Creating new water-soluble Iso- and n-fatty acid arginate hydrochloride with antimicrobial properties

Typically, short- and long-chain lipids from oils exhibit different antimicrobial activities and therefore have been used in agriculture and aquaculture, biomedical therapeutic and antibacterial fields. However, these fatty acids have limitations in terms of bioactive efficacy, thermostability and aqueous solubility. In this study, water-soluble iso-fatty acid arginate hydrochloride derivatives with antimicrobial properties were produced by introducing branched (iso-) chain and other linear- (n-) chain fatty acids to the “arginine” amino acid molecule. The two-step synthetic route was straightforward and provided an efficient 88% and 76% product yields for ethyl n-oleoyl arginate hydrochloride and ethyl iso-oleoyl arginate hydrochloride, respectively. ATR-FT-IR, NMR, and LC-MS-Q-TOF techniques were used to thoroughly characterize and confirm the products. These arginate products had strong antimicrobial activities against Listeria innucua, a Gram-positive bacterium with minimum inhibitory concentrations and minimum bactericidal concentrations ranging from 1.8 µg mL⁻¹ to 29.1 µg mL⁻¹. Therefore, the study demonstrated the development of a novel class of antimicrobial compounds from iso-fatty acids and arginates.     

Antioxidant Activity of Rambutan (Nephelium lappaceum L.) Peel Extract in Soybean Oil during Storage and Deep Frying

Rambutan (Nephelium lappaceum L.) peel (RBP) is discarded as the main by‐product during processing of the fruit. Increasing attention is now paid to the valorization of RBP for the recovery of valuable compounds. Geraniin, ellagic acid, quercetin, and rutin are the main phenolic compounds found in methanolic RBP extract. Extracted rambutan peel powder (ERPP) is used to evaluate the oxidative stability of soybean oil stored at 4 and 30 °C in the dark and light and deep fried with potatoes at 160 °C. Tert‐butylhydroquinone (100 µg g^?1 oil, TBHQ) serves as positive control. Oil supplemented with ERPP of 1000 µg gallic acid equivalents (GAE) g^?1 of oil shows positive effects on the retardation of the oxidation process during storage in comparison with oil without addition. During deep frying, either ERPP (1000 µg GAE g^?1) or TBHQ retards the lipid oxidation of oil. Levels of thiobarbituric acid reactive substances of potatoes fried in oil fortified with the extract and TBHQ (0.4–0.59 µg g^?1) are much lower than those without the extract (1.31 ± 0.10 µg g^?1) (p < 0.05). Therefore, RBP extract exhibits favorable antioxidant effects and can be used for effectively inhibiting lipid oxidation in oil during storage and deep frying. Practical Applications: An extract from rambutan fruit peel containing phenolic compounds, that is, geraniin, ellagic acid, rutin, and quercetin showed promising results to be used as potential antioxidants in soybean oil during deep frying. Both oxidation of the frying oil as well as the oxidation of the food product, that is, potatoes were inhibited. These results demonstrated that rambutan fruit peel extract can be used as a natural antioxidant in frying oil to replace synthetic antioxidants, that is, TBHQ.     

Fluorescence Enhancement Effect for the Determination of Nucleic Acids With Morin–NanoTiO<Subscript>2</Subscript>

It is found that nucleic acids can greatly enhance the fluorescence intensity of morin–nanoTiO₂. Under optimum conditions, the enhanced fluorescence intensity of the system is in proportion to the concentration of nucleic acids in the range of 2.0 × 10⁻⁸ to 2.2 × 10⁻⁷ g mL⁻¹ for calf thymus DNA (ctDNA) and 1.0 × 10⁻⁸ to 2.5 × 10⁻⁷ g mL⁻¹ for yeast RNA (yRNA). The detection limits are 4.8 × 10⁻⁹ g mL⁻¹ for ctDNA and 1.2 × 10⁻⁹ g mL⁻¹ for yRNA, respectively. This method has satisfactorily been used for the determination of nucleic acids in actual sample.     

Enhancement of Polyunsaturated Fatty Acid Production by Selenium Treatment in Polyunsaturated Fatty Acid-Producing Fungus

The effect of selenium (Se) treatment on the content of intracellular polyunsaturated fatty acids (PUFA) was investigated. Selenium treatment could effectively increase the yields of arachidonic acid (AA) and linoleic acid (LA). When AA-producing Diasporangium jonesianum recombinant strain D-A1 was cultured in a medium containing 90 μg mL⁻¹ Se, the growth of D. jonesianum recombinant strain D-A1 was constrained, but the content of AA in the total fatty acids reached 9.3%, 1.7-fold higher than the control. The content of LA was also increased from 25.9 to 37.7%. Under various culture conditions, Se treatment (90 μg mL⁻¹) was generally beneficial to the yields of LA and AA. However, there was no significant increase in the contents of eicosapentaenoic acid (EPA) and γ-linolenic acid. Therefore, the use of Se is advantageous for regulating the content of intracellular PUFA in D. jonesianum recombinant strain D-A1, and could be good enhancer in the yields of AA and LA.     

Influence of different reactor types on Nannochloropsis oculata microalgae culture for lipids and fatty acid production

Greenhouse gases emitted into the atmosphere by burning of fossil fuels cause global warming. One option is obtaining biodiesel. Nannochloropsis oculata was cultured under different light intensities and reactors at 25°C for 21 days with f/2 medium to assess their effects on cell density, lipid, and fatty acids (FAs). N. oculata improved cell density on fed-batch glass tubular reactor (7 L) at 200 μmol E m⁻² s⁻¹, yielding 3.5 × 10⁸ cells ml⁻¹, followed by fed-batch Erlenmeyer flask (1 L) at 650 μmol E m⁻² s⁻¹ with 1.7 × 10⁸ cells ml⁻¹. The highest total lipid contents (% g lipid × g dry biomass⁻¹) were 44.4 ± 0.8% for the reactor (1 L) at 650 μmol E m⁻² s⁻¹ and 35.2 ± 0.2% for the tubular reactor (7 L) at 200 μmol E m⁻² s⁻¹, until twice as high compared with the control culture (Erlenmeyer flask 1 L, 80 μmol E m⁻² s⁻¹) with 21.2 ± 1%. Comparing the total lipid content at 200 μmol E m⁻² s⁻¹, tubular reactor (7 L) and reactor 1 L achieved 35.2 ± 0.2% and 28.3 ± 1%, respectively, indicating the effect of shape reactor. The FAs were affected by high light intensity, decreasing SFAs to 2.5%, and increased monounsaturated fatty acids + polyunsaturated fatty acids to 2.5%. PUFAs (20:5n-3) and (20:4n-3) were affected by reactor shape, decreasing by half in the tubular reactor. In the best culture, fed-batch tubular reactor (7 L) at 200 μmol E m⁻² s⁻¹ contains major FAs (16:0; 38.06 ± 0.16%), (16:1n-7; 30.74 ± 0.58%), and (18:1n-9; 17.15 ± 0.91%).     

Superhydrophobic-superoleophilic heptafluorodecyl triethoxysilane/graphitic carbon spheres Co-modified porous monolith for water/oil separation

Water/oil separation has been a flourishing research focus due to severe oil-spill accidents. The current work reports on preparation, characterization and water/oil separation performance of heptafluorodecyl triethoxysilane (FAS) and graphitic carbon spheres (GCS) co-modified mullite porous ceramic (FAS/GCS-MC) with superhydrophobic and superoleophilic characters. The water contact angle of FAS/GCS-MC was determined as about 161°. The continuous water/oil separation rates for paraffin, vegetable and vacuum pump oils were 3.4 × 10⁴ g m⁻² min⁻¹, 2.2 × 10⁴ g m⁻² min⁻¹ and 1.3 × 10⁴ g m⁻² min⁻¹, respectively; even after 10 cycles, the separation rates remained almost unchanged in high selectivity (above 95%). The as-prepared FAS/GCS-MC was resistant to the temperature change and acid/base erosion, and showed stable superhydrophobicity and separation efficiency. In addition, the separation rate after applied a voltage to FAS/GCS-MC could be obviously enhanced by a self-heating process.     

Electrochemical Sensor for Detection of Trichlorfon Based on Molecularly Imprinted Sol–Gel Films Modified Glassy Carbon Electrode

Thin films of molecularly imprinted sol–gel polymer with specific binding sites for trichlorfon were prepared, fixed on glassy carbon electrodes and used as recognition material. The binding characteristic of the imprinted films to trichlorfon was evaluated by equilibrium binding experiments; and, the morphology was studied by scanning electronic microscope. A novel electrochemical sensor for determination of trichlorfon was developed based on the reaction between trichlorfon and the molecularly imprinted sol–gel film, which was a modified glassy carbon electrode. The sensor displayed excellent selectivity and high sensitivity. The linear response range of the sensor was 10⁻⁸ –10⁻⁶ g mL⁻¹, and the limit of detection was 2.8 × 10⁻⁹ g mL⁻¹. The relative standard deviation for the determination of 10⁻⁷ g mL⁻¹ trichlorfon was 3.5%. The sensor was applied to the determination of trichlorfon in vegetables with satisfactory results.     

Synthesis and Anti-Listeria Properties of Odorless Hybrid Bio-Based n-Phenolic Vegetable Branched-Chain Fatty Acids

Consumers are becoming concerned about the impact of synthetic chemicals on human health and environments, and demanding natural compounds to reduce risk of antibiotic resistance of microorganisms. However, natural compounds are often less effective than synthetic antimicrobials. This challenge may be addressed with the development of bio-based antimicrobial agents. In this study, bio-based n-phenolic branched-chain fatty acids (n-phenolic-branched chain fatty acid [BCFA]) were synthesized from vegetable oil (soybean and safflower) fatty acids and four natural phenolics (phenol, thymol, carvacrol, and creosote), and tested against Listeria innocua. Results revealed that the newly synthesized products in crude form had minimum inhibitory concentrations (MIC) against L. innocua ranging from 3.6 to 116.4 μg mL⁻¹, with phenol-BCFA products having the lowest MIC (3.6 μg mL⁻¹) and minimum bactericidal concentration (MBC) (7.3 μg mL⁻¹). The precursors (unsaturated free fatty acids and phenolics) and noncovalently bound mixture of free fatty acids and phenolics had MIC above 232.7 μg mL⁻¹. After purification by molecular fractionation, n-phenolic-BCFA in the free fatty acid/monomer form were shown to be responsible for the anti-Listeria activity with MIC of 3.6–7.3 μg mL⁻¹ and MBC of 7.3–29.1 μg mL⁻¹. These promising results pave the road for further study of this new class of bio-based compounds, which may lead to their widespread use.     

Electrochemical sensing platform based on tris(2,2′-bipyridyl)cobalt(III) and multiwall carbon nanotubes–Nafion composite for immunoassay of carcinoma antigen-125

A new strategy for constructing a sensitive mediator-type electrochemical immunosensor for the detection of carcinoma antigen-125 (CA125) was developed. In this strategy, mediator tris(2,2′-bipyridyl)cobalt(III) (Co(bpy)₃³⁺) was incoporated into the multiwall carbon nanotubes–Nafion (MWNTs–Nafion) composite film via a simple ion-exchange route. Then, gold colloidal nanoparticles (nano-Au) were attached onto Co(bpy)₃³⁺/MWNTs–Nafion film through electrostatic interaction between negatively charged nano-Au and positively charged Co(bpy)₃³⁺. Finally, CA125 monoclonal antibody (anti-CA125), used as a model antibody, was assembled onto the surface of nano-Au to achieve an immunosensor for the determination of CA125 antigen. X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to characterize the assembly process of the modified electrode. The resulting immunosensor showed a high sensitivity, wide dynamic range consisting of two linear parts from 1.0 to 30 U mL⁻¹ and 30 to 150 U mL⁻¹ with a low detection limit of 0.36 U mL⁻¹ at 3 times the background noise. Moreover, it displayed good reproducibility and stability, and would be potentially attractive for clinical immunoassay of CA125. The integration of mediator Co(bpy)₃³⁺ and MWNTs–Nafion composite would offer potential promise for the fabrication of biosensors and biocatalysts.     

Novel bismuth/multi-walled carbon nanotubes-based electrochemical sensor for the determination of neuroprotective drug cilostazol

A very sensitive electrochemical sensor has been developed by modification of glassy carbon electrode (GCE) with nanoparticles of bismuth (III) oxide (Bi₂O₃) and multi-walled carbon nanotubes (MWCNTs). The sensor was applied for the determination of cilostazol, cyclic nucleotide phosphodiesterase inhibitors in pharmaceutical formulation and human plasma. The voltammetric responses were compared with those obtained at bare GCE under optimum conditions. The cyclic and square-wave voltammograms of cilostazol showed 3.3 and 4.9 times enhancement in the oxidation peak current at MWCNTs–Bi₂O₃/GCE as compared to a bare GCE. Bi₂O₃–MWCNTs/GCE showed a linear response for cilostazol in standard solution over the concentration range of 0.8–13 μg mL⁻¹ with the detection limit 0.76 μg mL⁻¹, whereas human plasma over the concentration range 0.8–12.5 μg mL⁻¹ with the detection limit 0.66 μg mL⁻¹.     

Effect of processing parameters on microstructure and ablation behavior of SiC/ZrB2 coating for graphite

In this research, a SiC/ZrB₂ coating was produced on graphite by reactive melt infiltration and plasma spraying method. The coating characterization was performed using XRD analysis, electron microscopy equipped with energy dispersive spectrometer (EDS), and supersonic flame ablation test at 2073 K. The results indicated that the dense C/SiC coating with good ablation resistance can be obtained at 1873 K. The coating thickness decreased with increasing infiltration temperature. The results of ablation test showed that by increasing the infiltration temperature and holding time, weight loss and mass ablation rate decreased from 22.63% to 9.83% and 3.63 × 10⁻³ g cm⁻² s⁻¹ to 1.34 × 10⁻³ g cm⁻² s⁻¹, respectively. The results showed that by using the ZrB₂ as outer coating the ablation resistance improved remarkably. The weight loss and mass ablation rates for the SiC/ZrB₂ coating were 12.79% and 1.857 × 10⁻³ g cm⁻² s⁻¹, respectively.     

Comprehensive Identification of Principal Lipid Classes and Tocochromanols in Silkworm (Antheraea pernyi and Bombyx mori) Pupae Oils

A comprehensive identification of lipid compositions and tocochromanols in Antheraea pernyi (A. pernyi) and Bombyx mori (B. mori) pupae oil is reported in the present study. Fatty acid profiling shows that both oils contain high levels (79.67% vs 71.11%) of unsaturated fatty acids, especially linoleic acid and linolenic acid. Moreover, linolenic acid is preferentially enriched at the sn‐2 positions of triacylglycerols (TAGs). Liquid chromatograph‐mass spectrometry (LC‐MS) analysis demonstrates that POO (TAG with one palmitoyl and two oleoyls) is the primary TAG form with percentages of 20.18% in A. pernyi and 15.00% in B. mori. The dominating phospholipid species are phosphatidylcholine (PC, 30.40% vs 54.61%) and phosphatidylethanolamine (PE, 34.82% vs 20.39%). Four sterol constituents with total contents of 382.56 ± 3.12 and 371.65 ± 2.98 µg g^?1 are identified and analyzed quantitatively. Additionally, the levels of tocochromanols (20.15 ± 0.89 vs 17.15 ± 0.71 mg g^?1) are quantified in both silkworm pupae oils. Overall, silkworm oil acts as an enriched source of functional lipids and tocochromanols. Practical Applications: A systematic investigation on the principal lipid classes and tocochromanols of Antheraea pernyi pupae and Bombyx mori pupae oil is reported in this study. The informative data provide supporting evidence for comprehensive utilization of silkworm oil for production of nutritional and healthy products.     

Functional Gelatin-Carbon Nanotubes Nanohybrids With Enhanced Antibacterial Activity

Hybrid materials with enhanced antibacterial activity were prepared by incorporation of carbon nanotubes within gelatin-fluoroquinolones bioconjugates. Gelatin bioconjugates were characterized by UV-Vis, FT-IR, and calorimetric analyses, nanohybrids by morphological analyses. Biocompatibility was evaluated on human mesenchymal stem cells, and antibacterial performance against Klebsiella pneumoniae and Escherichia coli. Minimun inhibitory concentrations from 0.025 to 0.05 µg mL^?1 and from 0.025 to 0.10 µg mL^?1, and MBC from 0.025 to 0.10 µg mL^?1 and from 0.05 to 0.20 µg mL^?1 were detected for Escherichia coli and Klebsiella pneumoniae, respectively, showing that nanotubes increase antimicrobial activity comparing to both free and gelatin-conjugated drugs.     

Ultrathin and nanofibers via room temperature electrospinning from trifluoroacetic acid solutions of untreated lignocellulosic sisal fiber or sisal pulp

Lignocellulosic sisal fiber (LSF) and sisal pulp (SP) were electrospun at room temperature from solutions in trifluoroacetic acid (TFA) prepared at concentrations of 2 × 10⁻² g mL⁻¹ and 3 × 10⁻² g mL⁻¹, respectively. Scanning electron microscopy images of the electrospun LSF showed fibers with diameters ranging from 120 to 510 nm. The presence of defects decreased along with increasing the flow rate of the SP solution, which generated nanofibers and ultrathin fibers with diameters in the range of 40–60 (at 5.5 µL min⁻¹) up to 90–200 nm (at 65.5 µL min⁻¹). Despite the known ability of TFA to esterify the hydroxyl groups present in the starting materials, the Fourier transform infrared spectra indicated the absence of trifluoroacetyl groups in the electrospun samples. The thermal stability of the final materials proved suitable for many applications even though some differences were observed relative to the starting materials. This study demonstrated a feasible novel approach for producing nano/ultrathin fibers from lignocellulosic biomass or its main component, which allows for a wide range of applications for these materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41826.     

Preparation of Gd2Zr2O7 nanoceramics from two-step thermal treatment and the aqueous durability analysis

Gd₂Zr₂O₇ ceramics demonstrate important prospect in the immobilization of high-level radioactive wastes (HLWs). In this study, Gd₂Zr₂O₇ nanoceramics were fabricated using two-step method, where Gd₂Zr₂O₇ nanopowder was firstly synthesized by solvothermal method and Gd₂Zr₂O₇ nanoceramics were subsequently sintered via self-propagating chemical furnace plus quick pressing (SCF/QP). The characterization results display that the Gd₂Zr₂O₇ nanocrystalline ceramics with average grain size of 78 nm and bulk density of 5.53 g cm⁻³ were successfully prepared. The results of MCC-1 static leaching experiments show that the normalized release rate (LR_i) of Gd is 2.2 × 10⁻² g m⁻²•d⁻¹ on the first day and converges to 1.2 × 10⁻³ g m⁻²•d⁻¹ after 42 days. Zr shows superior chemical stability as the 21 days LR_Zr value is as low as 2.7 × 10⁻⁶ g m⁻²•d⁻¹, which becomes constant as the leaching duration prolongs.     

Effect of phenol on Β-carotene content in total carotenoids production in cultivation of<Emphasis Type="Italic">Rhodotorula glutinis</Emphasis>

The composition of carotenoids produced byR. glutinis was observed to be dependent upon the addition of phenol into medium. A stimulatory effect of phenol on Β-carotene ofRhodotorula glutins K-501 grown on glucose was investigated. Carotenoids produced byRhodotorula glutinis K-501 were identified to torularhodin, torulene and Β-carotene, whose composition was 79.5%, 6.4% and 14.1%, respectively. The Β-carotene content increased up to 35% when phenol was added to culture media at 500 ppm. The ratio of torularhodin decreased with increasing phenol concentration, while torulene content was almost constant.     

Ultrasonic propagation in high-concentration TiO2 slurries for photocatalytic reactors

This work reports measurements of the speed of sound and ultrasonic attenuation in high concentration (up to 3 g · L⁻¹) aqueous TiO₂ slurries close to neutral pH. Measurements were made at frequencies of 1675, 5545, and 9340 kHz using ultrasonic transducers submerged in the slurry. The experimental setup may be applied to slurries in practical reactors while in operation. Within an experimental uncertainty of ±0.5 m · s⁻¹, the speed of sound in the slurry was the same as in pure water, at all the studied catalyst concentrations and frequencies. The excess ultrasonic attenuation with respect to pure water increases linearly with the catalyst concentration and is inversely proportional to the square of the excitation frequency. This indicates that viscous and thermal acoustic losses predominate over scattering. For TiO₂ concentrations in the range of 0.15–3 g · L⁻¹, the catalyst concentration in the slurry may be estimated as a linear function of the excess ultrasonic attenuation, with an uncertainty of 0.1 g · L⁻¹.     

Effect of a Seaweed Extract on Fatty Acid Accumulation and Glycerol-3-Phosphate Dehydrogenase Activity in 3T3-L1 Adipocytes

This study was to determine the effect of a seaweed Ascophyllum nodosum extract (SE) containing 220 mg g⁻¹ phlorotannins on differentiation and fatty acid accumulation in differentiating 3T3-L1 adipocytes. 3T3-L1 cells (2 × 10⁴ mL⁻¹) were seeded to 24-well plates and proliferated to reach confluence and then were treated with media containing 0, 12.5, 25, 50, 75 and 100 μg mL⁻¹ SE for 8 days. Dexamethasone, methyl-isobutylxanthine and insulin (DMI) were added to the media in the first 2 days to induce cell differentiation. On day 8 the adipocytes were harvested for measuring cellular fatty acid concentration and the activity of glycerol-3-phosphate dehydrogenase (GPDH). It was found that treatment with SE increased (P < 0.01, n = 6) cellular myristoleic acid (C14:1), palmitoleic acid (C16:1) and oleic acid (C18:1) and total monounsaturated fatty acids (MUFA) without significantly affecting the cell number and saturated fatty acid (SFA). Ratios of MUFA/SFA, C14:1/C14:0, C16:1/C16:0 and C18:1/C18:0 in cellular lipids increased (P < 0.05, n = 6) with the SE treatment in a dose dependent manner (P < 0.001). Treatment with 75 μg mL⁻¹ SE depressed (P < 0.05) cellular GPDH activity. The results indicate that the biological factors in the SE may be involved in differentiation and MUFA accumulation in adipocytes.     

Surfactant-Mediated Catalytic Determination of Fe(II) in Herbal and Pharmaceutical Products

In the present work, the catalyzed oxidation of neutral red (NR) by bromate was used to work out a kinetic-based analytical method as an alternative technique for the determination of Fe(II) in real and synthetic samples. A use of a surfactant, N-dodecylpyridinium chloride enhanced the sensitivity of the reaction by becoming involved in the reaction mechanism and providing a more suitable reaction environment. The iron-catalyzed oxidation of NR with potassium bromate was studied kinetically by using a fixed time method. The reaction was followed by measuring the decrease in absorbance at 535 nm. The use of a surfactant in the analytical run showed a five times increase in the sensitivity of the method. It served as a ready reservoir of NR by increasing its solubilization. The salt effect, pH, and reagent concentration were also investigated to achieve a more selective and sensitive analytical procedure. Under optimized conditions (4.2 × 10⁻⁵ mol L⁻¹ NR, 1.4 × 10⁻³ mol L⁻¹ KBrO₃, 1.5 × 10⁻² mol L⁻¹ cationic surfactant, 0.5 mol L⁻¹ LiCl and pH 2.60 at 30 °C), iron(II) was determined in the range 0.1–0.5 μg mL⁻¹ with a detection limit of 0.019 μg mL⁻¹ and a relative standard deviation (n = 6) 1.02% for 0.2 μg mL⁻¹ Fe(II). The influence of foreign ions on the accuracy of the results was investigated. The developed method is extremely sensitive, selective and simple. The method was applied successfully to the determination of iron in the herbal pharmaceutical and synthetic samples. The results showed good agreement with those obtained by atomic absorption spectrophotometry.

One-pot green hydrothermal synthesis of bio-derived nitrogen-doped carbon sheets embedded with zirconia nanoparticles for electrochemical sensing of methyl parathion

We report a simple, economical and green one-pot hydrothermal strategy to synthesize the bio-derived nitrogen-doped carbon sheets (ONCSs) embedded with zirconia nanoparticles (ZrO₂NPs) with orange juice as carbon source and solvent. The ONCSs-ZrO₂NPs composite was further applied in the decoration of glassy carbon electrode (GCE) for electrochemical sensing of methyl parathion. The orange juice-derived ONCSs with graphene-like micromorphology showed good electrical conductivity, large specific surface area, and nitrogen functional groups. They could accelerate the electron transport, provide sufficient electrolyte-electrode interface, and improve the surface wettability, thus forming a suitable microenvironment for the redox reaction of MP. The embedded ZrO₂NPs in graphene-like ONCSs possessed a strong affinity toward the phosphorus groups on MP molecules, which could promote the preconcentration of MP in the interface of the fabricated sensor and electrolyte. Benefitting from the synergistic effect of ONCSs and ZrO₂NPs/GCE, the ONCSs-ZrO₂NPs/GCE sensor exhibited excellent peak current response towards MP with a linear detection range of 0.01–15 μg mL⁻¹ and a low detection limit of 0.115 ng mL⁻¹. Furthermore, the ONCSs-ZrO₂NPs/GCE sensor presented good capability to investigate the MP levels in romaine and kiwifruit juices with satisfactory recoveries. This work provides a novel and green one-step approach in the development of carbon-based composite materials for high-performance MP electrochemical sensors.