Non-enzymatic electrochemical impedance sensor for selective detection of electro-inactive organophosphate pesticides using Zr-MOF/ZrO2/MWCNT ternary composite.

The existence of multiple pesticide residues in fruits and vegetables constitutes a direct peril to living organisms. Therefore, it is crucial to develop a low-cost screening method for determining organophosphate pesticides (OPPs) in food samples. This study describes the solvothermal synthesis of a ternary composite comprising multi-walled carbon nanotubes (MWCNT), zirconium oxide, and a zirconium-metal-organic framework (Zr-MOF). The ternary composite was characterised using XRD, FESEM, FTIR, and BET. The ternary composite provides a large surface area (1158 m2/g) compared with the pristine Zr-MOF (868 m2/g). The composite-modified glassy carbon electrode was used to determine nine pesticides, including organophosphate (malathion, dimethoate, chlorpyrifos, monocrotophos, and glyphosate) and non-organophosphate (thiophanate methyl, carbendazim, atrazine, and 2,4, D). In particular, various chemical combinations of OPPs were selected, such as S-P=S, P=S, P=O, and non-OPPs such as C=S (with sulphur), and without sulphur. The sensor results show that the sensor selectivity is high for OPPs containing both phosphorus and sulphur molecules. The low detection limit of the sensor was 2.02, 2.8, 2.5, 1.11, and 2.01 nM for malathion, chlorpyrifos, dimethoate, monocrotophos, and glyphosate, respectively. The electrode exhibited significant chemical stability (93%) after 100 cycles, good repeatability, and a long shelf life. The sensor is reliable for qualitative real-time applications.

Engineered photonic near-infrared light activated photothermal theranostic nanovaccine induced targeted remodeling of tumor microenvironment.

Tumor recurrence, which happens as a result of persisting tumor cells and minor lesions after treatments like surgery and chemotherapy, is a major problem in oncology. Herein, a strategy to combat this issue by utilize a theranostic nanovaccine composed of photonic HCuS. This nanovaccine aims to eradicate cancer cells and their traces while also preventing tumor recurrence via optimizing the photothermal immune impact. Successful membrane targeting allows for the introduction of new therapeutic agents into the tumor cells. Together with co-encapsulated Toll-Like Receptors (TLR7/8) agonist R848 for activating T cells and maturing DCs, the combined effects of HCuS and ICG function as photothermal agents that generate heat in the presence of NIR light. Photothermal-mediated immunotherapy with therapeutic modalities proved successful in killing tumor cells. By activating the immune system, this new photonic nanovaccine greatly increases immunogenic cell death (ICD), kills tumor cells, and prevents their recurrence.

Highly Selective Room Temperature Detection of NH3 and NOx Using Oxygen-Deficient W18O49-Supported WS2 Heterojunctions.

In this paper, we reported the controlled synthesis of tungsten disulfide/reduced tungsten oxide (WS2/W18O49) heterojunctions for highly efficient room temperature NOx and ammonia (NH3) sensors. X-ray diffraction analysis revealed the formation of the oxygen-deficient W18O49 phase along with WS2. Field-emission scanning electron microscopy and transmission electron microscopy displayed the formation of WS2 flakes over W18O49 nanorods. X-ray photoelectron spectroscopy showed the presence of tungsten in W4+, W5+, and W6+ oxidation states corresponding to WS2 and W18O49, respectively. The WS2/W18O49 heterojunction sensor exhibited sub-ppm level sensitivity to NOx and NH3 at room temperature. The heterojunction sensor detected 0.6 ppm NOx and 0.5 ppm NH3, with a corresponding response of 7.1 and 3.8%, respectively. The limit of detection of the sensor was calculated to be 0.05 and 0.17 ppm for NH3 and NOx, respectively. The cyclic stability test showed that the sensor exhibited high stability even after 24 cycles for the detection of NH3 and 14 cycles for NOx. Compared to pristine WO3 and WS2, the WS2/W18O49 heterojunction showed high selectivity toward NOx and NH3. The results could be useful for the development of room temperature NOx and NH3 sensors.

A cationic amino acid polymer nanocarrier synthesized in supercritical CO2 for co-delivery of drug and gene to cervical cancer cells.

The present study was undertaken to investigate the ability of a drug curcumin-loaded polymer to inhibit the growth of cervical cancer cells by enhancing the anti-cancer efficiency of curcumin. We synthesized poly(methacryloyl beta-alanine) (PMBA) as a nanocarrier by radical polymerization in supercritical CO2. The results showed that the curcumin encapsulated and folic acid (FA)-treated PMBA (Poly@Cur-FA) for 24 h activated the reactive oxygen species-mediated programmed cell death machinery in HeLa cells. This remarkable effect of Poly@Cur-FA treatment was visualized using different fluorescent probes, which demonstrated that the Poly@Cur-FA treatment disrupted the cell membrane, as also supported by scanning electron microscopy observations. The effect of Poly@Cur-FA dispersion on the cells was observed under a transmission electron microscope. Further, the HeLa cells were treated with the polymer encapsulated curcumin and Bcl2 siRNA (Pol-Cur-siRNA) for 24 h, which effectively suppressed the Bcl2 and simulated the autophagic pathway. This co-delivery system was designed to inhibit curcumin efflux and can enhance the treatment efficacy by targeting multiple signaling pathways, including cell cycle, apoptotic, and autophagic pathways. Collectively, the Pol-Cur-siRNA system appears to offer an efficient combinational therapeutic strategy that might overcome the problems associated with the chemosensitivity against the standard synthetic anti-cancer drugs. To support the experimental data, an artificial neural network model was developed to foresee the drug and gene release behaviors.

Metal-organic frameworks with different oxidation states of metal nodes and aminoterephthalic acid ligand for degradation of Rhodamine B under solar light.

Metal-organic frameworks (MOFs) have been investigated recently as effective visible light photocatalysts. In this report, we synthesized nickel, iron, and titanium-based MOFs with different oxidation states of metal ions and aminoterephthalic acid ligand for photocatalytic degradation of Rhodamine B (RhB) dye under solar light irradiation. The photoluminescence analysis revealed that the Fe-MOF could suppress the recombination of photoinduced charges and effectively degrade the dye. The photocatalytic experiment demonstrated that the Fe-MOF exhibited higher degradation efficiency of dye (90 %) compared to the Ni-MOF (9 %) and Ti-MOF (50 %) at pH 7 in 90 min. In addition, the effects of catalyst amount, dye concentration, and solution pH on dye degradation were investigated. The photodegradation of dye using Fe-MOF was well-fitted to the first-order kinetics with an R2 value of 0.9987. Furthermore, reactive oxygen species test and electron paramagnetic resonance study revealed that the superoxide anion radicals were mainly responsible for the dye degradation. Cyclic test analysis indicates that there was no substantial decrease in the degradation efficiency of dye after four consecutive cycles.

Graphitic carbon nitride/NH2-MIL-101(Fe) composite for environmental remediation: Visible-light-assisted photocatalytic degradation of acetaminophen and reduction of hexavalent chromium.

Herein, an efficient photocatalyst composed of graphitic carbon nitrate and iron-based metal-organic framework (g-C3N4/NH2-MIL-101(Fe)) composite was fabricated by a solvothermal method for the degradation of acetaminophen (AAP) and reduction of Cr(VI) under sunlight illumination. The composite was confirmed by X-ray diffraction. UV-visible spectra showed that the bare g-C3N4, pure Fe-MOF, and composite harvest solar light effectively. The photocatalytic experiment indicated that the composite exhibited superior reduction efficiency of Cr(VI) (66%) compared to the bare g-C3N4 (35%) and pure Fe-MOF (51%) at pH 7. As the pH decreases from 9 to 2, the reduction efficiency increased. The highest Cr(VI) reduction (91%) was observed at pH 2. On the other hand, the catalyst degraded 94% of AAP at pH 7 compared to the bare g-C3N4 (42%) and pure Fe-MOF (60%) in the presence of hydrogen peroxide. A radical scavenger experiment endorsed that the generation of superoxide radicals was the main reason for the AAP degradation. The cyclic stability test indicated that there was no substantial decrease in the degradation efficiency of AAP after ten repeated cycles. The kinetic studies showed that the photodegradation of AAP and reduction Cr(VI) was well-fitted to the first-order kinetics. Gas chromatography-mass spectrometry analysis showed that hydroquinone, aliphatic carboxylic acids, monohydroxy, and dihydroxy paracetamol were the main products formed as a result of such degradation process. Therefore, the iron-based MOF and their composites can be used as effective photocatalysts for pollutants degradation.

Partners in crime: The Lewis Y antigen and fucosyltransferase IV in Helicobacter pylori-induced gastric cancer.

Helicobacter pylori (H. pylori) is a major causative agent of chronic gastritis, gastric ulcer and gastric carcinoma. H. pylori cytotoxin associated antigen A (CagA) plays a crucial role in the development of gastric cancer. Gastric cancer is associated with glycosylation alterations in glycoproteins and glycolipids on the cell surface. H. pylori cytotoxin associated antigen A (CagA) plays a significant role in the progression of gastric cancer through post-translation modification of fucosylation to develop gastric cancer. The involvement of a variety of sugar antigens in the progression and development of gastric cancer has been investigated, including type II blood group antigens. Lewis Y (LeY) is overexpressed on the tumor cell surface either as a glycoprotein or glycolipid. LeY is a difucosylated oligosaccharide, which is catalyzed by fucosyltransferases such as FUT4 (α1,3). FUT4/LeY overexpression may serve as potential correlative biomarkers for the prognosis of gastric cancer. We discuss the various aspects of H. pylori in relation to fucosyltransferases (FUT1-FUT9) and its fucosylated Lewis antigens (LeY, LeX, LeA, and LeB) and gastric cancer. In this review, we summarize the carcinogenic effect of H. pylori CagA in association with LeY and its synthesis enzyme FUT4 in the development of gastric cancer as well as discuss its importance in the prognosis and its inhibition by combination therapy of anti-LeY antibody and celecoxib through MAPK signaling pathway preventing gastric carcinogenesis.

Visible light-assisted degradation of 4-nitrophenol and methylene blue using low energy carbon ion-implanted ZnO nanorod arrays: Effect on mechanistic insights and stability.

The present investigation demonstrates an enhancement of the visible photocatalytic activities by C ion implantation in ZnO nanorod arrays (NRAs). Vertically aligned ZnO NRAs were prepared by seed layer assisted solution-phase growth and implanted with 70 keV carbon ions at various fluencies: 1E15, 5E15, 1E16, and 3E16 ions/cm2. X-ray diffraction and FESEM results revealed the crystalline 1D ZnO NRAs having a length of ∼3 µm with a diameter in the range of 150-200 nm. C implantation induces the absorption towards the visible region and a substantial decrease in the optical bandgap energy from 3.2 eV to 2.43 eV. The photocatalytic activities (PC) of C ion-implanted ZnO NRAs were investigated through the degradation of 4-Nitrophenol (4-NP) and methylene blue dye (MB) under ambient visible light irradiation. The degradation efficiency of C ion-implanted ZnO NRAs increases compared to the pristine ZnO NRAs from 60.12% to 93.7% and 48.6 to 97.5% for MB and 4-NP, respectively. The synergistic effects of low energy carbon ion-induced bulk and surface interface electronic states facilitate a narrow band of visible light absorption and efficient charge separation to increase the visible-light-driven photocatalytic performance of ZnO NRAs.

Hexagonal nanostructured cobalt oxide @ nitrogen doped multiwalled carbon nanotubes/polypyyrole composite for supercapacitor and electrochemical glucose sensor.

Hexagonal nanostructured cobalt oxide @ N-doped MWCNT /polypyyrole (Co3O4/PPy@N-MWCNT) composite was produced by an ultrasonication-mediated solvothermal method for electrochemical supercapacitor and glucose sensor applications. The structural and electrochemical properties of the Co3O4/PPy@N-MWCNT were confirmed by various spectroscopic and microscopic techniques. The as-prepared electrode showed an excellent capacitance of ∼872 F/g at 0.5 A/g with a capacitance retention of 96.8 %, even after 10,000 cycles. In addition, analysis of the sensing activity of the composite materials towards the glucose detection showed excellent electrochemical sensing performance that includes the glucose linear limit of (10 to 0.15) µm, detection sensitivity of 195.72 µA/cm2/mM, and lower detection value of S = 0.07327 µA/cm2 @ R2 = 0.99. The as-prepared composite material can be a promising candidate for the electrochemical supercapacitor and the efficient sensing of glucose.

Synergistic Effect of Photothermally Targeted NIR-Responsive Nanomedicine-Induced Immunogenic Cell Death for Effective Triple Negative Breast Cancer Therapy.

Triple negative breast cancer (TNBC) is a breast cancer subtype. At present, TNBC patients do not have approved targeted therapy. Therefore, patients primarily depend on forceful systemic chemotherapy that has unavoidable harmful side effects, resulting in inadequate therapeutic outcomes and leading to a high mortality rate. Hence, there is an urgent need to develop targeted therapies for the TNBC populace. Developing a new nanotherapeutic approach of combinational therapy could be an effective alternative strategy. Therefore, we designed a combination of hyaluronan (HA)-polyaniline (PANi)-imiquimod (R837), denoted as HA-PANi/R837, nanoparticles (NPs) that exhibited a high extinction coefficient of 8.23 × 108 M-1 cm-1 and adequate photothermal conversion efficiency (PCE) (η = 41.6%), making them an efficient photothermal agent (PTA) that is highly beneficial for selective CD44-mediated photothermal ablation of TNBC tumors. Furthermore, co-encapsulation of R837 (toll-like receptor 7 agonist) immunoadjuvant molecules triggers an immune response against the tumor. The formed CD44-targeted HA-PANi/R837 NPs' selectivity incinerates the tumor under near-infrared (NIR)-triggered photothermal ablation, generating tumor-associated antigens and triggering R837 combination with anti-CTLA-4 for immunogenic cell death (ICD) activation to kill the remaining tumor cells in mice and protect against tumor relapse and metastasis. Our results demonstrated that novel HA-PANi/R837 NP-induced photothermal ICD achieved in CD44-targeted TNBC is a promising application.

Bioreceptor-free, sensitive and rapid electrochemical detection of patulin fungal toxin, using a reduced graphene oxide@SnO2 nanocomposite.

In this research, we successfully synthesized a reduced graphene oxide/tin oxide (rGO/SnO2) composite for the electrochemical detection of fungal contaminant, patulin (PAT) that does not require a biological or chemical receptor or specific antibodies. The resulting rGO/SnO2 composite exhibited promising electrochemical properties and demonstrated outstanding performance in the direct measurement of PAT levels in contaminated apple juice samples. The differential pulse voltammetric response of the rGO/SnO2 composite electrode exhibited a linear relationship with PAT concentration in the 50-600 nM range and had a lower detection limit of 0.6635 nM. The sensor electrode exhibited high sensitivity, reliable reproducibility, and good selectivity. The designed electrochemical sensor was also tested against the time-consuming and conventional high-performance liquid chromatography (HPLC) approach for the detection of PAT in spiked apple juice samples. We found that the electrochemical sensor had ability to rapidly detect PAT in apple juice samples without the need of extraction or clean-up steps and achieved a higher recovery rate (74.33 ± 0.70 to 99.26 ± 0.70%) within a short-time analysis than did by the HPLC (61.97 ± 1.78 to 84.31 ± 1.96%), thus illustrating its feasibility for use in agricultural and food safety industries.

Fluorescent immunoliposomal nanovesicles for rapid multi-well immuno-biosensing of histamine in fish samples.

Scombroid poisoning in fish-based and other food products has raised concerns due to toxicity outbreaks and incidences associated with histamine, thus measuring the amount of histamine toxic molecule is considered crucial quality indicator of food safety and human health. In this study, liposome-based measurement of histamine was performed via rupturing mechanism of sulforhodamine B dye encapsulated anti-histamine antibody conjugated liposomal nanovesicles. The immunosensing ability of immuno-liposomal format was assessed by monitoring the fluorescence at excitation/emission wavelength of 550/585 nm. Immuno-liposomal format assays were considered, one based on single wash procedure (Method 1), which had a detection limit of 10 ppb and quantification limit 15-80 ppb. While Method 2 based on one-by-one wash procedure had a detection limit of 2-3 ppb and quantification limit 8.5 ppb-200 ppm that required 2 h 30 min to perform. In view of better quantification limit, Method 2 was chosen for further tests required to validate its applicability in real samples. The feasibility of Method 2 was reconfirmed in fresh mackerel fish, and canned fish (tuna and salmon) with a similar detection limits but with low amplified fluorescence signals and sufficient levels of histamine recovery from fresh mackerel (73.50-99.98%), canned tuna (79.08-103.74%) and salmon (74.56-99.02%). The specificity and method accuracy were expressed as % CV in the range 5.34%-8.48%. Overall, the developed multi-well sensing system (Method 2) showed satisfactory specificity, cost effectiveness, rapidity, and stability for monitoring histamine toxicity as a practical food diagnostic device.

A Sustainable Graphene Aerogel Capable of the Adsorptive Elimination of Biogenic Amines and Bacteria from Soy Sauce and Highly Efficient Cell Proliferation.

A graphene aerogel (GA) with a three-dimensional (3D) structure, ultra-lightweight nature, and high hydrophobicity was simply fabricated by the one-step pyrolysis of glucose and ammonium chloride. The as-synthesized GA exhibited a 3D interconnected microporous architecture with a high surface area of ∼2860 m2 g-1 and pore volume of 2.24 cm3 g-1. The hydrophobic GA (10 mg 100 mL-1) demonstrated rapid and excellent adsorption performance for the removal of food toxins such as various biogenic amines (histamine, cadaverine, and spermine) and the hazardous bacterium Staphylococcus aureus (a food contaminant and a cause of poor wound healing) from a liquid matrix with a maximum simultaneous adsorption capacity for multiple biogenic amines of >85.19% (histamine), 74.1% (cadaverine), and 70.11% (spermidine) and a 100% reduction in the viable cell count of S. aureus within 80 min of interaction. The outstanding adsorption capacity can be attributed to a highly interconnected porous network in the 3D architecture and a high surface-to-volume ratio. A case study using soy sauce spiked with multiple biogenic amines showed successful removal of toxins with excellent recyclability without any loss in absorption performance. Biocompatibility of the GA in terms of cell viability was observed even at high concentrations (83.46% and 75.28% at 25 and 50 mg mL-1, respectively). Confirmatory biocompatibility testing was conducted via live/dead cell evaluation, and the morphology of normal lung epithelial cells was examined via scanning electron microscopy showed no cellular shrinkage. Moreover, GA showed excellent removal of live colonies of S. aureus from the food matrix and immunoblotting analysis showed elevated protein expression levels of ß-catenin and α-SMA (α-smooth muscle actin). The biocompatible sugar-based GA could simultaneously adsorb multiple biogenic amines and live bacteria and was easy to regenerate via simple separation due to its high floatability, hydrophobicity, surface area, and porosity without any structural and functional loss, making it especially relevant for food safety and biomedical applications.

Nitrogen-Implanted ZnO Nanorod Arrays for Visible Light Photocatalytic Degradation of a Pharmaceutical Drug Acetaminophen.

The present study focuses on the effects of nitrogen (N) ion implantation in vertically aligned ZnO nanorod arrays (NRAs) and the photocatalytic degradation of acetaminophen. The X-ray diffraction of these NRAs exhibit a wurtzite structure with a predominant (002) diffraction peak that shifts slightly after N-ion implantation. The field emission scanning electron microscopic images of as-prepared NRAs show a length of ∼4 µm and diameter of ∼150 nm. UV-visible spectroscopy reveals that the band gap of pristine ZnO NRAs decreases from 3.2 to 2.18 eV after N-ion implantation. Under visible irradiation, the N-ion-implanted ZnO catalyst exhibits significant enhancement of the photocatalytic degradation of acetaminophen from 60.0 to 98.46% for 120 min.

A protamine-conjugated gold decorated graphene oxide composite as an electrochemical platform for heparin detection.

In this study, an effective electrochemical sensor was developed for heparin detection using a protamine-conjugated graphene oxide/gold (GO/Au) composite. Protamine is an antidote that can act as an affinity ligand for heparin. The GO was used as support for signal amplification, and Au nanoparticles (NPs) were employed to immobilize the protamine. This Au NPs also increasing the electron transfer rate and enhancing the signal response during protamine-heparin integration. The proposed affinity sensor had a simple fabrication process, a low detection limit (0.9 nM), a wide linear range (1.9 × 10-7 M to 1.5 × 10-9 M), high stability, and high selectivity in the detection of heparin.

Versatile Poly(Diallyl Dimethyl Ammonium Chloride)-Layered Nanocomposites for Removal of Cesium in Water Purification.

In this work, we elucidate polymer-layered hollow Prussian blue-coated magnetic nanocomposites as an adsorbent to remove radioactive cesium from environmentally contaminated water. To do this, Fe3O4 nanoparticles prepared using a coprecipitation method were thickly covered with a layer of cationic polymer to attach hollow Prussian blue through a self-assembly process. The as-synthesized adsorbent was confirmed through various analytical techniques. The adsorbent showed a high surface area (166.16 m²/g) with an excellent cesium adsorbent capacity and removal efficiency of 32.8 mg/g and 99.69%, respectively. Moreover, the superparamagnetism allows effective recovery of the adsorbent using an external magnetic field after the adsorption process. Therefore, the magnetic adsorbent with a high adsorption efficiency and convenient recovery is expected to be effectively used for rapid remediation of radioactive contamination.

Electrochemical coupled immunosensing platform based on graphene oxide/gold nanocomposite for sensitive detection of Cronobacter sakazakii in powdered infant formula.

A sensitive electrochemical immunosensing platform for the detection of Cronobacter sakazakii was developed using a graphene oxide/gold (GO/Au) composite. Transmission electron microscopy showed that the Au nanoparticles, with an average size of < 30 nm, were well dispersed on the GO surface. For the detection of C. sakazakii, a polyclonal anti-C. sakazakii antibody (IgG) was covalently immobilized to the Au nanoparticles on the surface of the GO/Au composite coated glassy carbon electrode (GCE). The electrochemical sensing performance of immunofunctionalized GCE was characterized by cyclic voltammetry and differential pulse voltammetry. Under optimized conditions, in pure culture there was a linear relationship between electrical signal and C. sakazakii levels over the range 2.0 × 102-2.0 × 107 cfu/mL (R2 = 0.999), with a detection limit of 2.0 × 101 cfu/mL. The total analytical time was 15 min per sample. The C. sakazakii electrochemical immunosensing assay was able to successfully detect 2.0 × 101 cfu/mL of C. sakazakii in artificially contaminated powdered infant formula without any enrichment or pre-enrichment steps. Furthermore, the recovery rates of the C. sakazakii electrochemical immunosensing assay following spiking of powdered infant formula with different concentrations of C. sakazakii (cfu/mL) were 82.58% at 2.0 × 101 cfu/mL, 84.86% at 2.0 × 102 cfu/mL, and 95.40% at 2.0 × 103 cfu/mL. The C. sakazakii electrochemical immunosensing assay had good selectivity, reproducibility, and reactivity compared with other Cronobacter spp. and/or pathogens belonging to other genera, indicating its significant potential in the clinical diagnosis of C. sakazakii.

Porous 3D Prussian blue/cellulose aerogel as a decorporation agent for removal of ingested cesium from the gastrointestinal tract.

In the present study, we successfully synthesized a porous three-dimensional Prussian blue-cellulose aerogel (PB-CA) composite and used it as a decorporation agent for the selective removal of ingested cesium ions (Cs+) from the gastrointestinal (GI) tract. The safety of the PB-CA composite was evaluated through an in vitro cytotoxicity study using macrophage-like THP-1 cells and Caco-2 intestinal epithelial cells. The results revealed that the PB-CA composite was not cytotoxic. An adsorption study to examine the efficiency of the decorporation agent was conducted using a simulated intestinal fluid (SIF). The adsorption isotherm was fitted to the Langmuir model with a maximum Cs+ adsorption capacity of 13.70 mg/g in SIF that followed pseudo-second-order kinetics. The PB-CA composite showed excellent stability in SIF with a maximum Cs+ removal efficiency of 99.43%. The promising safety toxicology profile, remarkable Cs+ adsorption efficacy, and excellent stability of the composite demonstrated its great potential for use as an orally administered drug for the decorporation of Cs+ from the GI tract.

A composite consisting of microporous carbon and cobalt(III) oxide and prepared from zeolitic imidazolate framework-67 for voltammetric determination of ascorbic acid.

A nanoporous carbon/cobalt oxide (NPC/Co3O4) composite was synthesized from a single-precursor (zeolitic imidazolate framework-67). Transmission electron microscopy showed that the Co3O4 nanoparticles with an average particle size of 10 nm (±2 nm) were well dispersed in the NPC matrix. However, in a few places, Co3O4 nanoparticles were aggregated. The composite shows outstanding performance in terms of electrooxidation of ascorbic acid (AA) in phosphate buffer of pH 7.0. The differential pulse voltammetric response of the composite electrode (at 0.12 V vs. SCE) is linear in the 2-240 µM AA concentration range, with a 20 nM detection limit. The electrode exhibits high sensitivity (0.13 µA·µM·cm-2), reliable reproducibility, and good selectivity. The method, when applied to the direct determination of AA in vitamin C tablets, gave recoveries between 98.0 and 102.0%. Graphical abstract A nanoporous carbon composite decorated with Co2O3 nanoparticles was prepared from a single precursor (the zeolitic imidazolate framework-67). It shows outstanding performance in terms of electrooxidation of ascorbic acid with high sensitivity (0.13 µA·µM·cm-2), reliable reproducibility, and good selectivity.

Current Demands for Food-Approved Liposome Nanoparticles in Food and Safety Sector.

Safety of food is a noteworthy issue for consumers and the food industry. A number of complex challenges associated with food engineering and food industries, including quality food production and safety of the food through effective and feasible means can be explained by nanotechnology. However, nanoparticles have unique physicochemical properties compared to normal macroparticles of the same composition and thus could interact with living system in surprising ways to induce toxicity. Further, few toxicological/safety assessments have been performed on nanoparticles, thereby necessitating further research on oral exposure risk prior to their application to food. Liposome nanoparticles are viewed as attractive novel materials by the food and medical industries. For example, nanoencapsulation of bioactive food compounds is an emerging application of nanotechnology. In several food industrial practices, liposome nanoparticles have been utilized to improve flavoring and nutritional properties of food, and they have been examined for their capacity to encapsulate natural metabolites that may help to protect the food from spoilage and degradation. This review focuses on ongoing advancements in the application of liposomes for food and pharma sector.