1
|
Mubeen B, Ansar AN, Rasool R, Ullah I, Imam SS, Alshehri S, Ghoneim MM, Alzarea SI, Nadeem MS, Kazmi I. Nanotechnology as a Novel Approach in Combating Microbes Providing an Alternative to Antibiotics. Antibiotics (Basel) 2021; 10:1473. [PMID: 34943685 PMCID: PMC8698349 DOI: 10.3390/antibiotics10121473] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/19/2021] [Accepted: 11/25/2021] [Indexed: 12/15/2022] Open
Abstract
The emergence of infectious diseases promises to be one of the leading mortality factors in the healthcare sector. Although several drugs are available on the market, newly found microorganisms carrying multidrug resistance (MDR) against which existing drugs cannot function effectively, giving rise to escalated antibiotic dosage therapies and the need to develop novel drugs, which require time, money, and manpower. Thus, the exploitation of antimicrobials has led to the production of MDR bacteria, and their prevalence and growth are a major concern. Novel approaches to prevent antimicrobial drug resistance are in practice. Nanotechnology-based innovation provides physicians and patients the opportunity to overcome the crisis of drug resistance. Nanoparticles have promising potential in the healthcare sector. Recently, nanoparticles have been designed to address pathogenic microorganisms. A multitude of processes that can vary with various traits, including size, morphology, electrical charge, and surface coatings, allow researchers to develop novel composite antimicrobial substances for use in different applications performing antimicrobial activities. The antimicrobial activity of inorganic and carbon-based nanoparticles can be applied to various research, medical, and industrial uses in the future and offer a solution to the crisis of antimicrobial resistance to traditional approaches. Metal-based nanoparticles have also been extensively studied for many biomedical applications. In addition to reduced size and selectivity for bacteria, metal-based nanoparticles have proven effective against pathogens listed as a priority, according to the World Health Organization (WHO). Moreover, antimicrobial studies of nanoparticles were carried out not only in vitro but in vivo as well in order to investigate their efficacy. In addition, nanomaterials provide numerous opportunities for infection prevention, diagnosis, treatment, and biofilm control. This study emphasizes the antimicrobial effects of nanoparticles and contrasts nanoparticles' with antibiotics' role in the fight against pathogenic microorganisms. Future prospects revolve around developing new strategies and products to prevent, control, and treat microbial infections in humans and other animals, including viral infections seen in the current pandemic scenarios.
Collapse
Affiliation(s)
- Bismillah Mubeen
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore 54000, Pakistan; (B.M.); (A.N.A.); (R.R.); (I.U.)
| | - Aunza Nayab Ansar
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore 54000, Pakistan; (B.M.); (A.N.A.); (R.R.); (I.U.)
| | - Rabia Rasool
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore 54000, Pakistan; (B.M.); (A.N.A.); (R.R.); (I.U.)
| | - Inam Ullah
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore 54000, Pakistan; (B.M.); (A.N.A.); (R.R.); (I.U.)
| | - Syed Sarim Imam
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia; (S.S.I.); (S.A.)
| | - Sultan Alshehri
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia; (S.S.I.); (S.A.)
| | - Mohammed M. Ghoneim
- Department of Pharmacy Practice, College of Pharmacy, AlMaarefa University, Ad Diriyah 13713, Saudi Arabia;
| | - Sami I. Alzarea
- Department of Pharmacology, College of Pharmacy, Jouf University, Sakaka 72341, Saudi Arabia;
| | - Muhammad Shahid Nadeem
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Imran Kazmi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| |
Collapse
|
2
|
Ag-loaded and Pd-loaded ZnO nanofiber membranes: preparation via electrospinning and application in photocatalytic antibacterial and dye degradation. APPLIED NANOSCIENCE 2021. [DOI: 10.1007/s13204-021-02056-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
3
|
Danfá S, Martins RC, Quina MJ, Gomes J. Supported TiO 2 in Ceramic Materials for the Photocatalytic Degradation of Contaminants of Emerging Concern in Liquid Effluents: A Review. Molecules 2021; 26:molecules26175363. [PMID: 34500795 PMCID: PMC8434047 DOI: 10.3390/molecules26175363] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 08/27/2021] [Accepted: 08/31/2021] [Indexed: 12/03/2022] Open
Abstract
The application of TiO2 as a slurry catalyst for the degradation of contaminants of emerging concern (CEC) in liquid effluents has some drawbacks due to the difficulties in the catalyst reutilization. Thus, sophisticated and expensive separation methods are required after the reaction step. Alternatively, several types of materials have been used to support powder catalysts, so that fixed or fluidized bed reactors may be used. In this context, the objective of this work is to systematize and analyze the results of research inherent to the application of ceramic materials as support of TiO2 in the photocatalytic CEC removal from liquid effluents. Firstly, an overview is given about the treatment processes able to degrade CEC. In particular, the photocatalysts supported in ceramic materials are analyzed, namely the immobilization techniques applied to support TiO2 in these materials. Finally, a critical review of the literature dedicated to photocatalysis with supported TiO2 is presented, where the performance of the catalyst is considered as well as the main drivers and barriers for implementing this process. A focal point in the future is to investigate the possibility of depurating effluents and promote water reuse in safe conditions, and the supported TiO2 in ceramic materials may play a role in this scope.
Collapse
|
4
|
He J, Kumar A, Khan M, Lo IMC. Critical review of photocatalytic disinfection of bacteria: from noble metals- and carbon nanomaterials-TiO 2 composites to challenges of water characteristics and strategic solutions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 758:143953. [PMID: 33321366 DOI: 10.1016/j.scitotenv.2020.143953] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/10/2020] [Accepted: 11/13/2020] [Indexed: 06/12/2023]
Abstract
This critical review covers ways to improve TiO2-based photocatalysts, how water characteristics may affect photocatalytic disinfection, and strategies to tackle the challenges arising from water characteristics. Photocatalysis has shown much promise in the disinfection of water/wastewater, because photocatalysis does not produce toxic by-products, and is driven by green solar energy. There are however several drawbacks that are curbing the prevalence of photocatalytic disinfection applications: one, the efficiency of photocatalysts may limit popular utilization; two, the water characteristics may present some challenges to the process. TiO2-based photocatalysts may be readily improved if composited with noble metals or carbon nanomaterials. Noble metals give TiO2-based composites a higher affinity for dissolved oxygen, and induce plasmonic and Schottky effects in the TiO2; carbon nanomaterials with a tunable structure, on the other hand, give the composites an improved charge carrier separation performance. Other than photocatalyst materials, the characteristics of water/wastewater is another crucial factor in the photocatalysis process. Also examined in this review are the crucial impacts that water characteristics have on photocatalysts and their interaction with bacteria. Accordingly, strategies to address the challenge of water characteristics on photocatalytic disinfection are explored: one, to modify the semiconductor conduction band to generate long-lifetime reactive species; two, to improve the interaction between bacteria and photocatalysts.
Collapse
Affiliation(s)
- Juhua He
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Ashutosh Kumar
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Musharib Khan
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Irene M C Lo
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China; Institute for Advanced Study, The Hong Kong University of Science and Technology, Hong Kong, China.
| |
Collapse
|
5
|
Synthesis and Characterization of TiO₂-ZnO-MgO Mixed Oxide and Their Antibacterial Activity. MATERIALS 2019; 12:ma12050698. [PMID: 30818789 PMCID: PMC6427488 DOI: 10.3390/ma12050698] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 02/21/2019] [Accepted: 02/21/2019] [Indexed: 11/16/2022]
Abstract
TiO₂-ZnO-MgO mixed oxide nanomaterials (MONs) were synthetized via the sol-gel method and characterized by scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), nitrogen physisorption analysis, X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), Fourier transform infrared spectroscopy (FTIR), and color (Luminosity (L), a, b, Chrome, hue) parameters. Furthermore, the antimicrobial activity of the MONs was tested against Escherichia coli (EC), Salmonella paratyphi (SP), Staphylococcus aureus (SA), and Listeria monocytogenes (LM). The MONs presented a semi globular-ovoid shape of ≤100 nm. Samples were classified as mesoporous materials and preserved in the TiO₂ anatase phase, with slight changes in the color parameters of the MONs in comparison with pure TiO₂. The MONs exhibited antimicrobial activity, and their effect on the tested bacteria was in the following order: EC > SP > SA > LM. Therefore, MONs could be used as antimicrobial agents for industrial applications.
Collapse
|
6
|
Efficient photocatalytic disinfection of Escherichia coli by N-doped TiO2 coated on coal fly ash cenospheres. J Photochem Photobiol A Chem 2018. [DOI: 10.1016/j.jphotochem.2018.08.045] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
7
|
Graphene oxide nanoribbons as nanomaterial for bone regeneration: Effects on cytotoxicity, gene expression and bactericidal effect. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 78:341-348. [DOI: 10.1016/j.msec.2017.03.278] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 01/28/2017] [Accepted: 03/28/2017] [Indexed: 11/18/2022]
|
8
|
Bui VKH, Park D, Lee YC. Chitosan Combined with ZnO, TiO₂ and Ag Nanoparticles for Antimicrobial Wound Healing Applications: A Mini Review of the Research Trends. Polymers (Basel) 2017; 9:E21. [PMID: 30970696 PMCID: PMC6432267 DOI: 10.3390/polym9010021] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/27/2016] [Accepted: 01/04/2017] [Indexed: 01/19/2023] Open
Abstract
Chitosan is a natural polymer that has been widely utilized for many purposes in the food, textile, agriculture, water treatment, cosmetic and pharmaceutical industries. Based on its characteristics, including biodegradability, non-toxicity and antimicrobial properties, it has been employed effectively in wound healing applications. Importantly, however, it is necessary to improve chitosan's capacities by combination with zinc oxide (ZnO), titanium dioxide (TiO₂) and silver (Ag) nanoparticles (NPs). In this review of many of the latest research papers, we take a closer look at the antibacterial effectiveness of chitosan combined with ZnO, TiO₂ and Ag NPs and also evaluate the specific wound healing application potentials.
Collapse
Affiliation(s)
- Vu Khac Hoang Bui
- Department of BioNano Technology, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si 13120, Gyeonggi-do, Korea.
| | - Duckshin Park
- Korea Railroad Research Institute (KRRI), 176 Cheoldobakmulkwan-ro, Uiwang-si 16105, Gyeonggi-do, Korea.
| | - Young-Chul Lee
- Department of BioNano Technology, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si 13120, Gyeonggi-do, Korea.
| |
Collapse
|
9
|
Lin XH, Miao Y, Li SFY. Location of photocatalytic oxidation processes on anatase titanium dioxide. Catal Sci Technol 2017. [DOI: 10.1039/c6cy02214f] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The detailed mechanism of photocatalytic oxidation processes on the TiO2 surface is still not completely clear, particularly the location of degradation processes.
Collapse
Affiliation(s)
- Xuan Hao Lin
- Department of Chemistry
- National University of Singapore
- 117543 Singapore
| | - Yijia Miao
- Department of Engineering Science
- Oxford University
- UK
| | - Sam Fong Yau Li
- Department of Chemistry
- National University of Singapore
- 117543 Singapore
- NUS Environmental Research Institute (NERI)
- Singapore 117411
| |
Collapse
|
10
|
Abstract
Availability of safe drinking water, a vital natural resource, is still a distant dream to many around the world, especially in developing countries. Increasing human activity and industrialization have led to a wide range of physical, chemical, and biological pollutants entering water bodies and affecting human lives. Efforts to develop efficient, economical, and technologically sound methods to produce clean water for developing countries have increased worldwide. We focus on solar disinfection, filtration, hybrid filtration methods, treatment of harvested rainwater, herbal water disinfection, and arsenic removal technologies. Simple, yet innovative water treatment devices ranging from use of plant xylem as filters, terafilters, and hand pumps to tippy taps designed indigenously are methods mentioned here. By describing the technical aspects of major water disinfection methods relevant for developing countries on medium to small scales and emphasizing their merits, demerits, economics, and scalability, we highlight the current scenario and pave the way for further research and development and scaling up of these processes. This review focuses on clean drinking water, especially for rural populations in developing countries. It describes various water disinfection techniques that are not only economically viable and energy efficient but also employ simple methodologies that are effective in reducing the physical, chemical, and biological pollutants found in drinking water to acceptable limits.
Collapse
Affiliation(s)
- Aniruddha B Pandit
- Department of Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400019, India;
| | | |
Collapse
|
11
|
Barwal A, Chaudhary R. Feasibility study for the treatment of municipal wastewater by using a hybrid bio-solar process. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 177:271-277. [PMID: 27107953 DOI: 10.1016/j.jenvman.2016.04.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 03/30/2016] [Accepted: 04/08/2016] [Indexed: 06/05/2023]
Abstract
A moving bed biofilm reactor (MBBR) coupled with solar parabolic structured system has been designed and developed to get the maximum organic load removal and microbial disinfection from the wastewater. The effluent was first subjected to organic degradation in MBBR (with optimized carrier filling rate of 30%) followed by the bacterial degradation using solar energy in parabolic trough and the changes in values of parameters like pH, turbidity, chemical oxygen demand (COD), bio-chemical oxygen demand (BOD) and microbial count were monitored. The titanium dioxide (TiO2) was used as a photocatalyst for the removal of organic load from the wastewater but in optimized conditions. At optimum dose of 1.0 g/L of TiO2 and pH value of 7.6, maximum COD removal of 69% and 13% was achieved at sunny days (solar irradiation 400-700 W m(-2)) and cloudy days (solar irradiation 170-250 W m(-2)) respectively within 5-6 h solar irradiation time. The results obtained showed that it is possible to decrease in six logarithms (log) the concentration of TC and FC within only 240 min of solar exposure. Moreover, this process can offer economically reasonable, chemical free and practical solution to the processing of municipal wastewater where solar intensity is readily available and can be used for making zero liquid discharge (ZLD) an effective reality.
Collapse
Affiliation(s)
- Anjali Barwal
- School of Energy and Environmental Studies, Faculty of Engineering Sciences, Devi Ahilya University, Takshashila Campus, Khandwa Road, Indore, Madhya Pradesh 452001, India.
| | - Rubina Chaudhary
- School of Energy and Environmental Studies, Faculty of Engineering Sciences, Devi Ahilya University, Takshashila Campus, Khandwa Road, Indore, Madhya Pradesh 452001, India.
| |
Collapse
|
12
|
Bogdan J, Zarzyńska J, Pławińska-Czarnak J. Comparison of Infectious Agents Susceptibility to Photocatalytic Effects of Nanosized Titanium and Zinc Oxides: A Practical Approach. NANOSCALE RESEARCH LETTERS 2015; 10:1023. [PMID: 26239879 PMCID: PMC4523504 DOI: 10.1186/s11671-015-1023-z] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 07/27/2015] [Indexed: 05/20/2023]
Abstract
Nanotechnology contributes towards a more effective eradication of pathogens that have emerged in hospitals, veterinary clinics, and food processing plants and that are resistant to traditional drugs or disinfectants. Since new methods of pathogens eradication must be invented and implemented, nanotechnology seems to have become the response to that acute need. A remarkable achievement in this field of science was the creation of self-disinfecting surfaces that base on advanced oxidation processes (AOPs). Thus, the phenomenon of photocatalysis was practically applied. Among the AOPs that have been most studied in respect of their ability to eradicate viruses, prions, bacteria, yeasts, and molds, there are the processes of TiO2/UV and ZnO/UV. Titanium dioxide (TiO2) and zinc oxide (ZnO) act as photocatalysts, after they have been powdered to nanoparticles. Ultraviolet (UV) radiation is an agent that determines their excitation. Methods using photocatalytic properties of nanosized TiO2 and ZnO prove to be highly efficient in inactivation of infectious agents. Therefore, they are being applied on a growing scale. AOP-based disinfection is regarded as a very promising tool that might help overcome problems in food hygiene and public health protection. The susceptibility of infectious agents to photocatalylic processes can be generally arranged in the following order: viruses > prions > Gram-negative bacteria > Gram-positive bacteria > yeasts > molds.
Collapse
Affiliation(s)
- Janusz Bogdan
- Department of Food Hygiene and Public Health Protection Faculty of Veterinary Medicine, Warsaw University of Life Sciences—SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Joanna Zarzyńska
- Department of Food Hygiene and Public Health Protection Faculty of Veterinary Medicine, Warsaw University of Life Sciences—SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Joanna Pławińska-Czarnak
- Department of Food Hygiene and Public Health Protection Faculty of Veterinary Medicine, Warsaw University of Life Sciences—SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
| |
Collapse
|
13
|
Chueca B, Pagán R, García-Gonzalo D. Differential mechanism of Escherichia coli Inactivation by (+)-limonene as a function of cell physiological state and drug's concentration. PLoS One 2014; 9:e94072. [PMID: 24705541 PMCID: PMC3976388 DOI: 10.1371/journal.pone.0094072] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 03/10/2014] [Indexed: 11/18/2022] Open
Abstract
(+)-limonene is a lipophilic antimicrobial compound, extracted from citrus fruits' essential oils, that is used as a flavouring agent and organic solvent by the food industry. A recent study has proposed a common and controversial mechanism of cell death for bactericidal antibiotics, in which hydroxyl radicals ultimately inactivated cells. Our objective was to determine whether the mechanism of Escherichia coli MG1655 inactivation by (+)-limonene follows that of bactericidal antibiotics. A treatment with 2,000 μL/L (+)-limonene inactivated 4 log10 cycles of exponentially growing E. coli cells in 3 hours. On one hand, an increase of cell survival in the ΔacnB mutant (deficient in a TCA cycle enzyme), or in the presence of 2,2′-dipyridyl (inhibitor of Fenton reaction by iron chelation), thiourea, or cysteamine (hydroxyl radical scavengers) was observed. Moreover, the ΔrecA mutant (deficient in an enzyme involved in SOS response to DNA damage) was more sensitive to (+)-limonene. Thus, this indirect evidence indicates that the mechanism of exponentially growing E. coli cells inactivation by 2,000 μL/L (+)-limonene is due to the TCA cycle and Fenton-mediated hydroxyl radical formation that caused oxidative DNA damage, as observed for bactericidal drugs. However, several differences have been observed between the proposed mechanism for bactericidal drugs and for (+)-limonene. In this regard, our results demonstrated that E. coli inactivation was influenced by its physiological state and the drug's concentration: experiments with stationary-phase cells or 4,000 μL/L (+)-limonene uncovered a different mechanism of cell death, likely unrelated to hydroxyl radicals. Our research has also shown that drug's concentration is an important factor influencing the mechanism of bacterial inactivation by antibiotics, such as kanamycin. These results might help in improving and spreading the use of (+)-limonene as an antimicrobial compound, and in clarifying the controversy about the mechanism of inactivation by bactericidal antibiotics.
Collapse
Affiliation(s)
- Beatriz Chueca
- Tecnología de los Alimentos, Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | - Rafael Pagán
- Tecnología de los Alimentos, Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | - Diego García-Gonzalo
- Tecnología de los Alimentos, Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
- * E-mail:
| |
Collapse
|
14
|
Kochkodan V, Johnson DJ, Hilal N. Polymeric membranes: surface modification for minimizing (bio)colloidal fouling. Adv Colloid Interface Sci 2014; 206:116-40. [PMID: 23777923 DOI: 10.1016/j.cis.2013.05.005] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 05/22/2013] [Accepted: 05/22/2013] [Indexed: 11/16/2022]
Abstract
This paper presents an overview on recent developments in surface modification of polymer membranes for reduction of their fouling with biocolloids and organic colloids in pressure driven membrane processes. First, colloidal interactions such as London-van der Waals, electrical, hydration, hydrophobic, steric forces and membrane surface properties such as hydrophilicity, charge and surface roughness, which affect membrane fouling, have been discussed and the main goals of the membrane surface modification for fouling reduction have been outlined. Thereafter the recent studies on reduction of (bio)colloidal of polymer membranes using ultraviolet/redox initiated surface grafting, physical coating/adsorption of a protective layer on the membrane surface, chemical reactions or surface modification of polymer membranes with nanoparticles as well as using of advanced atomic force microscopy to characterize (bio)colloidal fouling have been critically summarized.
Collapse
Affiliation(s)
- Victor Kochkodan
- Centre for Water Advanced Technologies and Environmental Research (CWATER), College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - Daniel J Johnson
- Centre for Water Advanced Technologies and Environmental Research (CWATER), College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP, UK
| | - Nidal Hilal
- Centre for Water Advanced Technologies and Environmental Research (CWATER), College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP, UK; Masdar Institute of Science and Technology, Abu Dhabi, United Arab Emirates.
| |
Collapse
|
15
|
Zou XY, Xu B, Yu CP, Zhang HW. Imbalance between oxidative and antioxidative systems: toward an understanding of visible light-induced titanium dioxide nanoparticles toxicity. CHEMOSPHERE 2013; 93:2451-2457. [PMID: 24080005 DOI: 10.1016/j.chemosphere.2013.08.076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 07/09/2013] [Accepted: 08/30/2013] [Indexed: 06/02/2023]
Abstract
The broad application of titanium dioxide nanoparticles (TiO(2) NPs) has resulted in the release of substantial quantities of untreated TiO(2) NPs into aquatic systems, which serve as the terminal sink for nanomaterials. These TiO(2) NPs may induce some unexpected toxic effects to aquatic systems. The objectives of this research were to evaluate toxic effects of low dosage TiO(2) NPs on Tetrahymena pyriformis under visible-light illumination conditions and further discuss possible mechanisms. The results showed that TiO(2) NPs accumulated as aggregates in cytosolic vesicles of T. pyriformis. Cell numbers and viability of TiO(2) NPs-exposed groups decreased to (20.2 ± 1.8)% and (17.3 ± 1.9)% after 24h continuous 12000 Lx illumination. Compared with the dark control, the intracellular reactive oxygen species (ROS) levels increased (1.9-fold) by the combination of 5 mg L(-1) TiO(2) NPs and 12000 Lx illumination. Even incubation in the dark for 6h after 12h illumination, superoxide dismutase (SOD) activity of TiO(2) NPs exposed groups still maintained at the high level (about 3.9-fold of dark control). Meanwhile, illumination-induced TiO(2) NPs led to a reduction of scavenging hydroxyl radicals (OH) activity with an average of (14.3 ± 6.5)%. Under illumination conditions, overproduction of reactive oxygen species (ROS) by TiO(2) NPs exceeded the scavenging capability of T. pyriformis and then led to the breakdown of oxidative/anti-oxidative systems, further resulting in cell growth delay and mitochondria dysfunction. All the results revealed that via visible light excitation, oxidative injury may be responsible for the toxic effects of TiO(2) NPs on T. pyriformis.
Collapse
Affiliation(s)
- Xiao-Yan Zou
- Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
| | | | | | | |
Collapse
|
16
|
Gao P, Liu J, Sun DD, Ng W. Graphene oxide-CdS composite with high photocatalytic degradation and disinfection activities under visible light irradiation. JOURNAL OF HAZARDOUS MATERIALS 2013; 250-251:412-20. [PMID: 23500421 DOI: 10.1016/j.jhazmat.2013.02.003] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Revised: 01/18/2013] [Accepted: 02/01/2013] [Indexed: 05/07/2023]
Abstract
Graphene oxide (GO)-CdS composites were synthesized via a novel two-phase mixing method successfully. CdS nanoparticles were uniformly self-assembled on GO sheets at water/toluene interface. The photocatalytic degradation (photodegradation) and disinfection activities of GO-CdS composites were investigated thoroughly. The results show that GO-CdS composites exhibit higher efficiency in photodegradation of various water pollutants than pure CdS nanoparticles under visible light irradiation. In addition, the interactions between GO sheets and CdS nanoparticles inhibit the photo-corrosion of CdS and leaching of Cd(2+). Only 3.5 wt% Cd(2+) of GO-CdS was leached out after photodegradation, while 38.6 wt% Cd(2+) of CdS was lost into aqueous solution. Furthermore, the disinfection activity of GO-CdS composites was investigated for the first time. Nearly 100% of both Gram-negative Escherichia coli (E. coli) and Gram-positive Bacillus subtilis (B. subtilis) were killed within 25 min under visible light irradiation. The excellent performances of GO-CdS composites can be attributed to that (1) effective charge transfer from CdS to GO reduces the recombination rate of photo-generated electron-hole pairs; (2) uniform deposition of CdS on GO sheets eliminates aggregation of CdS nanoparticles; and (3) the strong interactions between GO and CdS enhancing the durability of GO-CdS composites. Finally, the mechanism behind these excellent performances was verified by transient photocurrent measurement and further confirmed by ESR technique as well as employing a radical scavenging species - dimethyl sulfoxide (DMSO).
Collapse
Affiliation(s)
- Peng Gao
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | | | | | | |
Collapse
|
17
|
Zhang T, Yan X, Sun DD. Hierarchically multifunctional K-OMS-2/TiO2/Fe3O4 heterojunctions for the photocatalytic oxidation of humic acid under solar light irradiation. JOURNAL OF HAZARDOUS MATERIALS 2012; 243:302-310. [PMID: 23140876 DOI: 10.1016/j.jhazmat.2012.10.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 10/15/2012] [Accepted: 10/18/2012] [Indexed: 06/01/2023]
Abstract
A multifunctional heterojunctioned K-OMS-2/TiO(2)/Fe(3)O(4) (KTF) nanocomposite was successfully synthesized using a combination of hydrothermal and co-precipitation techniques. The resultant sample was characterized by XRD, FESEM, TEM, N(2) adsorption, XPS and VSM. Its photocatalytic activity was demonstrated in the photocatalytic degradation of humic acid (HA). Morphology characterization showed the hierarchical structure of the synthesized material, and XRD results revealed that both the rutile and anatase TiO(2) structures are present in the sample. The average pore diameters and BET surface area of the synthesized KTF heterojunctions were 40 nm and 134.42 m(2)/g, respectively. XPS spectra confirmed the presence of Fe(3)O(4) and TiO(2) in the synthesized material, and the valences of Mn were kept at +3 and +4 after the grafting of Fe(3)O(4) and TiO(2). The synthesized material showed good magnetic response and photocatalytic activity under simulated solar light irradiation, and 85.7% of HA was decomposed after 120 min in the presence of KTF nanocomposites. The reusability study suggested that the magnetic recovered material was stable enough for multiple recycling usages, verifying its potential application in water purification.
Collapse
Affiliation(s)
- Tong Zhang
- School of Civil and Environmental Engineering, Nanyang Technological University, Nanyang Avenue, 639798 Singapore, Singapore
| | | | | |
Collapse
|
18
|
Hessler CM, Wu MY, Xue Z, Choi H, Seo Y. The influence of capsular extracellular polymeric substances on the interaction between TiO₂ nanoparticles and planktonic bacteria. WATER RESEARCH 2012; 46:4687-4696. [PMID: 22789757 DOI: 10.1016/j.watres.2012.06.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 05/22/2012] [Accepted: 06/06/2012] [Indexed: 06/01/2023]
Abstract
The role of capsular extracellular polymeric substances (EPS) at the surface of planktonic microorganisms was investigated for possible toxicity mitigation from titanium dioxide (TiO₂) nanoparticles, using variable EPS producing wild-type and isogenic mutant strains of Pseudomonas aeruginosa. Membrane integrity assays revealed that increased capsular EPS reduced cell membrane damage. Acting as a barrier to the cell membrane, capsular EPS permitted attachment of nanoparticles to the cell, while simultaneously delaying cellular damage caused by the production of reactive oxygen species (ROS). Modulations in ROS production were monitored in situ; while changes in the chemical composition of the microorganisms before and after exposure were examined with Fourier transform infrared spectroscopy (FTIR). The addition of methanol, a known radical scavenger, was shown to vastly reduce ROS production and membrane integrity losses, while not affecting physical interactions of nanoparticles with the microorganism. The results support that EPS provides an attachment site for nanoparticles, but more importantly act as a barrier to cell membrane oxidation from ROS. These observations provide better understanding of the overall importance of ROS in TiO₂ microbial toxicity.
Collapse
Affiliation(s)
- Christopher M Hessler
- Department of Chemical and Environmental Engineering, University of Toledo, 2801 W. Bancroft St., 3048 Nitschke Hall, Toledo, OH 43606, USA
| | | | | | | | | |
Collapse
|
19
|
Vargas-Reus MA, Memarzadeh K, Huang J, Ren GG, Allaker RP. Antimicrobial activity of nanoparticulate metal oxides against peri-implantitis pathogens. Int J Antimicrob Agents 2012; 40:135-9. [PMID: 22727529 DOI: 10.1016/j.ijantimicag.2012.04.012] [Citation(s) in RCA: 126] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 04/13/2012] [Indexed: 11/25/2022]
Abstract
Dental plaque accumulation may result in peri-implantitis, an inflammatory process causing loss of supporting bone that may lead to dental implant failure. The antimicrobial activities of six metal and metal oxide nanoparticles and two of their composites against bacterial pathogens associated with peri-implantitis were examined under anaerobic conditions. The activities of nanoparticles of silver (Ag), cuprous oxide (Cu(2)O), cupric oxide (CuO), zinc oxide (ZnO), titanium dioxide (TiO(2)), tungsten oxide (WO(3)), Ag+CuO composite and Ag+ZnO composite were assessed by minimum inhibitory (bacteriostatic) concentration (MIC) and minimum bactericidal concentration (MBC) determination against Prevotella intermedia, Porphyromonas gingivalis, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans. Time-kill assays were carried out to examine the dynamics of the antimicrobial activity with ZnO nanoparticles. MIC and MBC values were in the range of <100 μg/mL to 2500 μg/mL and <100 μg/mL to >2500 μg/mL, respectively. The activity of the nanoparticles tested in descending order was Ag>Ag+CuO>Cu(2)O>CuO>Ag+ZnO>ZnO>TiO(2)>WO(3). Time-kill assays with ZnO demonstrated a significant decrease in growth of all species tested within 4h, reaching 100% within 2h for P. gingivalis and within 3h for F. nucleatum and P. intermedia. Coating titanium surfaces of dental and orthopaedic implants with antimicrobial nanoparticles should lead to an increased rate of implant success.
Collapse
Affiliation(s)
- Miguel A Vargas-Reus
- Queen Mary University of London, Barts & The London School of Medicine and Dentistry, Institute of Dentistry, 4 Newark Street, London E1 2AT, UK
| | | | | | | | | |
Collapse
|
20
|
Toxic effects of titanium dioxide nanoparticles on microbial activity and metabolic flux. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-010-0251-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
21
|
Liu L, Liu Z, Bai H, Sun DD. Concurrent filtration and solar photocatalytic disinfection/degradation using high-performance Ag/TiO2 nanofiber membrane. WATER RESEARCH 2012; 46:1101-1112. [PMID: 22196951 DOI: 10.1016/j.watres.2011.12.009] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 11/10/2011] [Accepted: 12/03/2011] [Indexed: 05/28/2023]
Abstract
A facile polyol synthesis was used for the deposition of Ag nanoparticles on electrospun TiO2 nanofibers for the subsequent fabrication of Ag/TiO2 nanofiber membrane. The permeate flux of the Ag/TiO2 nanofiber membrane was remarkably high compared to commercial P25 deposited membrane. The Ag/TiO2 nanofiber membrane achieved 99.9% bacteria inactivation and 80.0% dye degradation under solar irradiation within 30 min. The Ag/TiO2 nanofiber membrane also showed excellent antibacterial capability without solar irradiation. Considering the excellent intrinsic antibacterial activity and high-performance photocatalytic disinfection/degradation under solar irradiation, this novel membrane proved to have promising applications in water purification industry.
Collapse
Affiliation(s)
- Lei Liu
- School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | | | | | | |
Collapse
|
22
|
The inactivation of phages MS2, ΦX174 and PR772 using UV and solar photocatalysis. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2012; 107:1-8. [DOI: 10.1016/j.jphotobiol.2011.10.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 10/19/2011] [Accepted: 10/27/2011] [Indexed: 11/19/2022]
|
23
|
Gong AS, Lanzl CA, Cwiertny DM, Walker SL. Lack of influence of extracellular polymeric substances (EPS) level on hydroxyl radical mediated disinfection of Escherichia coli. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:241-249. [PMID: 22082030 DOI: 10.1021/es202541r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Photolysis of nitrate, a prevalent constituent in agriculturally impacted waters, may influence pathogen attenuation in such systems through production of hydroxyl radical ((•)OH). This study focuses on the efficacy of (•)OH generated during nitrate photolysis in promoting E. coli die-off as a function of extracellular polymeric substances (EPS) coverage. EPS levels of four E. coli isolates were systematically altered through a sonication extraction method and photochemical batch experiments with a solar simulator examined isolate viability loss as a function of time in nitrate solutions. E. coli viability loss over time exhibited two regimes: an initial induction time, t(s), with little decay was followed by rapid exponential decay characterized by a first-order disinfection rate constant, k. Increasing steady-state (•)OH concentrations enhanced E. coli viability loss, increasing values of k and decreasing t(s) values, both of which were quantified with a multitarget bacterial disinfection model. Notably, at a given steady-state (•)OH concentration, values of t(s) and k were independent of EPS levels, nor did they vary among the different E. coli strains considered. Results herein show that while (•)OH generated via nitrate photolysis enhances rates of disinfection in surface water, the mechanism by which (•)OH kills E. coli is relatively insensitive to common bacterial variables.
Collapse
Affiliation(s)
- Amy S Gong
- Department of Chemical & Environmental Engineering, University of California, Riverside, California 92521, United States
| | | | | | | |
Collapse
|
24
|
Titanium Oxide Antibacterial Surfaces in Biomedical Devices. Int J Artif Organs 2011; 34:929-46. [DOI: 10.5301/ijao.5000050] [Citation(s) in RCA: 184] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2011] [Indexed: 02/07/2023]
Abstract
Titanium oxide is a heterogeneous catalyst whose efficient photoinduced activity, related to some of its allotropic forms, paved the way for its widespread technological use. Here, we offer a comparative analysis of the use of titanium oxide as coating for materials in biomedical devices. First, we introduce the photoinduced catalytic mechanisms of TiO2 and their action on biological environment and bacteria. Second, we overview the main physical and chemical technologies for structuring suitable TiO2 coatings on biomedical devices. We then present the approaches for in vitro characterization of these surfaces. Finally, we discuss the main aspects of TiO2 photoactivated antimicrobial activity on medical devices and limitations for these types of applications.
Collapse
|
25
|
Řehoř I, Vilímová V, Jendelová P, Kubíček V, Jirák D, Herynek V, Kapcalová M, Kotek J, Černý J, Hermann P, Lukeš I. Phosphonate–Titanium Dioxide Assemblies: Platform for Multimodal Diagnostic–Therapeutic Nanoprobes. J Med Chem 2011; 54:5185-94. [DOI: 10.1021/jm200449y] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
26
|
Additional effects of silver nanoparticles on bactericidal efficiency depend on calcination temperature and dip-coating speed. Appl Environ Microbiol 2011; 77:5629-34. [PMID: 21724887 DOI: 10.1128/aem.00049-11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There is an increasing interest in the application of photocatalytic properties for disinfection of surfaces, air, and water. Titanium dioxide is widely used as a photocatalyst, and the addition of silver reportedly enhances its bactericidal action. However, the synergy of silver nanoparticles and TiO(2) is not well understood. The photocatalytic elimination of Bacillus atrophaeus was examined under different calcination temperatures, dip-coating speeds, and ratios of TiO(2), SiO(2), and Ag to identify optimal production conditions for the production of TiO(2)- and/or TiO(2)/Ag-coated glass for surface disinfection. Photocatalytic disinfection of pure TiO(2) or TiO(2) plus Ag nanoparticles was dependent primarily on the calcination temperature. The antibacterial activity of TiO(2) films was optimal with a high dip-coating speed and high calcination temperature (600°C). Maximal bacterial inactivation using TiO(2)/Ag-coated glass was also observed following high-speed dip coating but with a low calcination temperature (250°C). Scanning electron microscopy (SEM) showed that the Ag nanoparticles combined together at a high calcination temperature, leading to decreased antibacterial activity of TiO(2)/Ag films due to a smaller surface area of Ag nanoparticles. The presence of Ag enhanced the photocatalytic inactivation rate of TiO(2), producing a more pronounced effect with increasing levels of catalyst loading.
Collapse
|
27
|
Foster HA, Ditta IB, Varghese S, Steele A. Photocatalytic disinfection using titanium dioxide: spectrum and mechanism of antimicrobial activity. Appl Microbiol Biotechnol 2011; 90:1847-68. [PMID: 21523480 PMCID: PMC7079867 DOI: 10.1007/s00253-011-3213-7] [Citation(s) in RCA: 484] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Accepted: 02/12/2011] [Indexed: 11/30/2022]
Abstract
The photocatalytic properties of titanium dioxide are well known and have many applications including the removal of organic contaminants and production of self-cleaning glass. There is an increasing interest in the application of the photocatalytic properties of TiO(2) for disinfection of surfaces, air and water. Reviews of the applications of photocatalysis in disinfection (Gamage and Zhang 2010; Chong et al., Wat Res 44(10):2997-3027, 2010) and of modelling of TiO(2) action have recently been published (Dalrymple et al. , Appl Catal B 98(1-2):27-38, 2010). In this review, we give an overview of the effects of photoactivated TiO(2) on microorganisms. The activity has been shown to be capable of killing a wide range of Gram-negative and Gram-positive bacteria, filamentous and unicellular fungi, algae, protozoa, mammalian viruses and bacteriophage. Resting stages, particularly bacterial endospores, fungal spores and protozoan cysts, are generally more resistant than the vegetative forms, possibly due to the increased cell wall thickness. The killing mechanism involves degradation of the cell wall and cytoplasmic membrane due to the production of reactive oxygen species such as hydroxyl radicals and hydrogen peroxide. This initially leads to leakage of cellular contents then cell lysis and may be followed by complete mineralisation of the organism. Killing is most efficient when there is close contact between the organisms and the TiO(2) catalyst. The killing activity is enhanced by the presence of other antimicrobial agents such as Cu and Ag.
Collapse
Affiliation(s)
- Howard A Foster
- Centre for Parasitology and Disease Research, School of Environment and Life Sciences, University of Salford, The Crescent, Salford, Greater Manchester, UK.
| | | | | | | |
Collapse
|
28
|
Řehoř I, Kubíček V, Kotek J, Hermann P, Száková J, Lukeš I. Modification of Nanocrystalline TiO2 with Phosphonate- and Bis(phosphonate)-Bearing Macrocyclic Complexes: Sorption and Stability Studies. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201001100] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
29
|
Wu P, Xie R, Imlay K, Shang JK. Monolithic Ceramic Foams for Ultrafast Photocatalytic Inactivation of Bacteria. JOURNAL OF THE AMERICAN CERAMIC SOCIETY. AMERICAN CERAMIC SOCIETY 2009; 92:1648-1654. [PMID: 21423830 PMCID: PMC3058526 DOI: 10.1111/j.1551-2916.2009.03069.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Palladium-modified nitrogen-doped titanium dioxide (TiON/PdO) foams were synthesized by a sol-gel process on a polyurethane foam template. The TiON/PdO foam was tested for microbial killing using Escherichia coli cells as a target. Under visible-light illumination, the TiON/PdO foam displayed a strong antimicrobial effect on the bacteria cells in water. The antimicrobial effect was found to be dependent on the palladium content and the calcination temperature. In a flow-through dynamic photoreactor, the new photocatalyst efficiently inactivated E. coli within a short contact time (< 1 min), the shortest ever reported for photocatalytic killing of bacteria. The strong antimicrobial functions of the TiON/PdO foam were related to the charge trapping by PdO and to the high contact efficiency of the foam structure.
Collapse
Affiliation(s)
- Pinggui Wu
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Rongcai Xie
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Kari Imlay
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jian Ku Shang
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Author to whom correspondence should be addressed.
| |
Collapse
|
30
|
Wu P, Xie R, Imlay JA, Shang JK. Visible-Light-Induced Photocatalytic Inactivation of Bacteria by Composite Photocatalysts of Palladium Oxide and Nitrogen-Doped Titanium Oxide. APPLIED CATALYSIS. B, ENVIRONMENTAL 2009; 88:576-581. [PMID: 21423793 PMCID: PMC3059320 DOI: 10.1016/j.apcatb.2008.12.019] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Composite photocatalysts of palladium oxide and nitrogen-doped titanium oxide (PdO/TiON) were synthesized by a solgel process, as convenient forms of nanopowder or immobilized powder on nanofiber. The PdO/TiON catalysts were tested for visible-light-activated photocatalysis using different bacterial indicators, including gram-negative cells of Escherichia coli and Pseudomonas aeruginosa, and gram-positive cells of Staphylococcus aureus. Disinfection data indicated that PdO/TiON composite photocatalysts have a much better photocatalytic activity than either palladium-doped (PdO/TiO(2)) or nitrogen-doped titanium oxide (TiON) under visible-light illumination. The roles of Pd and N were discussed in terms of the production and separation of the charge carriers under visible light illumination. The photocatalytic activity was thus dependent on dopants and light intensity. Microscopic characterization demonstrated that visible-light photocatalysis on PdO/TiON caused drastic damage on the bacteria cell wall and the cell membrane.
Collapse
Affiliation(s)
- Pinggui Wu
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Rongcai Xie
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - James A. Imlay
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jian Ku Shang
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| |
Collapse
|
31
|
Davies CM, Roser DJ, Feitz AJ, Ashbolt NJ. Solar radiation disinfection of drinking water at temperate latitudes: inactivation rates for an optimised reactor configuration. WATER RESEARCH 2009; 43:643-652. [PMID: 19041999 DOI: 10.1016/j.watres.2008.11.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Revised: 11/10/2008] [Accepted: 11/12/2008] [Indexed: 05/27/2023]
Abstract
Solar radiation-driven inactivation of bacteria, virus and protozoan pathogen models was quantified in simulated drinking water at a temperate latitude (34 degrees S). The water was seeded with Enterococcus faecalis, Clostridium sporogenes spores, and P22 bacteriophage, each at ca 1x10(5) mL(-1), and exposed to natural sunlight in 30-L reaction vessels. Water temperature ranged from 17 to 39 degrees C during the experiments lasting up to 6h. Dark controls showed little inactivation and so it was concluded that the inactivation observed was primarily driven by non-thermal processes. The optimised reactor design achieved S90 values (cumulative exposure required for 90% reduction) for the test microorganisms in the range 0.63-1.82 MJ m(-2) of Global Solar Exposure (GSX) without the need for TiO2 as a catalyst. High turbidity (840-920 NTU) only reduced the S(90) value by <40%. Further, when all S90 means were compared this decrease was not statistically significant (prob.>0.05). However, inactivation was significantly reduced for E. faecalis and P22 when the transmittance of UV wavelengths was attenuated by water with high colour (140 PtCo units) or a suboptimally transparent reactor lid (prob.<0.05). S90 values were consistent with those measured by other researchers (ca 1-10 MJ m(-2)) for a range of waters and microorganisms. Although temperatures required for SODIS type pasteurization were not produced, non-thermal inactivation alone appeared to offer a viable means for reliably disinfecting low colour source waters by greater than 4 orders of magnitude on sunny days at 34 degrees S latitude.
Collapse
Affiliation(s)
- C M Davies
- Centre for Water and Waste Technology, Department of Civil and Environmental Engineering, University of New South Wales, Kensington, NSW 2052, Australia.
| | | | | | | |
Collapse
|
32
|
Manjón F, Villén L, García-Fresnadillo D, Orellana G. On the factors influencing the performance of solar reactors for water disinfection with photosensitized singlet oxygen. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:301-307. [PMID: 18350912 DOI: 10.1021/es071762y] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Two solar reactors based on compound parabolic collectors (CPCs) were optimized for water disinfection by photosensitized singlet oxygen (1O2) production in the heterogeneous phase. Sensitizing materials containing Ru(II) complexes immobilized on porous silicone were produced, photochemically characterized, and successfully tested for the inactivation of up to 10(4) CFU mL(-1) of waterborne Escherichia coli (gram-negative) or Enterococcus faecalis (gram-positive) bacteria. The main factors determining the performance of the solar reactors are the type of photosensitizing material, the sensitizer loading, the CPC collector geometry (fin- vs coaxial-type), the fluid rheology, and the balance between concurrent photothermal--photolytic and 1O2 effects on the microorganisms' inactivation. In this way, at the 40 degrees N latitude of Spain, water can be disinfected on a sunny day (0.6-0.8 MJ m(-2) L(-1) accumulated solar radiation dose in the 360-700 nm range, typically 5-6 h of sunlight) with a fin-type reactor containing 0.6 m2 of photosensitizing material saturated with tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) (ca. 2.0 g m(-2)). The optimum rheological conditions require laminar-to-transitional water flow in both prototypes. The fin-type system showed better inactivation efficiency than the coaxial reactor due to a more important photolytic contribution. The durability of the sensitizing materials was tested and the operational lifetime of the photocatalyst is at least three months without any reduction in the bacteria inactivation efficiency. Solar water disinfection with 1O2-generating films is demonstrated to be an effective technique for use in isolated regions of developing countries with high yearly average sunshine.
Collapse
Affiliation(s)
- Francisco Manjón
- Laboratory of Applied Photochemistry, Department of Organic Chemistry, Faculty of Chemistry, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | | | | | | |
Collapse
|
33
|
Méndez-Hermida F, Ares-Mazás E, McGuigan KG, Boyle M, Sichel C, Fernández-Ibáñez P. Disinfection of drinking water contaminated with Cryptosporidium parvum oocysts under natural sunlight and using the photocatalyst TiO2. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2007; 88:105-11. [PMID: 17624798 DOI: 10.1016/j.jphotobiol.2007.05.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 05/14/2007] [Accepted: 05/15/2007] [Indexed: 11/30/2022]
Abstract
The results of a batch-process solar disinfection (SODIS) and solar photocatalytic disinfection (SPCDIS) on drinking water contaminated with Cryptosporidium are reported. Cryptosporidium parvum oocyst suspensions were exposed to natural sunlight in Southern Spain and the oocyst viability was evaluated using two vital dyes [4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI)]. SODIS exposures (strong sunlight) of 8 and 12h reduced oocyst viability from 98% (+/-1.3%) to 11.7% (+/-0.9%) and 0.3% (+/-0.33%), respectively. SODIS reactors fitted with flexible plastic inserts coated with TiO2 powder (SPCDIS) were found to be more effective than those which were not. After 8 and 16 h of overcast and cloudy solar irradiance conditions, SPCDIS reduced oocyst viability from 98.3% (+/-0.3%) to 37.7% (+/-2.6%) and 11.7% (+/-0.7%), respectively, versus to that achieved using SODIS of 81.3% (+/-1.6%) and 36.0% (+/-1.0%), respectively. These results confirm that solar disinfection of drinking water can be an effective household intervention against Cryptosporidium contamination.
Collapse
Affiliation(s)
- Fernando Méndez-Hermida
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Santiago de Compostela, Santiago de Compostela, Spain
| | | | | | | | | | | |
Collapse
|
34
|
Tsarenko SA, Kochkodan VM, Potapchenko NG, Kosinova VN, Goncharuk VV. Use of titanium dioxide for surface modification of polymeric membranes to diminish their biological contamination. RUSS J APPL CHEM+ 2007. [DOI: 10.1134/s1070427207040131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
35
|
Cheng YW, Chan RCY, Wong PK. Disinfection of Legionella pneumophila by photocatalytic oxidation. WATER RESEARCH 2007; 41:842-52. [PMID: 17224169 DOI: 10.1016/j.watres.2006.11.033] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2006] [Revised: 11/18/2006] [Accepted: 11/21/2006] [Indexed: 05/13/2023]
Abstract
Photocatalytic oxidation (PCO) was proven to be efficacious in the inactivation of Legionella pneumophila serogroup 1 Strains 977, 1009, 1014 and ATCC 33153. The local (Strains 997, 1009 and 1014) and ATCC (Strain 33153) strains showed sensitivity differences towards PCO. The inactivation mechanisms of PCO were investigated by transmission and scanning electron microscopy by which PCO was found to disintegrate the cells eventually. Before the disintegration, there was lipid peroxidation of outer and cytoplasmic membrane causing holes formation and leading to the entry of OH into the cells to oxidize the intracellular components. Fatty acid profile analysis found that the amount of saturated, 16-carbon branched-chain fatty acid, which is predominant in Legionella, decreased in the surviving populations from PCO. A relationship between the amount of this fatty acid and the PCO sensitivity of the tested strains was also observed. Mineralization of cells by PCO was proven by total organic carbon analysis.
Collapse
Affiliation(s)
- Y W Cheng
- Department of Biology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | | | | |
Collapse
|
36
|
Dadjour MF, Ogino C, Matsumura S, Nakamura S, Shimizu N. Disinfection of Legionella pneumophila by ultrasonic treatment with TiO2. WATER RESEARCH 2006; 40:1137-42. [PMID: 16515803 DOI: 10.1016/j.watres.2005.12.047] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Revised: 12/26/2005] [Accepted: 12/28/2005] [Indexed: 05/06/2023]
Abstract
An ultrasonic treatment system, using a TiO2 photocatalyst, was used to disinfect Legionella pneumophila. A kinetic study of the process indicates that TiO2 significantly improves the disinfection process. The concentrations of viable cells were reduced to 6% of the initial concentrations in the presence of 0.2g/ml TiO2 after a 30 min of treatment period, while only an 18% reduction was observed in the absence of TiO2 . The potency of the disinfection could be enhanced, to some extent, by increasing the amount of TiO2 used. Cell concentrations were decreased by an order of 3 within 30 min of treatment in the presence of 1.0 g/ml TiO2 . The disinfection power in the presence of TiO2 versus Al2O3 was also compared and the findings showed that TiO2 induced a higher cell killing. No significant effect of initial cell concentration on the disinfection was found in the range of 10(2)-10(7) CFU/ml after a 30 min of treatment period. The mechanism of cell killing was investigated by examining the effects of OH radical scavengers such as ascorbic acid, histidine and glutathione. The disinfection power was reduced in samples that contained these radical scavengers, thus indicating the importance of OH radicals.
Collapse
Affiliation(s)
- Mahmoud Farshbaf Dadjour
- Division of Biological Measurement and Applications, Institute of Nature and Environmental Technology, Kanazawa University, Kanazawa, 920-1192, Japan
| | | | | | | | | |
Collapse
|
37
|
Dadjour MF, Ogino C, Matsumura S, Shimizu N. Kinetics of disinfection of Escherichia coli by catalytic ultrasonic irradiation with TiO2. Biochem Eng J 2005. [DOI: 10.1016/j.bej.2005.04.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
38
|
Lonnen J, Kilvington S, Kehoe SC, Al-Touati F, McGuigan KG. Solar and photocatalytic disinfection of protozoan, fungal and bacterial microbes in drinking water. WATER RESEARCH 2005; 39:877-883. [PMID: 15743634 DOI: 10.1016/j.watres.2004.11.023] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2003] [Revised: 09/16/2004] [Accepted: 11/17/2004] [Indexed: 05/24/2023]
Abstract
The ability of solar disinfection (SODIS) and solar photocatalytic (TiO(2)) disinfection (SPC-DIS) batch-process reactors to inactivate waterborne protozoan, fungal and bacterial microbes was evaluated. After 8 h simulated solar exposure (870 W/m(2) in the 300 nm-10 microm range, 200 W/m(2) in the 300-400 nm UV range), both SPC-DIS and SODIS achieved at least a 4 log unit reduction in viability against protozoa (the trophozoite stage of Acanthamoeba polyphaga), fungi (Candida albicans, Fusarium solani) and bacteria (Pseudomonas aeruginosa, Escherichia coli). A reduction of only 1.7 log units was recorded for spores of Bacillus subtilis. Both SODIS and SPC-DIS were ineffective against the cyst stage of A. polyphaga.
Collapse
Affiliation(s)
- J Lonnen
- Department of Infection, Immunity & Inflammation, Maurice Shock Building, School of Medicine, University of Leicester, Leicester LE1 9HN, UK
| | | | | | | | | |
Collapse
|
39
|
Reed RH. The Inactivation of Microbes by Sunlight: Solar Disinfection as a Water Treatment Process. ADVANCES IN APPLIED MICROBIOLOGY 2004; 54:333-65. [PMID: 15251286 DOI: 10.1016/s0065-2164(04)54012-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Robert H Reed
- Division of Biomedical Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
| |
Collapse
|