Carbon Dioxide Bubbles Research Articles

Chemiluminescence resonance energy transfer-based immunostimulatory nanoparticles for sonoimmunotherapy

Sonodynamic therapy (SDT) has recently emerged as a promising alternative to photodynamic therapy because of its applicability in treating deeply located tumors accessible by ultrasound (US). However, the therapeutic potential of conventional sonosensitizers is limited by the low quantum yield of reactive oxygen species (ROS) and poor immune responses eliciting canonical apoptosis of cancer cells. Herein, we report chemiluminescence resonance energy transfer (CRET)-based immunostimulatory nanoparticles (iCRET NPs) for sonoimmunotherapy, which not only amplify the ROS quantum yield of sonosensitizers but also generate carbon dioxide (CO2) bubbles to induce immunogenic cell death in the tumor microenvironment (TME). Owing to their CRET phenomena responsive to H2O2 in the TME, iCRET NPs exhibit strong cytotoxicity to cancer cells by producing a large quantity of ROS. Additionally, iCRET NPs effectively induce CO2-mediated immunogenic cell death by rupturing the cancer cell membrane in the presence of US, leading to the release of bare damage-associated molecular patterns, such as HSP 70 and HMGB1. Consequently, when iCRET NPs are combined with anti-PD-1 antibodies, iCRET NPs exhibit synergistic effects in 4T1 tumor-bearing mice, in which antitumor immunity is remarkably amplified to inhibit tumor growth and metastasis.

Development of effervescence-assisted switchable polarity solvent homogeneous liquid-phase microextraction for the determination of permethrin and deltamethrin in water samples prior to gas chromatography-flame ionization detection.

An effervescent tablet-assisted switchable polarity solvent-based homogeneous liquid-phase microextraction combined with gas chromatography with flame ionization detection has been conducted for the separation, preconcentration, and detection of permethrin and deltamethrin in the river water specimens. Triethylamine (TEA) was utilized as the switchable polarity solvent in this method. The switching process was carried out by the dissolution of an effervescent tablet including an effervescency agent (sodium carbonate) and a proton donor agent (citric acid). Changing the pH of the specimen solution enhanced the conversion of TEA into protonated triethylamine carbonate through the tablet that generated carbon dioxide bubbles in situ. Finally, the addition of sodium hydroxide changed the ionization state of TEA and separated the two phases. Influential factors in the extraction were investigated. According to optimal situations, the limit of detection and the limit of quantification were 0.16 and 0.5 μg L-1 for permethrin and 0.03 and 0.1 μg L-1 for deltamethrin, respectively. The preconcentration factor was 194 in river water samples and inter- and intra-day precision (relative standard deviation %; n = 5) was <5%. The extraction recovery was obtained in the range of 93.0%-97% for permethrin and deltamethrin in water samples.

Enhancing the performance of direct methanol fuel cells via a new anode design for carbon dioxide bubbles removal

Direct methanol fuel cells (DMFCs) are primary candidates to power portable electronics. However, carbon dioxide bubbles that are generated on the anode side block the flow of reactants and negatively affect the cell’s performance. Therefore, a new secondary hydrophobic degassing channel is attached to the top of the main anode channel. The proposed design introduces an upward capillary force on CO2 bubbles toward a degassing channel that collects the actuated bubbles and leads to reactant flow without bubbles in the main channel. In the current study, parallel and serpentine flow fields are investigated to assess the effect of the new design on bubble removal and overall cell performance. Thus, an experimental study is performed on a transparent DMFC using both optical observations and electrochemical characterization methods. Results show that the new design significantly enhances the cell’s performance at high current densities. In addition, the new design is advantageous in terms of removing bubbles away from the diffusion layer, especially for the parallel flow field configuration. A comparison between the output power of the new designs and the original ones indicated that the parallel flow field with the new design outperformed both the plain serpentine and the plain parallel flow field with over 14% and 23%, respectively. The advantage of using a parallel flow field is minimizing the pumping pressures required at the anode inlet, which decreases the parasitic power consumption. Based on the current findings, anode blocking can be prevented using the new design, which improves the performance of DMFCs in the mass transport region, and allows for a higher output power per cell.

Highly Efficient Preconcentration of Per- and Polyfluoroalkyl Substances (PFAS) by Anodically Generated Shrinking Gas Bubbles

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants that have been used in many applications, including firefighting foams, stain repellents, nonstick coatings, and electroplating. Due to the extremely strong carbon-fluorine bonds in PFAS, they are highly stable and environmentally persistent. Because of their stability, PFAS can lead to bioaccumulation in humans and cause various health issues, including prostate and kidney cancer, thyroid disease, and cardiovascular disease. PFAS widely contaminate the river and lake water systems and hence cause contaminations in the drinking water. Analytical methods used for PFAS detection are currently dominated by chromatography in combination with mass spectrometry. U.S. EPA has established health advisory levels at 70 parts per trillion (70 ng/L) for PFOA and PFOS individually or combined in drinking water. Since this is a very low PFOA/PFOS concentration, preconcentrating the sample up to a detectable level plays a vital role and is an essential step during the analysis. Herein we present a novel preconcentration method for PFAS using electrogenerated shrinking gas bubbles, which can preconcentrate the PFOA and PFOS by 1300 folds within 15 minutes.Our preconcentration method is based on the natural phenomenon called sea-spray aerosol enrichment. Once air gets trapped inside a liquid column, and as these air bubbles start moving to the top through the liquid column, surface-active compounds can be preferentially adsorbed onto the air/liquid interface of the bubble. When these bubbles reach the air/liquid interface at the top of the liquid column, they burst and produce aerosol droplets enriched with surface-active compounds. Rather than using an external gas supply to generate bubbles, we in situ electrogenerated O2 and CO2 bubbles by water oxidation in the presence of 0.2 M ammonium bicarbonate as an electrolyte. The advantages of using anodically enriched bubbles bursting aerosol are 2-fold. The first one is in an ammonium bicarbonate electrolyte; the anodic side generates oxygen bubbles and carbon dioxide bubbles. Since carbon dioxide bubbles get shrunk, the effective surface area reduces. Hence the surface concentration of PFAS increases. With that high surface concentration of PFAS, the droplet's effective concentration becomes higher when it becomes aerosol droplets. The second one is when the electrolysis happens, the anode is charged positively. Due to the charge interactions, PFAS can pre-regulate near the electrode surface and provide additional preconcentration. We tested eight PFAS compounds, including perfluoroalkyl sulfonates and carboxylates. All the perfluoroalkyl carboxylate compounds show an average of 50% increase in the enrichment for the anodically enriched bubble aerosol than the cathodically enriched bubble aerosol. Furthermore, all the perfluoroalkyl sulfonate compounds show an average of 30% enrichment in the anodically enriched bubble aerosol than the cathodically enriched bubble aerosol. Due to its high contribution to environmental contamination, we used perfluorooctanoic acid (PFOA) as our model analyte. Enrichment ratios for different concentrations of PFOA ranging from 10-11 M to 10-7 M show an average of 1050 fold enrichment. To test our bubble shrinking theory, we measured the radius of the bubbles at different heights from the electrode surface. We observed an 87.5% volume reduction when the bubble moves a distance of 17.5 cm from the electrode surface to the air-water interface. We measured the enrichment ratio vs different heights to test the surface interaction between the PFAS molecules and the electrode surface. We obtained the intercept of 400 from the anodic compartment, while from the cathodic enrichment, we obtained the intercept of 200. The intercept (enrichment at zero height) involves two factors. The first one is a higher PFAS content at the air-water interface, which may cause enrichment at zero height. However, this factor is common for both compartments. However, the anodic side electrode is positively charged, and since PFAS are negatively charged, there can be a surface interaction and causing additional enrichment in the anodic side. Furthermore, our method is compatible with the LC/MS/MS method because ammonium bicarbonate is LC/MS/MS friendly solvent. Moreover, we successfully couple this technique with our previously published bubble nucleation-based electrochemical detection. This novel technique may lead to a path toward building a low-cost and fast onsite detection method for PFAS in water.

Natural surfactant for sustainable carbon utilization in cleaner production of fossil fuels: Extraction, characterization and application studies

In this study, the extraction, characterization, and performance evaluation of a green surfactant, derived from bio-resource (Fenugreek seeds), is reported for effective carbon utilization in subsurface applications. Several characterization tools such as Fourier-transform infrared spectroscope, ultraviolet–visible spectroscope, methylene blue active substance test, surface tension tests, and scanning electron microscope were used to confirm saponin (surface activity) in synthesized surfactant and suitably compared with the properties of conventional surfactants in literature. The prepared green surfactant exhibited anionic behavior as validated by elemental analysis and adsorption studies. The critical micellar concentration of surfactant was determined by surface tension and electrical conductivity and its value was found to be around 0.2 wt%. Carbon dioxide absorption potential of green surfactant was envisaged by molality tests which confirmed that carbon dioxide absorption rate of surfactant was 7–18% higher than pure water. As a result, the surfactant showed high foam volume (> 40 ml) and foaming stability (8–10 h). The high temperature performance was also better. At 90 °C, carbon dioxide bubbles of larger size were present in sufficient quantity which indicated that foaming potential of surfactant was not severely affected by temperature. During adsorption studies, the green surfactant solution showed a mass-loss of 48–60% on a sandstone surface, which is better than the one of a conventional surfactant. It also showed superior property than conventional surfactants in adsorption isotherm investigations. Thus, the use of these green surfactants in subsurface scenario for carbon utilization and oil recovery from a porous media is recommended.

Effects of chemical absorption on mass transfer from single carbon dioxide bubbles in aqueous sodium hydroxide solution in a vertical pipe

Mass transfer rates kL of single carbon-dioxide bubbles with chemical absorption in a vertical pipe were investigated using aqueous sodium hydroxide solutions. The pH of the solution was varied from 12 to 13.15. The pipe diameter D was 12.5 mm. The bubble diameter d was varied for 0.4 < d/D < 1.4 to cover various bubble shapes. The enhancement factor, E, which is the ratio of kL with and without chemical absorption, was almost unity for pH < 12.25. Then E increased with increasing pH and d for pH > 12.25. Its magnitude was, however, lower than the estimation by the two-film theory. An E correlation was developed. Good estimation of the Sherwood number for bubbles with chemical absorption was obtained by combining the E correlation and the Sherwood number correlations for bubbles without chemical absorption. Applicability of the correlations to bubbles in a larger pipe diameter was also examined.

Analyze open channel for continuously low speed used carbon dioxide bubbles

Designing a recirculating open-channel for continuously low speed in place of a towing tank required checking on its flow characteristics. There are many methods for checking the flow characteristics such as food coloring techniques, using buoys and hydrogen gas bubbles, etc. For this research, we use carbon dioxide bubbles which are caused by the reaction between sodium bicarbonate (NaHCO3) and hydrochloric acid (HCl) that is diluted in water until the acidity is equal to pH 3. Our experiments were carried at the area near the wall and the center of the test range at depths 6, 8 and 10 centimeters from the free surface level respectively. From the experimental results, the trend of water flow patterns in the center of the channel using food coloring needles technique tends to form the fluid flow close to the computational fluid dynamics (CFD) while the results from the carbon dioxide bubble technique are different compared with the two previous techniques by less than 20 percent, and the trends of the water flow pattern results of the numerical method, the food coloring needle, and the carbon dioxide bubble techniques. The tendency of the flow pattern in the same direction.

A mixture model for a dilute dispersion of gas in a liquid flow: Mathematical analysis and application to aluminium electrolysis

A mixture model to take into account the flow of small carbon dioxide bubbles dissolved in a liquid is presented. The model describes the evolution of the velocity fields (mixture and gas), the pressure and the volume fraction of gas. The system of equations is derived from mass and momentum conservation of the mixture and gas.Well-posedness is proved for a simplified problem when the volume fraction of gas is known and small. A priori error estimates are proved for a stabilized finite element approximation.An industrial application pertaining to aluminium electrolysis is presented. Numerical results indicated that the effect of gas bubbles on the flow cannot be neglected.

A model for the fate of carbon dioxide from a simulated carbon storage seep

Offshore geological carbon storage (GCS) is a rapidly developing technology essential for meeting international climate goals. While the likelihood of leakage from a properly planned geological sequestration site is low, assurance that CO2 stays contained will require robust monitoring programs. While seismic imaging methods are used to monitor the geological reservoir, the ideal method for monitoring the water column above the reservoir depends on the fate and transport of CO2. Whether CO2 is likely to be present as a rising seep of bubbles or dissolved in the water column near the seafloor will determine the appropriate monitoring technology and lead to a better understanding of the environmental impact of a potential leak. In this study, high definition video of a laboratory release of a carbon dioxide bubble seep recorded the size distribution of bubbles as a function of flow rate and orifice diameter. The transport of CO2 from different bubble size distributions was then modeled using the Texas A&M Oil Spill Calculator modeling suite. Model results show that the most important factor determining the rise height and transport of CO2 from the simulated leak was the maximum initial bubble size. For a maximum bubble radius of 5 mm, 95% of CO2 in the simulated seep reached a height of 17.1 m above the seafloor. When the maximum bubble radius was limited to 3 mm, 95% of CO2 dissolved by 7.8 m above the seafloor. The modeled results were verified during a controlled release of CO2 in Oslo Fjord.

Determination of Polybrominated Diphenyl Ethers in Water Samples Using Effervescent-Assisted Dispersive Liquid-Liquid Icroextraction with Solidification of the Aqueous Phase.

An effective and sensitive method is necessary for the determination of polybrominated diphenyl ethers (PBDEs) pollutants in water. In this study, effervescent-assisted dispersive liquid-liquid microextraction with solidification of the aqueous phase (EA-DLLME-SAP), followed by Gas Chromatography-Tandem Mass Spectrometry (GC-MS-MS) quantitative analysis, was established for the preconcentration and determination of PBDEs in real environmental water samples. 1,1,2,2-Tetrachloroethane was used as the extractant and directly dispersed into the water phase of the aqueous samples with the aid of a large number of carbon dioxide bubbles generated via the acid-base reaction of acetic acid and sodium bicarbonate, which did not require the use of a dispersant during the extraction process. The key factors affecting the extraction recovery were optimized, and an internal standard was used for quantitative analysis, which gave good linearity ranges of 1–100 ng·L−1 (BDEs 28, 47, 99, and 100), 2–200 ng·L−1 (BDEs 153, 154, and 183) and 5–500 ng·L−1 (BDE 209) with limits of quantification in the range of 1.0–5.0 ng·L−1. The accuracy was verified with relative standard deviations < 8.5% observed in tap, lake, river and reservoir water samples with relative recoveries ranging from 67.2 to 102.6%. The presented method contributes to the determination of PBDEs in environmental water samples.

Extraction of Type I Collagen from Tilapia Scales Using Acetic Acid and Ultrafine Bubbles

Type I collagen is commonly used in medical materials and cosmetics. While it can be extracted from the skin and bones of mammals, marine collagen has attracted attention recently, since the use of mammalian collagen could result in zoonosis, and products containing mammalian collagen are avoided due to some religious beliefs. Chemical extractions using strong acids and alkalis, thermal extractions, and other nonconventional methods have been used for collagen extraction. However, there are few reports on environmentally friendly methods. Although heat extractions provide higher yields of collagen, they often cause collagen denaturation. Therefore, dilute acetic acid and ultrafine bubbles of oxygen, carbon dioxide, and ozone were used to extract type I collagen from tilapia scales. The extraction performance of the different conditions employed was qualitatively analyzed by SDS-PAGE electrophoresis, and the collagen concentration was quantified using circular dichroism spectroscopy by monitoring the peak intensity at 221 nm, which is specific to the triple helix of type I collagen. Collagen was extracted from tilapia scales with a yield of 1.58% by the aeration of ultrafine bubbles of carbon dioxide gas in a 0.1 M acetic acid solution for 5 h.

Carbon Dioxide Bubbles Removal by Capillary Actuation in the Anode Channel of Direct Methanol Fuel Cells

Abstract On the anode side of a direct-methanol fuel cell, carbon dioxide bubbles are generated as a result of the methanol oxidation reaction. The accumulation of such bubbles prevents methanol from reaching the diffusion layer (DL). Hence, a reduction in the reaction rate occurs, which limits the maximum current density of the cell. To keep carbon dioxide bubbles away from the diffusion layer surface, a new design of the anode flow channel besides wall surface treatment is developed. Such a design can introduce capillary actuation, which forces the carbon dioxide bubbles to move away from the diffusion layer due to capillary forces. This can be achieved by using a trapezoidal shape of the flow channel, as well as the combined effect of hydrophilic and hydrophobic surface treatments on the diffusion layer and top wall, respectively. To identify the optimal design of the anode flow channel, a three-dimensional, two-phase flow model is developed. The model is numerically simulated, and the results are validated with available measurements. Results indicated that treating the diffusion layer with a hydrophilic layer increases the area in direct contact with liquid methanol. Besides, the hydrophobic top channel wall makes it easier for the carbon dioxide bubbles to attach and spread out on the top surface. However, super-hydrophobic treatment of the top wall should be avoided, as it can cause difficulty in bubble extraction from the channel. The current findings create a promising opportunity to improve the performance of direct-methanol fuel cells.

Microparticle Effect of Carbon Dioxide Hydrate Crystal Nucleus in Reaction Kettle

This study analyzed the partial effect of carbon dioxide hydrate in reaction kettle experiments. The particle and bubble characteristics of the crystal nucleus during carbon dioxide hydrate decomposition were observed under the microscope. The results showed that in the temperature range of 0.5°C–3.5°C, the pressure range of 3 MPa– 5.5 MPa, phase characteristics in the reaction kettle changed in a complex fashion during carbon dioxide hydrate formation. During hydrate decomposition, numerous carbon dioxide bubbles were produced, mainly by precipitation at high temperatures or in the hydrate cage structure. The hydrate crystal nucleus initially exhibited fluidity in the reaction. However, as the reaction progressed, the hydrate crystal nucleus migrated upward under the influence of gravity and carbon dioxide diffused into the aqueous phase. Next, the hydrate was formed and accumulated, finally forming a solid carbon dioxide hydrate layer.

Effective Eradication of Tumors by Enhancing Photoacoustic‐Imaging‐Guided Combined Photothermal Therapy and Ultrasonic Therapy

AbstractExploiting a comprehensive strategy that processes diagnosis and therapeutic functions is desired for eradicating tumors. In this study, two versatile nanoparticles are introduced: one is polyethylene glycol‐ and polyethyleneimine‐modified gold nanorods (mPEG–PEI–AuNRs), and the other is formed by electrostatic interactions between mPEG–PEI and calcium carbonate nanoparticles (mPEG–PEI/CaNPs). These two nanoparticles possess following favorable properties: 1) mPEG–PEI–AuNRs and mPEG–PEI/CaNPs show not only high cell uptake in acidic tumoral pH, but also efficient accumulation in tumors with prolonged circulation. 2) mPEG–PEI/CaNPs can generate carbon dioxide (CO2) bubbles in acidic tumoral environment and the photoacoustic (PA) signals from mPEG–PEI–AuNRs can be enhanced with the generation of CO2 bubbles. 3) The tumors can be eradicated by combining photothermal therapy (PTT) with ultrasonic therapy (UST) under the near‐infrared (NIR) laser and ultrasonic irradiation with the presence of mPEG–PEI–AuNRs and CO2 bubbles from mPEG–PEI/CaNPs. The detailed evaluation of cellular uptake, photothermal property of mPEG–PEI–AuNRs, CO2 bubbles’ generation from mPEG–PEI/CaNPs, imaging, and combined PTT and UST are carried out in vitro or in vivo. This work has great potential usage for diagnosis and treatment in the future.

Feature Analysis, Tracking, and Data Reduction: An Application to Multiphase Reactor Simulation MFiX-Exa for In-Situ Use Case

As we enter the exascale computing regime, powerful supercomputers continue to produce much higher amounts of data than what can be stored for offline data processing. To utilize such high compute capabilities on these machines, much of the data processing needs to happen in situ, when the full high-resolution data is available at the supercomputer memory. In this article, we discuss our MFiX-Exa simulation, which models multiphase flow by tracking a very large number of particles through the simulation domain. In one of the use cases, the carbon particles interact with air to produce carbon dioxide bubbles from the reactor. These bubbles are of primary interest to the domain experts for these simulations. For this particle-based simulation, we propose a streaming technique that can be deployed in situ to efficiently identify the bubbles, track them over time, and use them to down-sample the data with minimal loss in these features.

Analysis on Geometry of Fluid Flow Manifold in Direct Methanol Fuel Cell

Fuel cells are the devices that convert chemical energy into electrical energy through an electrochemical reaction. Direct Methanol Fuel cell (DMFC) is a proton exchange membrane fuel cells in which methanol is used as fuel. Its high energy density makes it suitable for fuel cells. Even though carbon dioxide is produced, there is no production of sulfur or nitrogen oxides. The problems usually occurred while working with DMFC are methanol crossover, condensation of methanol, water management and carbon dioxide release. In that the uneven flow distribution, accumulation of carbon dioxide bubbles in the fuel cell are the major issues in DMFC. To prevent these issues, this work focuses on the theoretical and experimental studies on development of fuel cells with special importance to geometry of the manifold. This paper provides the optimal solution for preventing uneven flow distribution that is the usage of squoval shaped manifold which is the combination of both square and circle. Performance of DMFC with squoval shape manifold is evaluated experimentally and is compared with square shape manifold and rectangle shape manifold geometry design.

Analysis on Geometry of Fluid Flow Manifold in Direct Methanol Fuel Cell

Fuel cells are the devices that convert chemical energy into electrical energy through an electrochemical reaction. Direct Methanol Fuel cell (DMFC) is a proton exchange membrane fuel cells in which methanol is used as fuel. Its high energy density makes it suitable for fuel cells. Even though carbon dioxide is produced, there is no production of sulfur or nitrogen oxides. The problems usually occurred while working with DMFC are methanol crossover, condensation of methanol, water management and carbon dioxide release. In that the uneven flow distribution, accumulation of carbon dioxide bubbles in the fuel cell are the major issues in DMFC. To prevent these issues, this work focuses on the theoretical and experimental studies on development of fuel cells with special importance to geometry of the manifold. This paper provides the optimal solution for preventing uneven flow distribution that is the usage of squoval shaped manifold which is the combination of both square and circle. Performance of DMFC with squoval shape manifold is evaluated experimentally and is compared with square shape manifold and rectangle shape manifold geometry design.

Bubble-free System for Belousov-Zhabotinsky Gels

The chemical energy from the Belousov-Zhabotinsky (BZ) reaction powers autonomous mechanical oscillations in BZ gels. One drawback is that the process produces carbon dioxide bubbles, making length...

Multimodal chemo-/magneto-/phototaxis of 3G CNT-bots to power fuel cells

We report the development of a 3G microswimmer, namely, CNT-bot, capable of undergoing acid-, alkali-, magneto- and phototaxis inside acidic or alkaline baths of peroxide fuel and/or water. The use of carboxyl-functionalised multi-walled carbon nanotubes (MWCNTs) facilitated the propulsion of CNT-bots in an alkaline-water solution by ejecting carbon-dioxide bubbles. Furthermore, doping of magnetite nanoparticles (FeONPs), ferrous ions (Fe2+) and titanium dioxide nanoparticles (TiONPs) induces magnetic, chemical and photonic modes of propulsion. While FeONPs stimulated magnetotaxis at a rate of up to ~10 body lengths per second under the influence of a bar magnet, chemotaxis of a similar speed in a peroxide fuel was achieved by bubble-propulsion of oxygen gas originating from the Fenton reaction. In addition, the light-stimulated photo-Fenton reaction led to phototaxis of CNT-bots. A thin coating of magnesium imparted a half-faced Janus appearance to the CNT-bots, which facilitated motion in normal or acidic water media through the ejection of hydrogen gas bubbles. This chemotaxis could be transformed into pH-stimulated directional motion by establishing an acid or alkali concentration gradient across the peroxide and/or water baths. The capacity of CNT-bots to produce oxygen (hydrogen) bubbles in peroxide (acidic water) fuel was exploited to power a PEM fuel cell to generate electricity. The pure oxygen and hydrogen gases generated by CNT-bots in separate chambers were fed directly into the fuel cell in which the incessant motions of the particle facilitated the creation and release of the pure gases to achieve on-demand electricity generation. The motor could also induce dye degradation through advanced oxidation owing to the production of intermediate hydroxyl radicals during the Fenton reaction.

Magnetic effervescence tablet-assisted switchable hydrophilicity solvent-based liquid phase microextraction of triazine herbicides in water samples

Abstract A method for the determination of triazine herbicides in water samples was established by magnetic effervescence tablet-assisted switchable hydrophilicity solvent-based liquid phase microextraction procedure (META-SHS-LPME) coupled with high-performance liquid chromatography with diode array detection. The magnetic effervescence tablet, composed of citric acid, sodium hexanoate, sodium bicarbonate, and Fe3O4 nanoparticles, combined extractant generation, dispersion, and magnetic recovery into one step. Citric acid could react with sodium hexanoate and sodium bicarbonate to generate hexanoic acid and carbon dioxide in situ, respectively. Carbon dioxide bubbles assisted the eco-friendly extractant hexanoic acid to fully contact with target compounds. Fe3O4 nanoparticles containing extractant and triazine herbicides were isolated from the sample solution using an external magnet. Good linearity was achieved in the range of 50–5000 ng mL−1 with a correlation coefficient greater than 0.997. The limit of detection was within 0.10–0.13 ng mL−1. The extraction recovery of triazine herbicides were 81.4–96.7% in well, pond, and river waters. Overall, the proposed method was a simple, efficient, and eco-friendly analytical approach for determining triazine herbicide residues in water samples.