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Mokudai T, Kawada M, Tadaki D, Hirano-Iwata A, Kanetaka H, Fujimori H, Takemoto E, Niwano M. Radical generation and bactericidal activity of nanobubbles produced by ultrasonic irradiation of carbonated water. ULTRASONICS SONOCHEMISTRY 2024; 103:106809. [PMID: 38364483 PMCID: PMC10879770 DOI: 10.1016/j.ultsonch.2024.106809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 02/04/2024] [Accepted: 02/13/2024] [Indexed: 02/18/2024]
Abstract
Our previous study showed that nanobubbles (NBs) encapsulating CO2 gas have bactericidal activity due to reactive oxygen species (ROS) (Yamaguchi et al., 2020). Here, we report that bulk NBs encapsulating CO2 can be efficiently generated by ultrasonically irradiating carbonated water using a piezoelectric transducer with a frequency of 1.7 MHz. The generated NBs were less than 100 nm in size and had a lifetime of 500 h. Furthermore, generation of ROS in the NB suspension was investigated using electron spin resonance spectroscopy and fluorescence spectrometry. The main ROS was found to be the hydroxyl radical, which is consistent with our previous observations. The bactericidal activity lasted for at least one week. Furthermore, a mist generated by atomizing the NB suspension with ultrasonic waves was confirmed to have the same bactericidal activity as the suspension itself. We believe that the strong, persistent bactericidal activity and radical generation phenomenon are unique to NBs produced by ultrasonic irradiation of carbonated water. We propose that entrapped CO2 molecules strongly interact with water at the NB interface to weaken the interface, and high-pressure CO2 gas erupts from this weakened interface to generate ROS with bactericidal activity.
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Affiliation(s)
- Takayuki Mokudai
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan; Joining and Welding Research Institute, Osaka University, Osaka 567-0047, Japan
| | - Michi Kawada
- Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan
| | - Daisuke Tadaki
- Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
| | - Ayumi Hirano-Iwata
- Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
| | - Hiroyasu Kanetaka
- Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan
| | - Hiroshi Fujimori
- Planning & Development Department, Takemoto Yohki Co., Ltd., Tokyo 111-0036, Japan
| | - Emiko Takemoto
- Planning & Development Department, Takemoto Yohki Co., Ltd., Tokyo 111-0036, Japan
| | - Michio Niwano
- Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan; Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan.
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Le KCM, Tran ATQ, Vu MP, Duong PVQ, Nguyen KT. Preventing Static Biofilm Formation of Staphylococcus aureus on Different Types of Surfaces Using Microbubbles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:1698-1706. [PMID: 38198688 DOI: 10.1021/acs.langmuir.3c02773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Bacterial fouling and biofilm formation on surfaces have been ongoing problems in real life as well as in the medical field. Different approaches have been taken to tackle the issues, from costly surface modification to antibiotic-delivering strategies. In this study, we examined the potential of using stabilized microbubbles (MBs) to shield against bacterial adhesion. Three types of surfaces were tested: hydrophilic glass (hydrophilic surface), neutral hydrophobic polystyrene (PS)-coated surfaces, and negatively charged hydrophobic octadecyltrichlorosilane (OTS)-coated surfaces. By evaluating the colony-forming unit (CFU) values from each surface, MBs stabilized by 0.05 mM SDS were shown to only produce significant reduction of Staphylococcus aureus adhesion on PS surfaces, up to 60.29 and 82.32% compared to no-MB PS surfaces, and no-MB uncoated surfaces, correspondingly, due to the appropriate size, stability, and negative charges of the MB shielding layer. On the other hand, OTS coatings had an intrinsic antiadhesion effect (69.83% compared to uncoated surface), given that the negatively charged OTS-aqueous interface or surface porosity nature of the coating prohibited the attachment of MBs, leading to the elimination of the antifouling effect of MBs. Ultimately, MBs gave better shielding results than surface modification when compared to uncoated surfaces and hence can be applied more widely.
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Affiliation(s)
- Khoa C M Le
- School of Biotechnology, International University, Vietnam National University, Ho Chi Minh City 700000, Viet Nam
| | - Anh T Q Tran
- School of Biotechnology, International University, Vietnam National University, Ho Chi Minh City 700000, Viet Nam
| | - Mai P Vu
- School of Biotechnology, International University, Vietnam National University, Ho Chi Minh City 700000, Viet Nam
| | - Phuong V Q Duong
- School of Biotechnology, International University, Vietnam National University, Ho Chi Minh City 700000, Viet Nam
| | - Khoi T Nguyen
- School of Biotechnology, International University, Vietnam National University, Ho Chi Minh City 700000, Viet Nam
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Vu MP, Le Hanh Tran N, Lam TQ, Quynh Tran AT, Anh Le TP, Nguyen KT. Investigating the effects of ultrafine bubbles on bacterial growth. RSC Adv 2024; 14:2159-2169. [PMID: 38205233 PMCID: PMC10777100 DOI: 10.1039/d3ra07454d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 12/28/2023] [Indexed: 01/12/2024] Open
Abstract
Several previous studies have considered ultrafine bubbles as a potential research target because their properties can be applied in many different research areas. In particular, the interaction between UFBs and microorganisms has always been one of the aspects that receives much attention due to the high difficulty in controlling a living system. The properties of UFBs, as mobile air-water interfaces, are greatly determined by their gas cores which play a critical role in regulating microbial growth. This study aims to investigate the effects of ultrafine bubbles on bacterial growth. Two well-studied organisms were chosen as models - Escherichia coli and Staphylococcus aureus. Their growing behavior was examined based on the growth rate, phenotype and biomass. Three types of Luria-Bertani cultures were tested, including a standard culture containing distilled water, an air ultrafine bubble culture, and a hydrogen ultrafine bubble culture. The UFBs were generated via ultrasonic cavitation and stabilized by 50 μM SDS, which was proven to have negligible effects on bacterial growth. By comparing among the three cultivation conditions, the bacterial growth rates were observed to be the highest in exposure to HUFBs. The results also signified that UFBs had an enhancement on cell proliferation. On the other hand, while proposing an increase in cell density, bacteria cultured in HUFB media have their sizes decreased uniformly and significantly (p-value < 0.05). This study confirmed that bacterial growth was promoted by UFBs; and better effects recorded were due to the HUFB present in the culture media. However, the average morphological size of bacteria was in negative correlation with their population size.
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Affiliation(s)
- Mai Phuong Vu
- School of Biotechnology, International University, Vietnam National University Ho Chi Minh City 700000 Vietnam +84 28 3724 4271 +84 28 3724 4270
| | - Nguyen Le Hanh Tran
- School of Biotechnology, International University, Vietnam National University Ho Chi Minh City 700000 Vietnam +84 28 3724 4271 +84 28 3724 4270
| | - Thien Quang Lam
- School of Biotechnology, International University, Vietnam National University Ho Chi Minh City 700000 Vietnam +84 28 3724 4271 +84 28 3724 4270
| | - Anh Thi Quynh Tran
- School of Biotechnology, International University, Vietnam National University Ho Chi Minh City 700000 Vietnam +84 28 3724 4271 +84 28 3724 4270
| | - Thu Phan Anh Le
- School of Biotechnology, International University, Vietnam National University Ho Chi Minh City 700000 Vietnam +84 28 3724 4271 +84 28 3724 4270
| | - Khoi Tan Nguyen
- School of Biotechnology, International University, Vietnam National University Ho Chi Minh City 700000 Vietnam +84 28 3724 4271 +84 28 3724 4270
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Niwano M, Ma T, Iwata K, Tadaki D, Yamamoto H, Kimura Y, Hirano-Iwata A. Two-dimensional water-molecule-cluster layers at nanobubble interfaces. J Colloid Interface Sci 2023; 652:1775-1783. [PMID: 37678082 DOI: 10.1016/j.jcis.2023.08.173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 08/18/2023] [Accepted: 08/27/2023] [Indexed: 09/09/2023]
Abstract
HYPOTHESIS Bulk nanobubbles (NBs) have high surface charge densities and long lifetimes. Despite several attempts to understand the lifetime of NBs, their interfacial layer structure remains unknown. It is hypothesized that a specific interfacial layer exists with a hydrogen bond network that stabilizes NBs. EXPERIMENTS In situ infrared reflectance-absorption spectroscopy and density functional theory were used to determine the interfacial layer structure of NBs. Furthermore, nuclear magnetic resonance spectroscopy was used to examine the interfacial layer hardness of bubbles filled with N2, O2, and CO2, which was expected to depend on the encapsulated gas species. FINDINGS The interfacial layer was composed of three-, four-, and five-membered ring clusters of water molecules. An interface model was proposed in which a two-dimensional layer of clusters with large electric dipole moments is oriented toward the endohedral gas, and the hydrophobic surface is adjacent to the free water. The interfacial layer hardness was dependent on the interaction with the gas (N2 > O2 > CO2), which supports the proposed interface model. These findings can be generalized to the structure of water at gas-water interfaces.
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Affiliation(s)
- Michio Niwano
- Laboratory for Nano-electronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Miyagi 980-8577, Japan.
| | - Teng Ma
- Advanced Institute for Materials Research (AIMR), Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Kazuki Iwata
- Faculty of Comprehensive Management, Tohoku Fukushi University, Sendai, Miyagi 989-3201, Japan
| | - Daisuke Tadaki
- Laboratory for Nano-electronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Hideaki Yamamoto
- Laboratory for Nano-electronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Yasuo Kimura
- Department of Electric and Electronic Engineering, Tokyo University of Technology, Hachioji, Tokyo 192-0983, Japan
| | - Ayumi Hirano-Iwata
- Laboratory for Nano-electronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Miyagi 980-8577, Japan; Faculty of Comprehensive Management, Tohoku Fukushi University, Sendai, Miyagi 989-3201, Japan
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Prakash R, Lee J, Moon Y, Pradhan D, Kim SH, Lee HY, Lee J. Experimental Investigation of Cavitation Bulk Nanobubbles Characteristics: Effects of pH and Surface-Active Agents. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:1968-1986. [PMID: 36692411 DOI: 10.1021/acs.langmuir.2c03027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Nanobubbles (NBs) have a widespread application in antimicrobial activity, wastewater treatment, and ecological restoration due to numerous peculiar characteristics, such as small diameter, long-term stability, and ability to produce hydroxyl radicals. Despite significant applications, only limited comprehensive investigations are available on the role of surfactants and pH in NBs characteristics. Therefore, this study examines the effects of different surfactants (i.e., anionic, cationic, and nonionic) and pH medium on bulk NB formation, diameter, concentration, bubble size distribution (BSD), ζ-potential, and stability. The effect of surfactant at concentrations above and below the critical micelle concentration was investigated. NBs were generated in deionized (DI) water using a piezoelectric transducer. The stability of NBs was assessed by tracking the variation in diameter and concentration over time. In a neutral medium, the diameter of NBs is smaller than in other surfactant or pH mediums. The diameter, concentration, BSD, and stability of NBs are strongly influenced by the ζ-potential rather than the solution medium. BSD curve shifts to a smaller bubble diameter when the magnitude of ζ-potential is high in any solution. In pure water, surfactant, and pH mediums, NBs have existed for a long time. NBs have a shorter life span in environments with a pH ≤ 3. Surfactant adsorption on the surface of NBs increases with increasing surfactant concentration up to a certain limit, beyond which it declines substantially. The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was used to interpret the NBs stability, resulting in a total potential energy barrier that is positive and greater than 45.55 kBT for 6 ≤ pH ≤ 11, whereas for pH < 6, the potential energy barrier essentially vanishes. Moreover, an effort has also been made to explicate the plausible prospect of ion distribution and its alignment surrounding NBs in cationic and anionic surfactants. This study will extend the in-depth investigation of NBs for industrial applications involving NBs.
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Affiliation(s)
- Ritesh Prakash
- Microfluidic Convergence Laboratory, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon16419, Republic of Korea
| | - Jinseok Lee
- Microfluidic Convergence Laboratory, School of Mechanical Engineering, Sungkyunkwan University, Suwon16419, Republic of Korea
| | - Youngkwang Moon
- Microfluidic Convergence Laboratory, School of Mechanical Engineering, Sungkyunkwan University, Suwon16419, Republic of Korea
| | - Diva Pradhan
- Microfluidic Convergence Laboratory, School of Mechanical Engineering, Sungkyunkwan University, Suwon16419, Republic of Korea
| | - Seung-Hyun Kim
- School of Engineering, Brown University, Providence, Rhode Island02912, United States
| | - Ho-Yong Lee
- Department of Material Science and Engineering, Sunmoon University, Asan31460, Republic of Korea
| | - Jinkee Lee
- Microfluidic Convergence Laboratory, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon16419, Republic of Korea
- Microfluidic Convergence Laboratory, School of Mechanical Engineering, Sungkyunkwan University, Suwon16419, Republic of Korea
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Yin Y, Shen H. Common methods in mitochondrial research (Review). Int J Mol Med 2022; 50:126. [PMID: 36004457 PMCID: PMC9448300 DOI: 10.3892/ijmm.2022.5182] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 08/09/2022] [Indexed: 01/18/2023] Open
Affiliation(s)
- Yiyuan Yin
- Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Haitao Shen
- Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
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Ulatowski K, Wierzchowski K, Fiuk J, Sobieszuk P. Effect of Nanobubble Presence on Murine Fibroblasts and Human Leukemia Cell Cultures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:8575-8584. [PMID: 35776689 PMCID: PMC9301908 DOI: 10.1021/acs.langmuir.2c00819] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Nanobubbles can enhance both the proliferation and metabolic activity of microorganisms (mainly bacteria) and the growth of the whole higher organisms such as mice, fish, or plants. The critical fact is that nanobubbles of different gases can affect given cells differently. As animal cell cultures are used in industry and research studies, investigations of their interactions with nanobubbles should be carried out. This study aims to uncover whether the presence of nanobubbles improves the proliferation rate and metabolic activity of L929 fibroblasts and HL60 leukemia cells as exemplary animal cell lines of adherent and non-adherent cells, respectively. The long-term (8-day) cultures of both L929 and HL-60 cells with nanobubble addition to the appropriate medium were carried out. The medium was not exchanged for the whole duration of the culture. Nanobubbles of two gases - oxygen and nitrogen - were dispersed in the appropriate media and then used to culture cells. The density and viability of cells were assessed microscopically while their metabolic activity was determined using PrestoBlue or XTT assays. Additionally, we have performed the analysis of substrate consumption rate during the growth and activity of lactate dehydrogenase. We have shown that nanodispersion of both gases enhances the proliferation rate and metabolic activity of L929. For HL-60 cultures, reference cultures exhibited better viability, cell density, and metabolic activity than those with either oxygen or nitrogen nanobubbles. Obtained results clearly show that nanobubble dispersions of both oxygen and nitrogen positively affect the cultures of L929 while inhibiting the growth of HL-60 cells. We suspect that a similar positive effect would be visible for other adherent cells, similar to L929. Such results are promising for intensifying the growth of animal or human cells in routine cell cultures.
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Li P, Wang J, Liao Z, Ueda Y, Yoshikawa K, Zhang G. Microbubbles for Effective Cleaning of Metal Surfaces Without Chemical Agents. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:769-776. [PMID: 34985892 DOI: 10.1021/acs.langmuir.1c02769] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Traditional cleaning methods involving surfactants and ultrasound generate large amounts of wastewater. Microbubbles offer a more eco-friendly technology for interface cleaning. Here, we explored the efficiency of microbubbles for cleaning oil from metal surfaces. Air microbubbles at concentrations as high as 106 particles/mL were generated by hydrodynamic cavitation. Under optimal conditions, cleaning efficiencies for the removal of oil from carbon-steel and stainless-steel surfaces were 78.5 and 49.8% after 15 min, respectively, compared to only 6.5 and 9.9% without microbubbles. Additionally, combining microbubble treatment with the ultrasonic method achieved a higher efficiency than ultrasonic cleaning alone, achieving an efficiency of 85.5% after 3 min compared to 69.0%. The mechanism of microbubble cleaning was determined using a fluorescence observation system, and a model was established to describe the cleaning process. The use of microbubbles produced less emulsified oil wastewater because the oil that attaches to the microbubble surface floats with the bubbles to the surface of the cleaning water, where it can be removed, allowing for water recycling. This novel microbubble cleaning technology, which both enhances cleaning efficiency and reduces wastewater production, represents a viable and eco-friendly option for degreasing processes.
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Affiliation(s)
- Pan Li
- School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, P. R. China
- School of Environmental Science and Engineering, State Key Laboratory of Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
| | - JiaHao Wang
- School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, P. R. China
| | - ZhengHao Liao
- School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, P. R. China
| | - Yoshikatsu Ueda
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 6110011, Japan
| | - Kiyoshi Yoshikawa
- Institute of Advanced Energy, Kyoto University, Sakyo, Kyoto 6068501, Japan
| | - GuoXing Zhang
- Gubei International Fortune Center, Shanghai Challenge Textile Co., Ltd., RM303, 1438 Hongqiao Road, Changning District, Shanghai 201504, P. R. China
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MORISHITA RISAKO, ITOH SATOSHI, TAKEDA-MORISHITA MARIKO. Evaluation of Bactericidal Effects of H<sub>2</sub>- and O<sub>3</sub>-filled Ultrafine Bubbles Water. Biocontrol Sci 2022; 27:139-142. [DOI: 10.4265/bio.27.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
| | - SATOSHI ITOH
- The Faculty of Nutrition, Kobe Gakuin University
| | - MARIKO TAKEDA-MORISHITA
- Laboratory of Drug Delivery Systems, Faculty of Pharmaceutical Sciences, Kobe Gakuin University
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Antonio Cerrón-Calle G, Luna Magdaleno A, Graf JC, Apul OG, Garcia-Segura S. Elucidating CO 2 nanobubble interfacial reactivity and impacts on water chemistry. J Colloid Interface Sci 2021; 607:720-728. [PMID: 34536932 DOI: 10.1016/j.jcis.2021.09.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/04/2021] [Accepted: 09/06/2021] [Indexed: 11/28/2022]
Abstract
HYPOTHESIS Carbon dioxide nanobubbles can increase effective gas-transfer to solution and enhance buffering capacity given the stable suspension in water of CO2 gas within nanobubbles and the existence of larger gas/water interface. EXPERIMENTS The physico-chemical properties and responses of CO2 nanobubbles were recorded at different generation times (10, 30, 50, and 70 min) and benchmarked against traditional macrobubbles of CO2 for the same amount of delivered gas. Effective concentration of CO2 was evaluated by measuring the buffer capacity (β). The size distribution of nanobubbles during the experiments was measured by Nanoparticle Track Analysis. FINDINGS The mass transfer coefficient (KLa) showed a dramatically increase by 11-fold for the same volume of gas delivered when using nanobubbles. The β values obtained for nanobubbles were 7 times higher than that of traditional bubbles which can lead to significant source of CO2 availability by using the nanobubble method. Nanobubbles, consequently, undergo mass loss at higher pH corresponding to mass transfer process due to concentration gradient at the surrounding nanobubbles. This is the first report of CO2 nanobubbles buffer capacity evaluation.
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Affiliation(s)
- Gabriel Antonio Cerrón-Calle
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ 85287-3005, USA
| | - Andre Luna Magdaleno
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ 85287-3005, USA
| | - John C Graf
- NASA Johnson Space Center, Houston 77058, TX, United States
| | - Onur G Apul
- Department of Civil and Environmental Engineering, University of Maine, Orono 04469, ME, United States
| | - Sergi Garcia-Segura
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ 85287-3005, USA.
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