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Nilouyal S, Karahan HE, Isfahani AP, Yamaguchi D, Gibbons AH, Ito MMM, Sivaniah E, Ghalei B. Carbonic Anhydrase-Mimicking Supramolecular Nanoassemblies for Developing Carbon Capture Membranes. ACS Appl Mater Interfaces 2022; 14:37595-37607. [PMID: 35969637 DOI: 10.1021/acsami.2c06270] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
As a ubiquitous family of enzymes with high performance in converting carbon dioxide (CO2) into bicarbonate, carbonic anhydrases (CAs) sparked enormous attention for carbon capture. Nevertheless, the high cost and operational instability of CAs hamper their practical relevance, and the utility of CAs is mainly limited to aqueous applications where CO2-to-bicarbonate conversion is possible. Taking advantage of the chemical motif that endows CA-like active sites (metal-coordinated histidine), here we introduce a new line of high-performance gas separation membranes with CO2-philic behavior. We first self-assembled a histidine-based bolaamphiphile (His-Bola) molecule in the aqueous phase and coordinated the resulting entities with divalent zinc. Optimizing the supramolecular synthesis conditions ensured that the resultant nanoparticles (His-NPs) exhibit high CO2 affinity and catalytic activity. We then exploited the His-NPs as nanofillers to enhance the separation performance of Pebax MH 1657. The hydrogen-bonding interactions allowed the dispersion of His-NPs within the polymer matrix uniformly, as confirmed by microscopic, spectroscopic, and thermal analyses. The imidazole and amine functionalities of His-NPs enhanced the solubility of CO2 molecules in the polymer matrix. The CA-mimic active sites of His-NPs nanozymes, on the other hand, catalyzed the reversible hydration of CO2 molecules in humid conditions, facilitating their transport across the membranes. The resulting nanocomposite membranes displayed excellent CO2 separation performance, with a high level of stability. At a filling ratio as low as 3 wt %, we achieved a CO2 permeability of >145 Barrer and a CO2/N2 selectivity of >95 with retained performance under humid continuous gas feeds. The bio-inspired approach presented in this work offers a promising platform for designing durable and highly selective CO2 capture membranes.
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Affiliation(s)
- Somaye Nilouyal
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
| | - H Enis Karahan
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
- Synthetic Fuels & Chemicals Technology Center (ITU-SENTEK), Istanbul Technical University, Maslak, 34469 Istanbul, Turkey
| | - Ali Pournaghshband Isfahani
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
| | - Daisuke Yamaguchi
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
| | - Andrew H Gibbons
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
| | - Masateru M M Ito
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
| | - Easan Sivaniah
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
| | - Behnam Ghalei
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, 606-8501 Kyoto, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-Ku, 615-8510 Kyoto, Japan
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Qin D, Gibbons AH, Ito MM, Parimalam SS, Jiang H, Enis Karahan H, Ghalei B, Yamaguchi D, Pandian GN, Sivaniah E. Structural colour enhanced microfluidics. Nat Commun 2022; 13:2281. [PMID: 35589687 PMCID: PMC9120135 DOI: 10.1038/s41467-022-29956-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 04/08/2022] [Indexed: 01/11/2023] Open
Abstract
Advances in microfluidic technology towards flexibility, transparency, functionality, wearability, scale reduction or complexity enhancement are currently limited by choices in materials and assembly methods. Organized microfibrillation is a method for optically printing well-defined porosity into thin polymer films with ultrahigh resolution. Here we demonstrate this method to create self-enclosed microfluidic devices with a few simple steps, in a number of flexible and transparent formats. Structural colour, a property of organized microfibrillation, becomes an intrinsic feature of these microfluidic devices, enabling in-situ sensing capability. Since the system fluid dynamics are dependent on the internal pore size, capillary flow is shown to become characterized by structural colour, while independent of channel dimension, irrespective of whether devices are printed at the centimetre or micrometre scale. Moreover, the capability of generating and combining different internal porosities enables the OM microfluidics to be used for pore-size based applications, as demonstrated by separation of biomolecular mixtures.
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Affiliation(s)
- Detao Qin
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Andrew H Gibbons
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Masateru M Ito
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan.
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan.
| | | | - Handong Jiang
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - H Enis Karahan
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Behnam Ghalei
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Daisuke Yamaguchi
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Ganesh N Pandian
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Easan Sivaniah
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan.
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan.
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Karahan HE, Ji M, Pinilla JL, Han X, Mohamed A, Wang L, Wang Y, Zhai S, Montoya A, Beyenal H, Chen Y. Biomass-derived nanocarbon materials for biological applications: challenges and prospects. J Mater Chem B 2020; 8:9668-9678. [PMID: 33000843 DOI: 10.1039/d0tb01027h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Biomass-derived nanocarbons (BNCs) have attracted significant research interests due to their promising economic and environmental benefits. Following their extensive uses in physical and chemical research domains, BNCs are now growing in biological applications. However, their practical biological applications are still in their infancy, requiring critical evaluations and strategic directions, which are provided in this review. The carbonization of biomass sources and major types of BNCs are introduced, encompassing carbon nanodots, nanofibres, nanotubes, and graphenes. Next, essential biological uses of BNCs, antibacterial/antibiofilm materials (nanofibres and nanodots) and bioimaging agents (predominantly nanodots), are summarized. Furthermore, the future potential of BNCs, for designing wound dressing/healing materials, water and air disinfection platforms, and microbial electrochemical systems, is discussed. We reach the conclusion that a crucial challenge is the structural control of BNCs. Furthermore, a key knowledge gap for realizing practical biological applications is the lack of systematic comparisons of BNCs with nanocarbons of synthetic origin in the current literature. Although we did not attempt to perform an exhaustive literature survey, the evaluation of the existing results indicates that BNCs are promising as easily accessible materials for various biomedically and environmentally relevant applications.
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Affiliation(s)
- H Enis Karahan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore.
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Samarasinghe SASC, Chuah CY, Karahan HE, Sethunga GSMDP, Bae TH. Enhanced O 2/N 2 Separation of Mixed-Matrix Membrane Filled with Pluronic-Compatibilized Cobalt Phthalocyanine Particles. Membranes (Basel) 2020; 10:E75. [PMID: 32325765 PMCID: PMC7231378 DOI: 10.3390/membranes10040075] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/16/2020] [Accepted: 04/16/2020] [Indexed: 11/18/2022]
Abstract
Membrane-based air separation (O2/N2) is of great importance owing to its energy efficiency as compared to conventional processes. Currently, dense polymeric membranes serve as the main pillar of industrial processes used for the generation of O2- and N2-enriched gas. However, conventional polymeric membranes often fail to meet the selectivity needs owing to the similarity in the effective diameters of O2 and N2 gases. Meanwhile, mixed-matrix membranes (MMMs) are convenient to produce high-performance membranes while keeping the advantages of polymeric materials. Here, we propose a novel MMM for O2/N2 separation, which is composed of Matrimid® 5218 (Matrimid) as the matrix, cobalt(II) phthalocyanine microparticles (CoPCMPs) as the filler, and Pluronic® F-127 (Pluronic) as the compatibilizer. By the incorporation of CoPCMPs to Matrimid, without Pluronic, interfacial defects were formed. Pluronic-treated CoPCMPs, on the other hand, enhanced O2 permeability and O2/N2 selectivity by 64% and 34%, respectively. We explain the enhancement achieved with the increase of both O2 diffusivity and O2/N2 solubility selectivity.
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Affiliation(s)
- S. A. S. C. Samarasinghe
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; (S.A.S.C.S.); (C.Y.C.); (H.E.K.); (G.S.M.D.P.S.)
- Interdisciplinary Graduate School, Nanyang Technological University, Singapore 637335, Singapore
| | - Chong Yang Chuah
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; (S.A.S.C.S.); (C.Y.C.); (H.E.K.); (G.S.M.D.P.S.)
| | - H. Enis Karahan
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; (S.A.S.C.S.); (C.Y.C.); (H.E.K.); (G.S.M.D.P.S.)
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - G. S. M. D. P. Sethunga
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; (S.A.S.C.S.); (C.Y.C.); (H.E.K.); (G.S.M.D.P.S.)
- Interdisciplinary Graduate School, Nanyang Technological University, Singapore 637335, Singapore
| | - Tae-Hyun Bae
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; (S.A.S.C.S.); (C.Y.C.); (H.E.K.); (G.S.M.D.P.S.)
- Department of Chemical and Biomedical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-338, Korea
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Nie L, Goh K, Wang Y, Lee J, Huang Y, Karahan HE, Zhou K, Guiver MD, Bae TH. Realizing small-flake graphene oxide membranes for ultrafast size-dependent organic solvent nanofiltration. Sci Adv 2020; 6:eaaz9184. [PMID: 32494655 PMCID: PMC7182426 DOI: 10.1126/sciadv.aaz9184] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 01/27/2020] [Indexed: 05/05/2023]
Abstract
Membranes for organic solvent nanofiltration (OSN) or solvent-resistant nanofiltration (SRNF) offer unprecedented opportunities for highly efficient and cost-competitive solvent recovery in the pharmaceutical industry. Here, we describe small-flake graphene oxide (SFGO) membranes for high-performance OSN applications. Our strategy exploits lateral dimension control to engineer shorter and less tortuous transport pathways for solvent molecules. By using La3+ as a cross-linker and spacer for intercalation, the SFGO membrane selective layer was stabilized, and size-dependent ultrafast selective molecular transport was achieved. The methanol permeance was up to 2.9-fold higher than its large-flake GO (LFGO) counterpart, with high selectivity toward three organic dyes. More importantly, the SFGO-La3+ membrane demonstrated robust stability for at least 24 hours under hydrodynamic stresses that are representative of realistic OSN operating conditions. These desirable attributes stem from the La3+ cross-linking, which forms uniquely strong coordination bonds with oxygen-containing functional groups of SFGO. Other cations were found to be ineffective.
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Affiliation(s)
- Lina Nie
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Kunli Goh
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Yu Wang
- Environmental Process Modelling Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Jaewoo Lee
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Yinjuan Huang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - H. Enis Karahan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Kun Zhou
- Environmental Process Modelling Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Michael D. Guiver
- State Key Laboratory of Engines, School of Mechanical Engineering, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
- Corresponding author. (M.D.G.); (T.-H.B.)
| | - Tae-Hyun Bae
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Department of Chemical and Biomedical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-338, Republic of Korea
- Corresponding author. (M.D.G.); (T.-H.B.)
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Zhai S, Karahan HE, Wang C, Pei Z, Wei L, Chen Y. 1D Supercapacitors for Emerging Electronics: Current Status and Future Directions. Adv Mater 2020; 32:e1902387. [PMID: 31304998 DOI: 10.1002/adma.201902387] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 05/17/2019] [Indexed: 06/10/2023]
Abstract
1D supercapacitors (SCs) have emerged as promising candidates to power emerging electronics in recent years because of their unique advantages in energy storage and mechanical flexibility. There are four main research fronts in the development of 1D SCs: 1) enhancing mechanical characteristics, 2) achieving superior electrochemical performance, 3) enabling multiple device integration, and 4) demonstrating multifunctionality. Here, a brief history of 1D SCs is presented and significant research achievements regarding the four fronts identified as the main pillars of the development of 1D SCs are highlighted. The current challenges of the fabrication and utilization of 1D SCs are critically examined and potential solutions are analyzed. Plus, the performance inconsistencies arising from the improper use and extreme diversity of performance evaluation and reporting methods are highlighted. Beyond, perspectives on future efforts are provided and goals regarding the four research fronts are set, to further push 1D SCs toward practical applications. The development of 1D SCs is summarized here, with existing obstacles diagnosed, corresponding solutions proposed, and future directions indicated accordingly.
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Affiliation(s)
- Shengli Zhai
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - H Enis Karahan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Chaojun Wang
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Zengxia Pei
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Li Wei
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Yuan Chen
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
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Sethunga G, Karahan HE, Wang R, Bae TH. PDMS-coated porous PVDF hollow fiber membranes for efficient recovery of dissolved biomethane from anaerobic effluents. J Memb Sci 2019. [DOI: 10.1016/j.memsci.2019.05.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Ng CK, Karahan HE, Loo SCJ, Chen Y, Cao B. Biofilm-Templated Heteroatom-Doped Carbon-Palladium Nanocomposite Catalyst for Hexavalent Chromium Reduction. ACS Appl Mater Interfaces 2019; 11:24018-24026. [PMID: 31251015 DOI: 10.1021/acsami.9b04095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this study, we report an interdisciplinary and novel strategy toward biofilm engineering for the development of a biofilm-templated heteroatom-doped catalytic system through bioreduction and biofilm matrix-facilitated immobilization of the in situ-formed catalytic nanoparticles followed by controlled pyrolysis. We showed that (i) even under room temperature and bulk aerobic conditions, Shewanella oneidensis MR-1 biofilms reduced Pd(II) to form Pd(0) nanocrystals (∼10 to 20 nm) that were immobilized in the biofilm matrix and in cellular membranes, (ii) the MR-1 biofilms with the immobilized Pd(0) nanocrystals exhibited nanocatalytic activity, (iii) exposure to Pd(II) greatly increased the rate of cell detachment from the biofilm and posed a risk of biofilm dispersal, (iv) controlled pyrolysis (carbonization) of the biofilm led to the formation of a stable heteroatom-doped carbon-palladium (C-Pd) nanocomposite catalyst, and (v) the biofilm-templated C-Pd nanocomposite catalyst exhibited a high Cr(VI) reduction activity and maintained a high reduction rate over multiple catalytic cycles. Considering that bacteria are capable of synthesizing a wide range of metal and metalloid nanoparticles, the biofilm-templated approach for the fabrication of the catalytic C-Pd nanocomposite we have demonstrated here should prove to be widely applicable for the production of different nanocomposites that are of importance to various environmental applications.
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Affiliation(s)
- Chun Kiat Ng
- Singapore Centre for Environmental Life Sciences Engineering, Interdisciplinary Graduate School , Nanyang Technological University , 637551 Singapore
- Department of Engineering Science , University of Oxford , Oxford OX1 3PJ , United Kingdom
| | - H Enis Karahan
- School of Chemical and Biomedical Engineering , Nanyang Technological University , 637459 Singapore
| | - Say Chye Joachim Loo
- Singapore Centre for Environmental Life Sciences Engineering, Interdisciplinary Graduate School , Nanyang Technological University , 637551 Singapore
| | - Yuan Chen
- The University of Sydney, School of Chemical and Biomolecular Engineering , Sydney , New South Wales 2006 , Australia
| | - Bin Cao
- Singapore Centre for Environmental Life Sciences Engineering, Interdisciplinary Graduate School , Nanyang Technological University , 637551 Singapore
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Wang L, Yuan Z, Karahan HE, Wang Y, Sui X, Liu F, Chen Y. Nanocarbon materials in water disinfection: state-of-the-art and future directions. Nanoscale 2019; 11:9819-9839. [PMID: 31080989 DOI: 10.1039/c9nr02007a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Water disinfection practices are critical for supplying safe drinking water. Existing water disinfection methods come with various drawbacks, calling for alternative or complementary solutions. Nanocarbon materials (NCMs) offer unique advantages for water disinfection owing to their high antimicrobial activity, often low environmental/human toxicity, and tunable physicochemical properties. Nevertheless, it is a challenge to assess the research progress made so far due to the structure and property diversity in NCMs as well as their different targeted applications. Because of these, here we provide a broad outline of this emerging field in three parts. First, we introduce the antimicrobial activities of the different types of NCMs, including fullerenes, nanodiamonds, carbon (nano)dots, carbon nanotubes, and graphene-family materials. Next, we discuss the current status in applying these NCMs for different water disinfection problems, especially as hydrogel filters, filtration membranes, recyclable aggregates, and electrochemical devices. We also introduce the use of NCMs in photocatalysts for photocatalytic water disinfection. Lastly, we put forward the key hurdles of the field that hamper the realization of the practical applications and propose possible directions for future investigations to address those. We hope that this minireview will encourage researchers to tackle these challenges and innovate NCM-based water disinfection platforms in the near future.
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Affiliation(s)
- Liang Wang
- Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Ziwen Yuan
- The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia.
| | - H Enis Karahan
- Nanyang Technological University, School of Chemical and Biomedical Engineering, 62 Nanyang Drive, 637459, Singapore
| | - Yilei Wang
- Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | - Xiao Sui
- The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia.
| | - Fei Liu
- The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia. and State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Guangzhou 510070, China
| | - Yuan Chen
- The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia.
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Wang L, He J, Zhu L, Wang Y, Feng X, Chang B, Karahan HE, Chen Y. Assembly of pi-functionalized quaternary ammonium compounds with graphene hydrogel for efficient water disinfection. J Colloid Interface Sci 2019; 535:149-158. [DOI: 10.1016/j.jcis.2018.09.084] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 09/23/2018] [Accepted: 09/24/2018] [Indexed: 10/28/2022]
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Karahan HE, Wang Y, Li W, Liu F, Wang L, Sui X, Riaz MA, Chen Y. Antimicrobial graphene materials: the interplay of complex materials characteristics and competing mechanisms. Biomater Sci 2018; 6:766-773. [PMID: 29387845 DOI: 10.1039/c7bm00987a] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Graphene materials (GMs) exhibit attractive antimicrobial activities promising for biomedical and environmental applications. However, we still lack full control over their behaviour and performance mainly due to the complications arising from the coexistence and interplay of multiple factors. Therefore, in this minireview, we attempt to illustrate the structure-property-activity relationships of GMs' antimicrobial activity. We first examine the chemical/physical complexity of GMs focusing on five aspects of their materials characteristics: (i) chemical composition, (ii) impurities and imperfections, (iii) lateral dimension, (iv) self-association (e.g., restacking), and (v) composite/hybrid formation. Next, we briefly summarise the current understanding of their antimicrobial mechanisms. Then, we assign the outlined materials characteristics of GMs to the proposed antimicrobial mechanisms. Lastly, we share our vision regarding the future of research and development in this fast-emerging field.
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Affiliation(s)
- H Enis Karahan
- The University of Sydney, School of Chemical and Biomolecular Engineering, NSW 2006, Australia.
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Chuah CY, Goh K, Yang Y, Gong H, Li W, Karahan HE, Guiver MD, Wang R, Bae TH. Harnessing Filler Materials for Enhancing Biogas Separation Membranes. Chem Rev 2018; 118:8655-8769. [DOI: 10.1021/acs.chemrev.8b00091] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Chong Yang Chuah
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Kunli Goh
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Singapore Membrane Technology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Yanqin Yang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Singapore Membrane Technology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Heqing Gong
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Wen Li
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - H. Enis Karahan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Singapore Membrane Technology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Michael D. Guiver
- State Key Laboratory of Engines, School of Mechanical Engineering, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Rong Wang
- Singapore Membrane Technology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
- School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 649798, Singapore
| | - Tae-Hyun Bae
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Singapore Membrane Technology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
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Wei L, Karahan HE, Zhai S, Liu H, Chen X, Zhou Z, Lei Y, Liu Z, Chen Y. Amorphous Bimetallic Oxide-Graphene Hybrids as Bifunctional Oxygen Electrocatalysts for Rechargeable Zn-Air Batteries. Adv Mater 2017; 29:1701410. [PMID: 28804931 DOI: 10.1002/adma.201701410] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Revised: 04/28/2017] [Indexed: 05/20/2023]
Abstract
Metal oxides of earth-abundant elements are promising electrocatalysts to overcome the sluggish oxygen evolution and oxygen reduction reaction (OER/ORR) in many electrochemical energy-conversion devices. However, it is difficult to control their catalytic activity precisely. Here, a general three-stage synthesis strategy is described to produce a family of hybrid materials comprising amorphous bimetallic oxide nanoparticles anchored on N-doped reduced graphene oxide with simultaneous control of nanoparticle elemental composition, size, and crystallinity. Amorphous Fe0.5 Co0.5 Ox is obtained from Prussian blue analog nanocrystals, showing excellent OER activity with a Tafel slope of 30.1 mV dec-1 and an overpotential of 257 mV for 10 mA cm-2 and superior ORR activity with a large limiting current density of -5.25 mA cm-2 at 0.6 V. A fabricated Zn-air battery delivers a specific capacity of 756 mA h gZn-1 (corresponding to an energy density of 904 W h kgZn-1 ), a peak power density of 86 mW cm-2 and can be cycled over 120 h at 10 mA cm-2 . Other two amorphous bimetallic, Ni0.4 Fe0.6 Ox and Ni0.33 Co0.67 Ox , are also produced to demonstrate the general applicability of this method for synthesizing binary metal oxides with controllable structures as electrocatalysts for energy conversion.
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Affiliation(s)
- Li Wei
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - H Enis Karahan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| | - Shengli Zhai
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore
| | - Hongwei Liu
- The Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Xuncai Chen
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Zheng Zhou
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Yaojie Lei
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Zongwen Liu
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
| | - Yuan Chen
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, 2006, Australia
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14
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Xu K, Li L, Cui M, Han Y, Karahan HE, Chow VTK, Xu C. Cold Chain-Free Storable Hydrogel for Infant-Friendly Oral Delivery of Amoxicillin for the Treatment of Pneumococcal Pneumonia. ACS Appl Mater Interfaces 2017; 9:18440-18449. [PMID: 28513136 PMCID: PMC5465509 DOI: 10.1021/acsami.7b01462] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
Pneumonia is the major cause of death in children under five, particularly in developing countries. Antibiotics such as amoxicillin greatly help in mitigating this problem. However, there is a lack of an infant/toddler-friendly formulation for countries with limited clean water orr electricity. Here, we report the development of a shear-thinning hydrogel system for the oral delivery of amoxicillin to infant/toddler patients, without the need of clean water and refrigeration. The hydrogel formulation consists of metolose (hydroxypropyl methylcellulose) and amoxicillin. It preserves the structural integrity of antibiotics and their antibacterial activity over 12 weeks at room temperature. Pharmacokinetic profiling of mice reveals that the hydrogel formulation increases the bioavailability of drugs by ∼18% compared to that with aqueous amoxicillin formulation. More importantly, oral gavage of this formulation in a mouse model of secondary pneumococcal pneumonia significantly ameliorates inflammatory infiltration and tissue damage in lungs, with a 10-fold reduction in bacterial counts compared to those in untreated ones. Given the remarkable antibacterial efficacy as well as the use of FDA-regulated ingredients (metolose and amoxicillin), the hydrogel formulation holds great promise for rapid clinical translation.
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Affiliation(s)
- Keming Xu
- School of Chemical
and Biomedical Engineering, Nanyang Technological
University, 70 Nanyang
Drive, 637457 Singapore
| | - Liang Li
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore
| | - Mingyue Cui
- School of Chemical
and Biomedical Engineering, Nanyang Technological
University, 70 Nanyang
Drive, 637457 Singapore
| | - Yiyuan Han
- School of Chemical
and Biomedical Engineering, Nanyang Technological
University, 70 Nanyang
Drive, 637457 Singapore
| | - H. Enis Karahan
- School of Chemical
and Biomedical Engineering, Nanyang Technological
University, 70 Nanyang
Drive, 637457 Singapore
| | - Vincent T. K. Chow
- Department of Microbiology and Immunology,
Yong Loo Lin School of Medicine, National
University of Singapore, 5 Science Drive 2, 117545 Singapore
| | - Chenjie Xu
- School of Chemical
and Biomedical Engineering, Nanyang Technological
University, 70 Nanyang
Drive, 637457 Singapore
- NTU-Northwestern Institute for Nanomedicine, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore
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15
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Wei L, Goh K, Birer Ö, Karahan HE, Chang J, Zhai S, Chen X, Chen Y. A hierarchically porous nickel-copper phosphide nano-foam for efficient electrochemical splitting of water. Nanoscale 2017; 9:4401-4408. [PMID: 28191583 DOI: 10.1039/c6nr09864a] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Electrochemical splitting of water to produce oxygen (O2) and hydrogen (H2) through a cathodic hydrogen evolution reaction (HER) and an anodic oxygen evolution reaction (OER) is a promising green approach for sustainable energy supply. Here we demonstrated a porous nickel-copper phosphide (NiCuP) nano-foam as a bifunctional electrocatalyst for highly efficient total water splitting. Prepared from a bubble-templated electrodeposition method and subsequent low-temperature phosphidization, NiCuP has a hierarchical pore structure with a large electrochemical active surface area. To reach a high current density of 50 mA cm-2, it requires merely 146 and 300 mV with small Tafel slopes of 47 and 49 mV dec-1 for HER and OER, respectively. The total water splitting test using NiCuP as both the anode and cathode showed nearly 100% Faradic efficiency and surpassed the performances of electrode pairs using commercial Pt/C and IrO2 catalysts under our test conditions. The high activity of NiCuP can be attributed to (1) the conductive NiCu substrates, (2) a large electrochemically active surface area together with a combination of pores of different sizes, and (3) the formation of active Ni/Cu oxides/hydroxides while keeping a portion of more conductive Ni/Cu phosphides in the nano-foam. We expect the current catalyst to enable the manufacturing of affordable water splitting systems.
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Affiliation(s)
- Li Wei
- The University of Sydney, School of Chemical and Biomolecular Engineering, Sydney, New South Wales 2006, Australia.
| | - Kunli Goh
- Nanyang Technological University, School of Chemical and Biomedical Engineering, 637459, Singapore
| | - Özgür Birer
- Koç University, Chemistry Department and KUYTAM Surface Science and Technology Center, Rumelifeneri Yolu, Sarıyer, 34450, Istanbul, Turkey
| | - H Enis Karahan
- Nanyang Technological University, School of Chemical and Biomedical Engineering, 637459, Singapore
| | - Jian Chang
- Nanyang Technological University, School of Chemical and Biomedical Engineering, 637459, Singapore
| | - Shengli Zhai
- The University of Sydney, School of Chemical and Biomolecular Engineering, Sydney, New South Wales 2006, Australia. and Nanyang Technological University, School of Chemical and Biomedical Engineering, 637459, Singapore
| | - Xuncai Chen
- The University of Sydney, School of Chemical and Biomolecular Engineering, Sydney, New South Wales 2006, Australia.
| | - Yuan Chen
- The University of Sydney, School of Chemical and Biomolecular Engineering, Sydney, New South Wales 2006, Australia.
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16
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Yuan Y, Karahan HE, Yıldırım C, Wei L, Birer Ö, Zhai S, Lau R, Chen Y. "Smart poisoning" of Co/SiO 2 catalysts by sulfidation for chirality-selective synthesis of (9,8) single-walled carbon nanotubes. Nanoscale 2016; 8:17705-17713. [PMID: 27722714 DOI: 10.1039/c6nr05938d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The chirality-selective synthesis of relatively large (diameter > 1 nm) single-walled carbon nanotubes (SWCNTs) is of great interest for a variety of practical applications, but only a few catalysts are available so far. Previous studies suggested that S (compounds) can enhance the chirality-selectivity of Co catalysts in SWCNT synthesis, however, the mechanism behind is not fully understood, and no tailorable methodology has yet been developed. Here, we demonstrate a facile approach to achieve the chirality-selective synthesis of SWCNTs by the sulfidation-based poisoning of silica-supported Co catalysts using a mixture of H2S and H2. The UV-vis-NIR, photoluminescence, and Raman spectroscopy results together show that the resulting SWCNTs have a narrow diameter distribution of around 1.2 nm, and (9,8) nanotubes have an abundance of ∼38% among the semiconducting species. More importantly, the carbon yield achieved by the sulfided catalyst (2.5 wt%) is similar to that of the nonsulfided one (2.7 wt%). The characterization of the catalysts by X-ray diffraction, X-ray photoelectron spectroscopy, X-ray fluorescence, and H2 temperature-programmed reduction shows that the sulfidation leads to the formation of Co9S8 nanoparticles. However, Co9S8 nanoparticles are reduced back to regenerate metallic Co nanoparticles during the synthesis of SWCNTs, which maintain a high carbon yield. In this process, Co9S8 nanoparticles seemingly intermediate the production of Co nanoparticles with narrow size distribution. Due to the fact that the poisoning step improves the quality of the end-product rather than hampering the growth process, we have coined the process developed as "smart poisoning". This study not only reveals the mechanism behind the beneficial role of S in the selective synthesis of relatively large SWCNTs but also presents a promising method to create chirality-selective catalysts with high activity for scalable synthesis.
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Affiliation(s)
- Yang Yuan
- Nanyang Technological University, School of Chemical and Biomedical Engineering, Singapore, 637459, Singapore
| | - H Enis Karahan
- Nanyang Technological University, School of Chemical and Biomedical Engineering, Singapore, 637459, Singapore and The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia.
| | - Cansu Yıldırım
- Koç University, KUYTAM Surface Science and Technology Center, Rumelifeneri Yolu, Sarıyer, 34450, İstanbul, Turkey
| | - Li Wei
- The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia.
| | - Özgür Birer
- Koç University, KUYTAM Surface Science and Technology Center, Rumelifeneri Yolu, Sarıyer, 34450, İstanbul, Turkey and Koç University, Chemistry Department, Rumelifeneri Yolu, Sarıyer, 34450, İstanbul, Turkey
| | - Shengli Zhai
- Nanyang Technological University, School of Chemical and Biomedical Engineering, Singapore, 637459, Singapore and The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia.
| | - Raymond Lau
- Nanyang Technological University, School of Chemical and Biomedical Engineering, Singapore, 637459, Singapore
| | - Yuan Chen
- The University of Sydney, School of Chemical and Biomolecular Engineering, NSW, 2006, Australia.
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17
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Karahan HE, Wei L, Goh K, Liu Z, Birer Ö, Dehghani F, Xu C, Wei J, Chen Y. Bacterial physiology is a key modulator of the antibacterial activity of graphene oxide. Nanoscale 2016; 8:17181-17189. [PMID: 27722381 DOI: 10.1039/c6nr05745d] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Carbon-based nanomaterials have a great potential as novel antibacterial agents; however, their interactions with bacteria are not fully understood. This study demonstrates that the antibacterial activity of graphene oxide (GO) depends on the physiological state of cells for both Gram-negative and -positive bacteria. GO susceptibility of bacteria is the highest in the exponential growth phase, which are in growing physiology, and stationary-phase (non-growing) cells are quite resistant against GO. Importantly, the order of GO susceptibility of E. coli with respect to the growth phases (exponential ≫ decline > stationary) correlates well with the changes in the envelope ultrastructures of the cells. Our findings are not only fundamentally important but also particularly critical for practical antimicrobial applications of carbon-based nanomaterials.
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Affiliation(s)
- H Enis Karahan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore and Singapore Institute of Manufacturing Technology (SIMTech), Singapore, 638075, Singapore.
| | - Li Wei
- School of Chemical and Biomolecular Engineering, The University of Sydney, NSW 2006, Australia.
| | - Kunli Goh
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Zhe Liu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Özgür Birer
- Chemistry Department, Koç University, Rumelifeneri Yolu, Sarıyer, 34450, Istanbul, Turkey and KUYTAM Surface Science and Technology Center, Koç University, Rumelifeneri Yolu, Sarıyer, 34450, Istanbul, Turkey
| | - Fariba Dehghani
- School of Chemical and Biomolecular Engineering, The University of Sydney, NSW 2006, Australia.
| | - Chenjie Xu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore and NTU-Northwestern Institute of Nanomedicine, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Jun Wei
- Singapore Institute of Manufacturing Technology (SIMTech), Singapore, 638075, Singapore.
| | - Yuan Chen
- School of Chemical and Biomolecular Engineering, The University of Sydney, NSW 2006, Australia.
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18
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Karahan HE, Birer Ö, Karakuş K, Yıldırım C. Shadow-casted ultrathin surface coatings of titanium and titanium/silicon oxide sol particles via ultrasound-assisted deposition. Ultrason Sonochem 2016; 31:481-489. [PMID: 26964975 DOI: 10.1016/j.ultsonch.2016.01.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 12/16/2015] [Accepted: 01/27/2016] [Indexed: 06/05/2023]
Abstract
Ultrasound-assisted deposition (USAD) of sol nanoparticles enables the formation of uniform and inherently stable thin films. However, the technique still suffers in coating hard substrates and the use of fast-reacting sol-gel precursors still remains challenging. Here, we report on the deposition of ultrathin titanium and titanium/silicon hybrid oxide coatings using hydroxylated silicon wafers as a model hard substrate. We use acetic acid as the catalyst which also suppresses the reactivity of titanium tetraisopropoxide while increasing the reactivity of tetraethyl orthosilicate through chemical modifications. Taking the advantage of this peculiar behavior, we successfully prepared titanium and titanium/silicon hybrid oxide coatings by USAD. Varying the amount of acetic acid in the reaction media, we managed to modulate thickness and surface roughness of the coatings in nanoscale. Field-emission scanning electron microscopy and atomic force microscopy studies showed the formation of conformal coatings having nanoroughness. Quantitative chemical state maps obtained by x-ray photoelectron spectroscopy (XPS) suggested the formation of ultrathin (<10nm) coatings and thickness measurements by rotating analyzer ellipsometry supported this observation. For the first time, XPS chemical maps revealed the transport effect of ultrasonic waves since coatings were directly cast on rectangular substrates as circular shadows of the horn with clear thickness gradient from the center to the edges. In addition to the progress made in coating hard substrates, employing fast-reacting precursors and achieving hybrid coatings; this report provides the first visual evidence on previously suggested "acceleration and smashing" mechanism as the main driving force of USAD.
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Affiliation(s)
- H Enis Karahan
- Materials Science and Engineering Graduate Program, Koç University, Sarıyer, Istanbul 34450, Turkey; Chemistry Department, Koç University, Sarıyer, Istanbul 34450, Turkey
| | - Özgür Birer
- Materials Science and Engineering Graduate Program, Koç University, Sarıyer, Istanbul 34450, Turkey; Chemistry Department, Koç University, Sarıyer, Istanbul 34450, Turkey; KUYTAM, Surface Science and Technology Research Center, Koç University, Sarıyer, Istanbul 34450, Turkey.
| | - Kerem Karakuş
- Materials Science and Engineering Graduate Program, Koç University, Sarıyer, Istanbul 34450, Turkey; Chemistry Department, Koç University, Sarıyer, Istanbul 34450, Turkey
| | - Cansu Yıldırım
- KUYTAM, Surface Science and Technology Research Center, Koç University, Sarıyer, Istanbul 34450, Turkey
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19
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Karahan HE, Wei L, Goh K, Wiraja C, Liu Z, Xu C, Jiang R, Wei J, Chen Y. Synergism of Water Shock and a Biocompatible Block Copolymer Potentiates the Antibacterial Activity of Graphene Oxide. Small 2016; 12:951-62. [PMID: 26707949 DOI: 10.1002/smll.201502496] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 11/08/2015] [Indexed: 05/14/2023]
Abstract
Graphene oxide (GO) is promising in the fight against pathogenic bacteria. However, the antibacterial activity of pristine GO is relatively low and concern over human cytotoxicity further limits its potential. This study demonstrates a general approach to address both issues. The developed approach synergistically combines the water shock treatment (i.e., a sudden decrease in environmental salinity) and the use of a biocompatible block copolymer (Pluronic F-127) as a synergist co-agent. Hypoosmotic stress induced by water shock makes gram-negative pathogens more susceptible to GO. Pluronic forms highly stable nanoassemblies with GO (Pluronic-GO) that can populate around bacterial envelopes favoring the interactions between GO and bacteria. The antibacterial activity of GO at a low concentration (50 μg mL(-1) ) increases from <30% to virtually complete killing (>99%) when complemented with water shock and Pluronic (5 mg mL(-1) ) at ≈2-2.5 h of exposure. Results suggest that the enhanced dispersion of GO and the osmotic pressure generated on bacterial envelopes by polymers together potentiate GO. Pluronic also significantly suppresses the toxicity of GO toward human fibroblast cells. Fundamentally, the results highlight the crucial role of physicochemical milieu in the antibacterial activity of GO. The demonstrated strategy has potentials for daily-life bacterial disinfection applications, as hypotonic Pluronic-GO mixture is both safe and effective.
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Affiliation(s)
- H Enis Karahan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
- Singapore Institute of Manufacturing Technology (SIMTech), Singapore, 638075, Singapore
| | - Li Wei
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Kunli Goh
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Christian Wiraja
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Zhe Liu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Chenjie Xu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
- NTU-Northwestern Institute of Nanomedicine, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Rongrong Jiang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
| | - Jun Wei
- Singapore Institute of Manufacturing Technology (SIMTech), Singapore, 638075, Singapore
| | - Yuan Chen
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, 2006, Australia
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Wei L, Yu D, Karahan HE, Birer Ö, Goh K, Yuan Y, Jiang W, Liang W, Chen Y. E. coli-derived carbon with nitrogen and phosphorus dual functionalities for oxygen reduction reaction. Catal Today 2015. [DOI: 10.1016/j.cattod.2014.08.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Karahan HE, Eyüboğlu L, Kıyılar D, Demirel AL. pH-stability and pH-annealing of H-bonded multilayer films prepared by layer-by-layer spin-assembly. Eur Polym J 2014. [DOI: 10.1016/j.eurpolymj.2014.04.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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