten salt based nanocomposites.

A novel electron transfer kinetic for terbutaline detection using Tio2-MWCNTs-IL modified GCE

Herein, we report a novel electrochemical detection method based on nanocomposite modified glassy carbon electrode (GCE) nano-sensor for terbutaline (TBS). Titanium oxide nanoparticles (TiO2NPs) were synthesized and the respective titanium oxide nanoparticles-multi walled carbon nanotubes-ionic liquid (TiO2-MWCNTs-IL) nanocomposite was successfully prepared. Subsequently, the surface morphology, functional groups and thermal stability of the synthesized TiO2NPs and the nanocomposite aspects were analysed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR) and thermal gravimetric analysis (TGA), respectively. In addition, electrochemical characterization of the fabricated TiO2-MWCNTs-IL-GCE was examined using electrochemical impedance spectroscopy (EIS) in order to ensure the material's suitability in electro-catalytic sensing by investigating the electron transfer kinetics of the redox probe at the modified electrode-solution interface. TiO2-MWCNTs-IL-GCE exhibited excellent significant electro-catalytic activity for the electro-oxidation of TBS at optimized electrochemical experimental conditions. The reproducibility, stability as well as the detection limits were determined. A wide linear range of 0.5 μM–3.0 μM as well as limit of detection (LOD) and limit of quantification (LOQ) of 0.016 μM and 0.214 μM, respectively, were obtained and the results were compared with similarly reported electrodes for terbutaline detection. In addition, the TiO2-MWCNTs-IL-GCE sensor has superb stability, selectivity and repeatability. Moreover, the fabricated electrode was also used for determination of TBS in its drug formulation with good percentage recovery performance (93.0%–100.2%).

Evaluation of least square support vector machine, generalized regression neural network and response surface methodology in modeling the removal of Levofloxacin and Ciprofloxacin from aqueous solutions using ionic liquid @Graphene oxide@ ionic liquid NC

This study focused on the preparation, characterization of a supported dicationic ionic liquid nanocomposite (IL@GO@IL NC) and employing of it in the adsorption of Levofloxacin (LVX) and Ciprofloxacin (CPF) antibiotic. Also, the nonlinear least square support vector machine (N-LSSVM), generalized regression neural network (GRNN), along with response surface methodology used for modeling the removal of both antibiotics (i.e. LVX and CPF) from aqueous solution. In this work, the experiments designed based on critical parameters such as adsorbent dose, antibiotic concentration, sonication time and temperature. The nonlinear adsorption isotherms and kinetics models as well as thermodynamic used for fitting the experimental data. The statistical results demonstrated that the LSSVM and GRNN model efficiently predicted the antibiotics removal percentage with very high accuracy, respectively. Furthermore, for an optimal adsorption of LVX and CPF by IL@GO@IL NC, the adsorbent dose, antibiotic concentration, temperature and sonication time should be set to 0.23 and 0.35 g, 95.20 and 100.00 mg L-1, 2.10 and 4.60 min, and 45.00 ℃, for LVX and CPF, respectively. Under these optimal conditions, the removal percentages and adsorption capacity of LVX and CPF will be 98.20 and 97.50%, as well as 730 and 630 mg g−1, respectively. Besides, the IL@GO@IL NC efficiency under optimal conditions drops up by 15% after seven cycles for both antibiotics. Therefore, the IL@GO@IL NC may be considered as a promising option in removing fluoroquinolones antibiotics from water.

Carbon Nanofiber-Ionic Liquid Nanocomposite Modified Aptasensors Developed for Electrochemical Investigation of Interaction of Aptamer/Aptamer-Antisense Pair with Activated Protein C.

Selective and sensitive detection of human activated protein C (APC) was performed herein by using carbon nanofiber (CNF) and ionic liquid (IL) composite modified pencil graphite electrode (PGE) and electrochemical impedance spectroscopy (EIS) technique. A carbon nanomaterial-based electrochemical aptasensor was designed and implemented for the first time in this study for the solution-phase interaction of DNA-Apt with its cognate protein APC as well as APC inhibitor aptamer-antidote pair. The applicability of this assay developed for the determination of APC in fetal bovine serum (FBS) and its selectivity against different proteins (protein C, thrombin, bovine serum albumin) was also examined. CNF-IL modified aptasensor specific to APC provided the detection limit as 0.23 μg/mL (equal to 3.83 nM) in buffer medium and 0.11 μg/mL (equal to 1.83 nM) in FBS. The duration of the proposed assay from the point of electrode modification to the detection of APC was completed within only 55 min.

Improved Lead Sensing Using a Solid-Contact Ion-Selective Electrode with Polymeric Membrane Modified with Carbon Nanofibers and Ionic Liquid Nanocomposite.

A new solid-contact ion-selective electrode (ISE) sensitive to lead (II) ions, obtained by modifying a polymer membrane with a nanocomposite of carbon nanofibers and an ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate, is presented. Electrodes with a different amount of nanocomposite in the membrane (0-9% w/w), in which a platinum wire or a glassy carbon electrode was used as an internal electrode, were tested. Potentiometric and electrochemical impedance spectroscopy measurements were carried out to determine the effect of the ion-sensitive membrane modification on the analytical and electrical parameters of the ion-selective electrode. It was found that the addition of the nanocomposite causes beneficial changes in the properties of the membrane, i.e., a decrease in resistance and an increase in capacitance and hydrophobicity. As a result, the electrodes with the modified membrane were characterized by a lower limit of detection, a wider measuring range and better selectivity compared to the unmodified electrode. Moreover, a significant improvement in the stability and reversibility of the electrode potential was observed, and additionally, they were resistant to changes in the redox potential of the sample. The best parameters were shown by the electrode obtained with the use of a platinum wire as the inner electrode with a membrane containing 6% of the nanocomposite. The electrode exhibited a Nernstian response to lead ions over a wide concentration range, 1.0 × 10-8-1.0 × 10-2 mol L-1, with a slope of 31.5 mV/decade and detection limit of 6.0 × 10-9 mol L-1. In addition, the proposed sensor showed very good long term stability and worked properly 4 months after its preparation without essential changes in the E0 or slope values. It was used to analyze a real sample and correct results of lead content determination were obtained.

Ionic Liquid-Functionalized ZrO2/Reduced Graphene Oxide Nanocomposites for Carcinoembryonic Antigen Electrochemical Detection

Herein, we develop an electrochemical immunosensor based on a zirconia-reduced graphene oxide-1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM.BF4) ionic liquid (ZrO2-rGO-IL) nanocomposite for the detection of a carcinoembryonic antigen (CEA) breast cancer biomarker. The characterization results of the synthesized ZrO2-rGO-IL nanocomposite show that it has high electroconductivity, oxygen functionalities, and a larger active surface area, which favors high loading of anti-CEA antibodies. The fabricated BSA/anti-CEA/ZrO2-rGO-IL/GCE immunosensor can detect CEA with high sensitivity and selectivity in a broad detection range between 25.0 fg mL–1 and 25.0 ng mL–1 with an ultralow limit of detection (LOD) of 1.23 fg mL–1 through differential pulse voltammetry (DPV). In addition, we tested the CEA in serum samples having linear detection ranges from 100.0 fg mL–1 to 5.0 ng mL–1 with an LOD of 2.25 fg mL–1. Subsequently, the incubation time and selectivity of the immunosensor show a great affinity for CEA. Therefore, the proposed immunosensor can be a promising candidate for CEA detection in clinical specimens. Prospectively, the synthesized nanocomposite will have the potential for the effective detection of other cancer biomarkers.

Diagnostic kit based on halloysite nanoclay-ionic liquid nanocomposite modified electrode for electrochemical determination of cancer biomarker

Nucleic acid hybridization is occurred between the selective single-stranded nucleic acid sequence and its target sequence, which is one of the essential procedure for electrochemical detection of nucleic acid. microRNA-21 (miRNA-21) is known as a biomarker in various cancers. The determination of miRNA-21 was attained through by hybridization of inosine substituted miRNA-21 specific DNA probe (Pinosine) with its target miRNA-21. In this study, the surface of pencil graphite electrode (PGE) was firstly modified with halloysite nanoclay-ionic liquid (HNT/IL) nanocomposite. The characterization of surface was performed by Scanning Electron Microscope (SEM) images and Energy Dispersive X-Ray Analysis (EDX) analysis, and the differences at surface modifications were also shown by electrochemical methods with electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). For sensitive and selective determination of miRNA-21, Pinosine and target miRNA concentration, immobilization and hybridization time were optimized by using HNT/IL modified PGE in combination with differential pulse voltammetry (DPV). The detection limit was achieved as 0.17 μg/mL (equals to 23.69 nM) in the linear range of 0.25–2 μg/mL miRNA-21. The selectivity of voltammetric method based on HNT/IL-PGE developed for miRNA-21 was examined in the presence of mismatch (MM) and non-complementary (NC) sequences. Because miRNA-21 is over-expressed in cancer cells, it has been tested in total RNA samples isolated from cancer cell line (breast cancer cell line, MCF-7). In the total RNA samples obtained from MCF-7, the detection limit was calculated as 0.28 μg/mL in the linear range of 1–4 μg/mL. Besides, the healthy cell line (human embryonic kidney cell line, HEK-293) was used as a control group and the results obtained by MCF-7 total RNA samples were compared to the results using HEK-293 total RNA samples in terms of miRNA-21 level.

A Novel Electrochemical Sensor for the Determination of Diphenylhydramine Hydrochloride Based on a Carbon Paste Electrode (CPE) Modified with Ferrite–Cobalt–Silica/Ionic Liquid Nanocomposite

A Novel Electrochemical Sensor for the Determination of Diphenylhydramine Hydrochloride Based on a Carbon Paste Electrode (CPE) Modified with Ferrite–Cobalt–Silica/Ionic Liquid Nanocomposite

Drop-coated molybdenum disulfide-ionic liquid for improving the electrochemical chiral recognition ability of chitosan

A faithful and facile strategy to significantly improve the electrochemical chiral recognition ability of chitosan is proposed via drop-coating molybdenum disulfide-ionic liquid (MoS 2 -IL) nanocomposite. • MoS 2 -IL was first used to improve the enantiorecognition ability of CS. • There is a good linear relationship between the DPV peak potential and ee. • The proposed sensor exhibited satisfactory reproducibility and stability. • The proposed sensor exhibited enantiorecognition ability for other enantiomers. A faithful strategy to significantly improve the enantiorecognition ability of chitosan (CS) is proposed via drop-coating molybdenum disulfide (MoS 2 )-ionic liquid (IL) nanocomposite. The present work describes a novel, simple, and effective chiral interface based on MoS 2 -IL/CS nanocomposite which was elaborately integrated to combine the electrical signal amplification and space complexity of MoS 2 -IL and vast enantiorecognition sites of CS for the electrochemical enantiorecognition of tryptophan (Trp) enantiomers. Differential pulse voltammetry (DPV) was adopted to evaluate the potential differences (ΔE P ) between the oxidation peaks of l -Trp and d -Trp. MoS 2 -IL/CS nanocomposite showed higher chiral recognition ability result from spatial asymmetry of MoS 2 -IL/CS. Herein, several parameters, such as drop-coated volume and concentration of MoS 2 -IL, electrodeposited viscosity, time and temperature of CS, detection temperature and pH were optimized in order to obtain a large ΔE P signal between l -Trp and d -Trp, and the ΔE P value can reach 53.3 mV under optimal conditions. Furthermore, different percentages of Trp mixtures and DPV peaks potential were detected with a good linear relationship even in the real sample, which indicated that MoS 2 -IL/CS chiral interface could effectively quantify the enantiomer excess (ee) of Trp enantiomers in Trp mixtures.

Green electrochemical sensors based on ionic liquid nanocomposites for detection of environmental pollutants

Industrialization and globalization have caused a huge burden on the limited natural resources, which releases various environmental pollutants such as toxic metal ions and pesticides. World Health Organisation (WHO) has set a maximum permissible limit for these toxic pollutants in water, above which, it is unsuitable for drinking purpose. There are various techniques available for the determination of such pollutants like ICP-MS, HPLC, FAAS etc. that are costly, cumbersome, and time consuming. Whereas, electrochemical sensors are portable, fast and can perform multi-analyte sensing. Electrochemical sensor can be made selective by fabricating with nanocomposites having different functional groups. Nowadays, trend of utilizing greener materials in research field is being highly appreciated in accordance with the principles of green chemistry for the application and development of electrochemical sensors. Ionic liquids having non-volatility, low toxicity, wide potential window, high electrochemical stability and conductivity have shown sustainable electrochemical sensing applications. Nanocomposite of these ionic liquids as a sensing platform have been extensively used in electrochemical detection of various pollutants. This work provides a literature survey of different ionic liquid nanocomposite based sensing platform for electrochemical detection of toxic pesticides and heavy metals. They have demonstrated good sensitivity with detection limit below WHO guidelines.

Immobilization Polyoxometalate/Ionic Liquid Nanocomposites on Hexagonally Ordered Silica as Solid Coating in Microextraction of Polycyclic Aromatic Hydrocarbons

The eventuality of determination of polycyclic aromatic hydrocarbons in water samples is studied by utilizing keggin polyoxometalate nanocluster/ionic liquid on hexagonally ordered silica as solid-phase microextraction adsorbent. Parameters affecting the extraction of polycyclic aromatic hydrocarbons into the coating such as sampling time, sampling volume, and temperature are also evaluated. In the optimized conditions, (Desorption temperature: 270 °C, Desorption duration: 2 min, Extraction temperature: 80 °C, Extraction duration: 30 min, pH: 7 and Stirring rate: 700 r.p.m) the correlation coefficients were high (≥0.9976), linear ranges were broad 0.00001-10 mgL−1) and limit of detections were suitable (≤0.36 µg L−1).

Comparative study of nitrate all solid state ion-selective electrode based on multiwalled carbon nanotubes-ionic liquid nanocomposite

Carbon nanotubes have enjoyed unflagging popularity in recent years. They are successfully used in many fields of science, including potentiometry for the construction of ion selective electrodes with solid contact. A new type of SC-ISEs sensitive to nitrate(V) ions using multiwalled carbon nanotubes-ionic liquid nanocomposite was prepared. The effect of the kind of carbon nanotubes on the parameters of SC-ISEs was investigated. The study compares, among others, detection limits, sensitivity and linearity ranges of characteristic curves, and stability of the potential measured for the tested electrodes. Electrochemical impedance spectroscopy and chronopotentiometric techniques were also used as research methods. It was found that the type of carbon nanotubes included in the nanocomposite influences both the metrological and electrical parameters of the obtained solid contact nitrate ion-selective electrode.

Sensitive electrochemical strategy via the construction of functionalized carbon nanotubes/ionic liquid nanocomposite for the determination of anaesthetic drug cinchocaine

Cinchocaine (CIN) is a local anesthetic agent that has a role in the pain reduction and itching of hemorrhoids. So, the capability to precisely determine CIN is of high need. In this study, an accurate determination of CIN was done using functionalized multiwall carbon nanotubes (f.CNT) and ionic liquid (IL) modified electrochemical carbon paste electrode (CPE) for the first time. The modified electrochemical sensor CPE/IL-f.CNT provided good stability and reproducibility towards CIN determination. The morphology and performance of CPE/IL-f.CNT were characterized using different techniques. A wide linear voltammetric response was obtained for CIN in the concentration range 1.0 × 10−7 to 4.4 × 10−5 M CIN with a detection limit of 2.0 × 10−8 M. The simultaneous determination of CIN was further studied in the presence of coadministered drugs for the first time using the electrochemical method. Furthermore, the suggested electrochemical protocol was successfully used for the CIN quantification real samples.

An electrochemical method for determination of amaranth in drinks using functionalized graphene oxide/chitosan/ionic liquid nanocomposite supported nanoporous gold

An electrochemical sensor was fabricated by modifying nanoporous gold (NPG)-coated glassy carbon electrode (NPG/GCE) with functionalized graphene oxide /chitosan/ionic liquid nanocomposites (fGO/CS/IL). The introduction of ionic liquid (IL) and chitosan (CS) induced higher dispersibility of functionalized graphene oxide (fGO), and was beneficial for the combination of fGO/CS/IL with NPG/GCE. As a result of the synergistic effect of NPG and fGO/CS/IL, the resulted functionalized graphene oxide/chitosan/ionic liquid nanocomposites/nanoporous gold /glassy carbon electrode (fGO/CS/IL/NPG/GCE) showed the highest redox peak current response signal of Amaranth (E123) due to ultrahigh surface area, electronic conductivity as well as the improvement of the surface structure. Under optimized conditions, the enhanced peak currents represented excellent analytical performance for detection of Amaranth in the concentration range from 8.0 to 1200.0 nM. Meanwhile, the fGO/CS/IL/NPG/GCE presented satisfactory sensitivity and selectivity, excellent reproducibility, and long-time stability. For practical applications, the fGO/CS/IL/NPG/GCE was validated for the determination of Amaranth in three types of drinks with satisfactory results.

PIM-based mixed-matrix membranes containing MOF-801/ionic liquid nanocomposites for enhanced CO2 separation performance

In this work, we fabricated PIM-based mixed matrix membranes (MMMs) containing MOF-801/ionic liquid nanocomposites to enhance CO2 separation performance of pure polymer membranes. All membranes and MOF-801/ionic liquid nanocomposites were prepared by solution casting method and wet impregnation, respectively. The samples were analyzed by SEM, XRD, FTIR, TGA and Nitrogen adsorption-desorption measurements. The nanocomposites are composed of metal-organic framework (MOF) MOF-801 and ionic liquid (IL) adsorption capacity. MOF-801 can well control the dispersion of IL in the polymer matrix, which is conducive to exposing more active sites in the nanocomposites to improve the CO2 adsorption selectivity of MOF-801/ionic liquid nanocomposites. At the same time, the porous structure of nanocomposites also enhances the gas adsorption and diffusion, thereby improving the gas separation performance. Compared with pure PIM-1 membranes, the CO2 permeability and CO2/N2 selectivity of IL@MOF/PIM-5% MMMs was increased by 129% and 45% (CO2 = 9420 Barrer, CO2/N2 = 29）, respectively. Compared with MOF-801/PIM-1 MMMs, the permeability of CO2 decreased slightly but the selectivity of CO2/N2 increased from 27 to 29. The aging test showed that the CO2 permeability of MMMs could remain above 70% after 90 days. The anti-plasticization performance of MMMs has also been significantly improved. The CO2 separation performance of IL@MOF/PIM-5% MMMs significantly exceeded the 2008 Robeson upper bound, showing excellent gas separation performance and working stability.

Preparation and Electrochemical Performance of Fe3O4-SWCNTs/ionic Liquid Nanocomposites as Sensor for Determination of Tert-Butylhydroquinone

Preparation and Electrochemical Performance of Fe3O4-SWCNTs/ionic Liquid Nanocomposites as Sensor for Determination of Tert-Butylhydroquinone