1
|
Feketshane Z, Adeyemi SA, Ubanako P, Ndinteh DT, Ray SS, Choonara YE, Aderibigbe BA. Dissolvable sodium alginate-based antibacterial wound dressing patches: Design, characterization, and in vitro biological studies. Int J Biol Macromol 2023; 232:123460. [PMID: 36731706 DOI: 10.1016/j.ijbiomac.2023.123460] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 01/18/2023] [Accepted: 01/25/2023] [Indexed: 02/01/2023]
Abstract
The treatment of infected wounds in patients with highly sensitive skin is challenging. Some of the available wound dressings cause further skin tear and bleeding upon removal thereby hindering the healing process. In this study, dissolvable antibacterial wound dressing patches loaded with cephalexin monohydrate were prepared from different amounts of sodium alginate (SA) and carboxymethyl cellulose (CMC) by the solvent casting evaporation technique. The patches displayed good tensile strength (3.83-13.83 MPa), appropriate thickness (0.09 to 0.31 mm) and good flexibility (74-98 %) suitable for the skin. The patches displayed good biodegradability and low moisture uptake suitable to prevent microbial invasion on the wound dressings upon storage. The release profile of the drug from the patches was sustained in the range of 47-80 % for 48 h, revealing their capability to inhibit bacterial infection. The biological assay showed that the patches did not induce cytotoxic effects on HaCaT cells, revealing good biocompatibility. The antimicrobial effect of the patches on the different strains of bacteria used in the study was significant. The cell migration (66.7-74.3 %) to the scratched gap was promising revealing the patches' capability to promote wound closure. The results obtained show that the wound dressings are potential materials for the treatment of infected wounds.
Collapse
Affiliation(s)
- Z Feketshane
- Department of Chemistry, University of Fort Hare, Alice Campus, Alice, Eastern Cape, South Africa
| | - S A Adeyemi
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Science, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - P Ubanako
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Science, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - D T Ndinteh
- Department of Applied Chemistry, University of Johannesburg, Doornfontein Campus, Johannesburg, South Africa
| | - S S Ray
- DST/CSIR National Centre for Nanostructured Materials, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - Y E Choonara
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Science, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - B A Aderibigbe
- Department of Chemistry, University of Fort Hare, Alice Campus, Alice, Eastern Cape, South Africa.
| |
Collapse
|
2
|
Ray SS, Soni R, Huyen DTT, Ravi S, Myung S, Lee CY, Kwon Y. Chemical engineering of electrospun
nanofibrous‐based three‐layered
nonwoven polymeric protective mask for enhanced performance. J Appl Polym Sci 2023. [DOI: 10.1002/app.53584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Saikat Sinha Ray
- Department of Urban and Environmental Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan South Korea
| | - Ritesh Soni
- School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan South Korea
| | - Dao Thi Thanh Huyen
- Department of Urban and Environmental Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan South Korea
| | - Srinath Ravi
- Department of Urban and Environmental Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan South Korea
| | - Suwan Myung
- Research Center for Bio‐based Chemistry Korea Research Institute of Chemical Technology (KRICT) Ulsan South Korea
| | - Chang Young Lee
- School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan South Korea
| | - Young‐Nam Kwon
- Department of Urban and Environmental Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan South Korea
| |
Collapse
|
3
|
Ganesapillai M, Mondal B, Sarkar I, Sinha A, Ray SS, Kwon YN, Nakamura K, Govardhan K. The face behind the Covid-19 mask - A comprehensive review. Environ Technol Innov 2022; 28:102837. [PMID: 35879973 PMCID: PMC9299984 DOI: 10.1016/j.eti.2022.102837] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/16/2022] [Accepted: 07/16/2022] [Indexed: 05/07/2023]
Abstract
The threat of epidemic outbreaks like SARS-CoV-2 is growing owing to the exponential growth of the global population and the continual increase in human mobility. Personal protection against viral infections was enforced using ambient air filters, face masks, and other respiratory protective equipment. Available facemasks feature considerable variation in efficacy, materials usage and characteristic properties. Despite their widespread use and importance, face masks pose major potential threats due to the uncontrolled manufacture and disposal techniques. Improper solid waste management enables viral propagation and increases the volume of associated biomedical waste at an alarming rate. Polymers used in single-use face masks include a spectrum of chemical constituents: plasticisers and flame retardants leading to health-related issues over time. Despite ample research in this field, the efficacy of personal protective equipment and its impact post-disposal is yet to be explored satisfactorily. The following review assimilates information on the different forms of personal protective equipment currently in use. Proper waste management techniques pertaining to such special wastes have also been discussed. The study features a holistic overview of innovations made in face masks and their corresponding impact on human health and environment. Strategies with SDG3 and SDG12, outlining safe and proper disposal of solid waste, have also been discussed. Furthermore, employing the CFD paradigm, a 3D model of a face mask was created based on fluid flow during breathing techniques. Lastly, the review concludes with possible future advancements and promising research avenues in personal protective equipment.
Collapse
Affiliation(s)
- Mahesh Ganesapillai
- Mass Transfer Group, School of Chemical Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Bidisha Mondal
- Mass Transfer Group, School of Chemical Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Ishita Sarkar
- Mass Transfer Group, School of Chemical Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Aritro Sinha
- Mass Transfer Group, School of Chemical Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, India
| | - Saikat Sinha Ray
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, Republic of Korea
| | - Young-Nam Kwon
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, Republic of Korea
| | - Kazuho Nakamura
- Faculty of Engineering, Division of Material Science and Chemical Engineering, Yokohama National University, Tokiwadai, Yokohama, Kanagawa 240-8501, Japan
| | - K Govardhan
- Department of Micro and Nano-Electronics, School of Electronics Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, India
| |
Collapse
|
4
|
Huyen DTT, Ray SS, Kim I, Kim M, Kwon Y. Structured pattern hollow fiber membrane designed via reverse thermally induced phase separation method for ultrafiltration applications. J Appl Polym Sci 2022. [DOI: 10.1002/app.52680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dao Thi Thanh Huyen
- Department of Urban and Environmental Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
| | - Saikat Sinha Ray
- Department of Urban and Environmental Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
| | - In‐Chul Kim
- Membrane Research Center Korea Research Institute of Chemical Technology Daejeon Republic of Korea
| | | | - Young‐Nam Kwon
- Department of Urban and Environmental Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
| |
Collapse
|
5
|
Ray SS, Lee HK, Huyen DTT, Chen SS, Kwon YN. Microplastics waste in environment: A perspective on recycling issues from PPE kits and face masks during the COVID-19 pandemic. Environ Technol Innov 2022; 26:102290. [PMID: 35036477 PMCID: PMC8748211 DOI: 10.1016/j.eti.2022.102290] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 12/28/2021] [Accepted: 01/05/2022] [Indexed: 05/06/2023]
Abstract
During the COVID-19 pandemic, the extensive use of face masks and protective personal equipment (PPE) kits has led to increasing degree of microplastic pollution (MP) because they are typically discarded into the seas, rivers, streets, and other parts of the environment. Currently, microplastic (MP) pollution has a negative impact on the environment because of high-level fragmentation. Typically, MP pollution can be detected by various techniques, such as microscopic analysis, density separation, and Fourier transform infrared spectrometry. However, there are limited studies on disposable face masks and PPE kits. A wide range of marine species ingest MPs in the form of fibers and fragments, which directly affect the environment and human health; thus, more research and development are needed on the effect of MP pollution on human health. This article provides a perspective on the origin and distribution of MP pollution in waterbodies (e.g., rivers, ponds, lakes, and seas) and wastewater treatment plants, and reviews the possible remediation of MP pollution related to the excessive disposal of face masks and PPE kits to aquatic environments.
Collapse
Affiliation(s)
- Saikat Sinha Ray
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), South Korea
| | - Hyung Kae Lee
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), South Korea
| | - Dao Thi Thanh Huyen
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), South Korea
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taiwan
| | - Young-Nam Kwon
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), South Korea
| |
Collapse
|
6
|
Sinha Ray S, Dommati H, Wang JC, Lee HK, Park YI, Park H, Kim IC, Chen SS, Kwon YN. Facile approach for designing a novel micropatterned antiwetting membrane by utilizing 3D printed molds for improved desalination performance. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2021.119641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
7
|
Simha P, Barton MA, Perez-Mercado LF, McConville JR, Lalander C, Magri ME, Dutta S, Kabir H, Selvakumar A, Zhou X, Martin T, Kizos T, Kataki R, Gerchman Y, Herscu-Kluska R, Alrousan D, Goh EG, Elenciuc D, Głowacka A, Korculanin L, Tzeng RV, Ray SS, Niwagaba C, Prouty C, Mihelcic JR, Vinnerås B. Erratum to "Willingness among food consumers to recycle human urine as crop fertiliser: Evidence from a multinational survey" [Sci. Total Environ. 765 (2021), 144438]. Sci Total Environ 2021; 790:148318. [PMID: 34144784 DOI: 10.1016/j.scitotenv.2021.148318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- Prithvi Simha
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden.
| | - Melissa A Barton
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Luis Fernando Perez-Mercado
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden; Center for Water and Environmental Sanitation (Centro de Aguas y Saneamiento Ambiental, CASA), Universidad Mayor de San Simon, Calle Sucre y Parque Latorre, Cochabamba, Bolivia
| | - Jennifer R McConville
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Cecilia Lalander
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Maria Elisa Magri
- Universidade Federal de Santa Catarina, Department of Sanitary and Environmental Engineering, Florianópolis, Brazil
| | - Shanta Dutta
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Humayun Kabir
- Department of Agricultural Economics, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | | | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Tristan Martin
- Université Paris-Saclay, INRAE, AgroParisTech, UMR ECOSYS, Avenue Lucien Bretignières, 78850 Thiverval-Grignon, France
| | - Thanasis Kizos
- Department of Geography, University of the Aegean, GR-81100 Mytilene, Greece
| | - Rupam Kataki
- Department of Energy, Tezpur University, Tezpur, India
| | - Yoram Gerchman
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon 36006, Israel; Oranim College, Kiryat Tivon 36006, Israel
| | | | - Dheaya Alrousan
- Department of Water Management and Environment, Faculty of Natural Resources and Environment, The Hashemite University, P.O. Box 150459, Zarqa 13115, Jordan
| | - Eng Giap Goh
- Faculty of Ocean Engineering Technology and Informatics, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia
| | - Daniela Elenciuc
- University of Academy of Sciences of Moldova, Chișinău, Moldavia
| | - Aleksandra Głowacka
- University of Life Sciences in Lublin, Faculty of Agrobioengineering, 15 Akademicka Street, 20-950 Lublin, Poland
| | - Laura Korculanin
- IADE - Universidade Europeia, Av. D. Carlos I, 4, 1200-649 Lisbon, Portugal
| | - Rongyu Veneta Tzeng
- International Institute for Industrial Environmental Economics (IIIEE), Lund University, Lund, Sweden
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Charles Niwagaba
- Department of Civil and Environmental Engineering, College of Engineering, Design, Art and Technology (CEDAT), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Christine Prouty
- Department of Civil and Environmental Engineering, University of South Florida, Tampa, FL 33620, United States
| | - James R Mihelcic
- Department of Civil and Environmental Engineering, University of South Florida, Tampa, FL 33620, United States
| | - Björn Vinnerås
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| |
Collapse
|
8
|
Simha P, Barton MA, Perez-Mercado LF, McConville JR, Lalander C, Magri ME, Dutta S, Kabir H, Selvakumar A, Zhou X, Martin T, Kizos T, Kataki R, Gerchman Y, Herscu-Kluska R, Alrousan D, Goh EG, Elenciuc D, Głowacka A, Korculanin L, Tzeng RV, Ray SS, Niwagaba C, Prouty C, Mihelcic JR, Vinnerås B. Willingness among food consumers to recycle human urine as crop fertiliser: Evidence from a multinational survey. Sci Total Environ 2021; 765:144438. [PMID: 33418332 DOI: 10.1016/j.scitotenv.2020.144438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 10/03/2020] [Revised: 11/22/2020] [Accepted: 12/07/2020] [Indexed: 06/12/2023]
Abstract
Source-separating sanitation systems offer the possibility of recycling nutrients present in wastewater as crop fertilisers. Thereby, they can reduce agriculture's impacts on global sources, sinks, and cycles for nitrogen and phosphorous, as well as their associated environmental costs. However, it has been broadly assumed that people would be reluctant to perform the new sanitation behaviours that are necessary for implementing such systems in practice. Yet, few studies have tried to systematically gather evidence in support of this assumption. To address this gap, we surveyed 3763 people at 20 universities in 16 countries using a standardised questionnaire. We identified and systematically assessed cross-cultural and country-level explanatory factors that were strongly associated with people's willingness to consume food grown using human urine as fertiliser. Overall, 68% of the respondents favoured recycling human urine, 59% stated a willingness to eat urine-fertilised food, and only 11% believed that urine posed health risks that could not be mitigated by treatment. Most people did not expect to pay less for urine-fertilised food, but only 15% were willing to pay a price premium. Consumer perceptions were found to differ greatly by country and the strongest predictive factors for acceptance overall were cognitive factors (perceptions of risks and benefits) and social norms. Increasing awareness and building trust among consumers about the effectiveness of new sanitation systems via cognitive and normative messaging can help increase acceptance. Based on our findings, we believe that in many countries, acceptance by food consumers will not be the major social barrier to closing the loop on human urine. That a potential market exists for urine-fertilised food, however, needs to be communicated to other stakeholders in the sanitation service chain.
Collapse
Affiliation(s)
- Prithvi Simha
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden.
| | - Melissa A Barton
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Luis Fernando Perez-Mercado
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden; Center for Water and Environmental Sanitation (Centro de Aguas y Saneamiento Ambiental, CASA), Universidad Mayor de San Simon, Calle Sucre y Parque Latorre, Cochabamba, Bolivia
| | - Jennifer R McConville
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Cecilia Lalander
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| | - Maria Elisa Magri
- Universidade Federal de Santa Catarina, Department of Sanitary and Environmental Engineering, Florianópolis, Brazil
| | - Shanta Dutta
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Humayun Kabir
- Department of Agricultural Economics, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | | | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Tristan Martin
- Université Paris-Saclay, INRAE, AgroParisTech, UMR ECOSYS, Avenue Lucien Bretignières, 78850 Thiverval-Grignon, France
| | - Thanasis Kizos
- Department of Geography, University of the Aegean, GR-81100 Mytilene, Greece
| | - Rupam Kataki
- Department of Energy, Tezpur University, Tezpur, India
| | - Yoram Gerchman
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon 36006, Israel; Oranim College, Kiryat Tivon 36006, Israel
| | | | - Dheaya Alrousan
- Department of Water Management and Environment, Faculty of Natural Resources and Environment, The Hashemite University, P.O. Box 150459, Zarqa 13115, Jordan
| | - Eng Giap Goh
- Faculty of Ocean Engineering Technology and Informatics, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia
| | | | - Aleksandra Głowacka
- University of Life Sciences in Lublin, Faculty of Agrobioengineering, 15 Akademicka Street, 20-950 Lublin, Poland
| | - Laura Korculanin
- IADE - Universidade Europeia, Av. D. Carlos I, 4, 1200-649 Lisbon, Portugal
| | - Rongyu Veneta Tzeng
- International Institute for Industrial Environmental Economics (IIIEE), Lund University, Lund, Sweden
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Charles Niwagaba
- Department of Civil and Environmental Engineering, College of Engineering, Design, Art and Technology (CEDAT), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Christine Prouty
- Department of Civil and Environmental Engineering, University of South Florida, Tampa, FL 33620, United States
| | - James R Mihelcic
- Department of Civil and Environmental Engineering, University of South Florida, Tampa, FL 33620, United States
| | - Björn Vinnerås
- Swedish University of Agricultural Sciences, Department of Energy and Technology, Box 7032, SE-750 07 Uppsala, Sweden
| |
Collapse
|
9
|
Barton MA, Simha P, Magri ME, Dutta S, Kabir H, Selvakumar A, Zhou X, Lv Y, Martin T, Kizos T, Triantafyllou E, Kataki R, Gerchman Y, Herscu-Kluska R, Alrousan D, Dalahmeh S, Goh EG, Elenciuc D, Głowacka A, Korculanin L, Tzeng RV, Ray SS, Ganesapillai M, Niwagaba C, Prouty C, Mihelcic JR, Vinnerås B. Attitudes of food consumers at universities towards recycling human urine as crop fertiliser: A multinational survey dataset. Data Brief 2021; 35:106794. [PMID: 33604424 PMCID: PMC7875816 DOI: 10.1016/j.dib.2021.106794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/14/2021] [Accepted: 01/21/2021] [Indexed: 11/20/2022] Open
Abstract
We present here a data set generated from a multinational survey on opinions of university community members on the prospect of consuming food grown with human urine as fertiliser and about their urine recycling perceptions in general. The data set comprises answers from 3,763 university community members (students, faculty/researchers, and staff) from 20 universities in 16 countries and includes demographic variables (age bracket, gender, type of settlement of origin, academic discipline, and role in the university). Questions were designed based on Ajzen's theory of planned behaviour to elicit information about three components of behavioural intention-attitudes, subjective norms, and perceived behavioural control. Survey questions covered perceived risks and benefits (attitudes), perceptions of colleagues (injunctive social norm) and willingness to consume food grown with cow urine/faeces (descriptive social norm), and willingness to pay a price premium for food grown with human urine as fertiliser (perceived behavioural control). We also included a question about acceptable urine recycling and disposal options and assessed general environmental outlook via the 15-item revised New Ecological Paradigm (NEP) scale. Data were collected through a standardised survey instrument translated into the relevant languages and then administered via an online form. Invitations to the survey were sent by email to university mailing lists or to a systematic sample of the university directory. Only a few studies on attitudes towards using human urine as fertiliser have been conducted previously. The data described here, which we analysed in "Willingness among food consumers at universities to recycle human urine as crop fertiliser: Evidence from a multinational survey" [1], may be used to further understand potential barriers to acceptance of new sanitation systems based on wastewater source separation and urine recycling and can help inform the design of future sociological studies.
Collapse
Affiliation(s)
- Melissa A. Barton
- Department of Energy and Technology, Swedish University of Agricultural Sciences, P.O. Box 7032, SE–75007 Uppsala, Sweden
| | - Prithvi Simha
- Department of Energy and Technology, Swedish University of Agricultural Sciences, P.O. Box 7032, SE–75007 Uppsala, Sweden
| | - Maria Elisa Magri
- Department of Sanitary and Environmental Engineering, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Shanta Dutta
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Humayun Kabir
- Department of Agricultural Economics, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | | | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Yaping Lv
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Tristan Martin
- Université Paris-Saclay, INRAE, AgroParisTech, UMR ECOSYS, Avenue Lucien Bretignières, 78850 Thiverval-Grignon, France
| | - Thanasis Kizos
- Department of Geography, University of the Aegean, GR-81100 Mytilene, Greece
| | | | - Rupam Kataki
- Department of Energy, Tezpur University, Napam, Tezpur 784 028 Assam, India
| | - Yoram Gerchman
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa at Oranim, Tivon 36006, Israel
- Oranim College, Kiryat Tivon 36006, Israel
| | | | - Dheaya Alrousan
- Department of Water Management and Environment, Faculty of Natural Resources and Environment, The Hashemite University, P.O. Box 150459, Zarqa 13115, Jordan
| | - Sahar Dalahmeh
- Department of Energy and Technology, Swedish University of Agricultural Sciences, P.O. Box 7032, SE–75007 Uppsala, Sweden
| | - Eng Giap Goh
- Faculty of Ocean Engineering Technology and Informatics, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia
| | | | - Aleksandra Głowacka
- Faculty of Agrobioengineering, University of Life Sciences in Lublin, 15 Akademicka Street, 20-950 Lublin, Poland
| | - Laura Korculanin
- IADE – Universidade Europeia, Av. D. Carlos I, 4, 1200-649 Lisbon, Portugal
| | - Rongyu Veneta Tzeng
- International Institute for Industrial Environmental Economics (IIIEE), Lund University, Lund, Sweden
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Mahesh Ganesapillai
- Mass Transfer Group, School of Chemical Engineering, Vellore Institute of Technology, Vellore, India
| | - Charles Niwagaba
- Department of Civil and Environmental Engineering, College of Engineering, Design, Art and Technology (CEDAT), Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Christine Prouty
- Department of Civil and Environmental Engineering, University of South Florida, 4202 E. Fowler Ave., Tampa, Florida 33620, United States
| | - James R. Mihelcic
- Department of Civil and Environmental Engineering, University of South Florida, 4202 E. Fowler Ave., Tampa, Florida 33620, United States
| | - Björn Vinnerås
- Department of Energy and Technology, Swedish University of Agricultural Sciences, P.O. Box 7032, SE–75007 Uppsala, Sweden
| |
Collapse
|
10
|
Chang HM, Chen SS, Chen YT, Chang WS, Li CW, Nguyen NC, Ray SS, Cao DTN. Recovery of iodide as triiodide from thin-film transistor liquid crystal display wastewater by forward osmosis. J Hazard Mater 2021; 403:123637. [PMID: 32818831 DOI: 10.1016/j.jhazmat.2020.123637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/31/2020] [Accepted: 08/02/2020] [Indexed: 06/11/2023]
Abstract
Triiodide, a larger charged molecule compared to iodide, is thermodynamically favored with the presence of both iodide and iodine, and is easier to be retained by membrane processes. For the first time, iodide was recovered in the form of triiodide by forward osmosis (FO) for thin-film transistor liquid crystal display industries by preoxidation of iodide to triiodide. Partial oxidation by NaOCl was used to convert the iodide to iodine and then to form triiodide. Ethylenediaminetetraacetic acid disodium salt (EDTA-2Na), a commonly used chelating agent in the industry, was used as the draw solute because of its low reverse salt flux. The results revealed that the ideal efficiency of iodide recovery was at pH 3 with a preoxidation (adding 0.0150 M NaClO) for the 0.048 M iodide wastewater with a recovery of 98.5%. Additionally, the Pourbaix diagram and starch indicator were used to verify the formation of triiodide. Membrane distillation was demonstrated to recover the EDTA-2Na draw solute, and more than 99% of recoveries for the draw solutes with initial water flux of 12.0 L/m2 h were achieved, indicating that simultaneous recovery of the EDTA-2Na draw solute and water is feasible.
Collapse
Affiliation(s)
- Hau-Ming Chang
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan.
| | - Yu-Ting Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | | | - Chi-Wang Li
- Department of Water Resources and Environmental Engineering, Tamkang University, New Taipei City, Taiwan
| | - Nguyen Cong Nguyen
- Faculty of Environment and Natural Resources, Dalat University, Viet Nam
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Dan Thanh Ngoc Cao
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| |
Collapse
|
11
|
Ray SS, Park YI, Park H, Nam SE, Kim IC, Kwon YN. Surface innovation to enhance anti-droplet and hydrophobic behavior of breathable compressed-polyurethane masks. Environ Technol Innov 2020; 20:101093. [PMID: 32835034 PMCID: PMC7410795 DOI: 10.1016/j.eti.2020.101093] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/03/2020] [Accepted: 08/03/2020] [Indexed: 05/09/2023]
Abstract
With the emergence of the coronavirus disease (COVID-19), it is essential that face masks demonstrating significant anti-droplet and hydrophobic characteristics are developed and distributed. In this study, a commercial compressed-polyurethane (C-PU) mask was modified by applying a hydrophobic and anti-droplet coating using a silica sol, which was formed by the hydrolysis of tetraethoxysilane (TEOS) under alkaline conditions and hydrolyzed hexadecyltrimethoxysilane (HDTMS) to achieve hydrophobization. The modified mask (C-PU/Si/HDTMS) demonstrated good water repellency resulting in high water contact angle (132°) and low sliding angle (17°). Unmodified and modified masks were characterized using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). A drainage test confirmed the strong interaction between the mask surface and coating. Moreover, the coating had negligible effect on the average pore size of the C-PU mask, which retained its high breathability after modification. The application of this coating is a facile approach to impart anti-droplet, hydrophobic, and self-cleaning characteristics to C-PU masks.
Collapse
Affiliation(s)
- Saikat Sinha Ray
- School of Urban and Environmental Engineering (UEE), Ulsan National Institute of Science and Technology (UNIST), Republic of Korea
| | - You-In Park
- Membrane Research Center, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Hosik Park
- Membrane Research Center, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Seung-Eun Nam
- Membrane Research Center, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - In-Chul Kim
- Membrane Research Center, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Young-Nam Kwon
- School of Urban and Environmental Engineering (UEE), Ulsan National Institute of Science and Technology (UNIST), Republic of Korea
| |
Collapse
|
12
|
Le HQ, Nguyen TXQ, Chen SS, Duong CC, Cao TND, Chang HM, Ray SS, Nguyen NC. Application of progressive freezing on forward osmosis draw solute recovery. Environ Sci Pollut Res Int 2020; 27:34664-34674. [PMID: 31401797 DOI: 10.1007/s11356-019-06079-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 01/03/2019] [Accepted: 07/26/2019] [Indexed: 06/10/2023]
Abstract
Progressive freezing is a solvent purification technology with low energy requirements and high concentration efficiency. Although these advantages make it a promising technology, the technique has never been explored for draw solution recovery for forward osmosis (FO). Hence, in this study, the progressive freezing process was used to concentrate three common diluted draw solutions: NaCl, MgCl2, and EDTA-2Na with different ice front speeds, stirring rates, and initial draw solution concentrations. Effective partition and intrinsic partition constants were also evaluated. The results reveal that the freezing process can achieve a draw solution recovery rate of 99.73%, 99.06%, and 98.65% with NaCl, MgCl2, and EDTA-2Na, respectively, using an ice front speed of 0.5 cm/h, a stirring rate of 2.62 m/s, and 30% of percentage of ice phase. Higher concentration efficiency for NaCl and MgCl2 was achieved due to the high solubility of NaCl and MgCl2 increased solute diffusion into the liquid phase solutions. The concentration factors for all three draw solutions exceeded 1.9, indicating that the draw solutes could be reused for the FO process. In addition, the two mass transfer coefficients depended on the ice front speed and the stirring rates were also obtained for scaling up the experiment in the future.
Collapse
Affiliation(s)
- Huy Quang Le
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd, Taipei, 10608, Taiwan
- Faculty of Environment and Natural Resources, Dalat University, 01 Phu Dong Thien Vuong Street, Da Lat City, 66000, Vietnam
| | - Thi Xuan Quynh Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd, Taipei, 10608, Taiwan
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd, Taipei, 10608, Taiwan.
| | - Chinh Cong Duong
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd, Taipei, 10608, Taiwan
- Southern Institute of Water Resources Research, 658 Vo Van Kiet Street, District 5, Ho Chi Minh City, 700000, Vietnam
| | - Thanh Ngoc-Dan Cao
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd, Taipei, 10608, Taiwan
- Nguyen Tat Thanh University, 300A Nguyen Tat Thanh Street, District 4, Ho Chi Minh City, 700000, Vietnam
| | - Hau-Ming Chang
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd, Taipei, 10608, Taiwan
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd, Taipei, 10608, Taiwan
| | - Nguyen Cong Nguyen
- Faculty of Environment and Natural Resources, Dalat University, 01 Phu Dong Thien Vuong Street, Da Lat City, 66000, Vietnam
| |
Collapse
|
13
|
Sinha Ray S, Singh Bakshi H, Dangayach R, Singh R, Deb CK, Ganesapillai M, Chen SS, Purkait MK. Recent Developments in Nanomaterials-Modified Membranes for Improved Membrane Distillation Performance. Membranes (Basel) 2020; 10:E140. [PMID: 32635417 PMCID: PMC7408142 DOI: 10.3390/membranes10070140] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [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: 06/09/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 02/03/2023]
Abstract
Membrane distillation (MD) is a thermally induced membrane separation process that utilizes vapor pressure variance to permeate the more volatile constituent, typically water as vapor, across a hydrophobic membrane and rejects the less volatile components of the feed. Permeate flux decline, membrane fouling, and wetting are some serious challenges faced in MD operations. Thus, in recent years, various studies have been carried out on the modification of these MD membranes by incorporating nanomaterials to overcome these challenges and significantly improve the performance of these membranes. This review provides a comprehensive evaluation of the incorporation of new generation nanomaterials such as quantum dots, metalloids and metal oxide-based nanoparticles, metal organic frameworks (MOFs), and carbon-based nanomaterials in the MD membrane. The desired characteristics of the membrane for MD operations, such as a higher liquid entry pressure (LEPw), permeability, porosity, hydrophobicity, chemical stability, thermal conductivity, and mechanical strength, have been thoroughly discussed. Additionally, methodologies adopted for the incorporation of nanomaterials in these membranes, including surface grafting, plasma polymerization, interfacial polymerization, dip coating, and the efficacy of these modified membranes in various MD operations along with their applications are addressed. Further, the current challenges in modifying MD membranes using nanomaterials along with prominent future aspects have been systematically elaborated.
Collapse
Affiliation(s)
- Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei City 106, Taiwan; (H.S.B.); (R.D.); (R.S.)
| | - Harshdeep Singh Bakshi
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei City 106, Taiwan; (H.S.B.); (R.D.); (R.S.)
- School of Chemical Engineering, Vellore Institute of Technology (VIT), Vellore 632014, India;
| | - Raghav Dangayach
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei City 106, Taiwan; (H.S.B.); (R.D.); (R.S.)
- School of Chemical Engineering, Vellore Institute of Technology (VIT), Vellore 632014, India;
| | - Randeep Singh
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei City 106, Taiwan; (H.S.B.); (R.D.); (R.S.)
- Department of Chemical Engineering, Indian Institute of Technology, Guwahati 781039, India;
| | - Chinmoy Kanti Deb
- School of Chemical Engineering, Vellore Institute of Technology (VIT), Vellore 632014, India;
| | - Mahesh Ganesapillai
- School of Chemical Engineering, Vellore Institute of Technology (VIT), Vellore 632014, India;
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei City 106, Taiwan; (H.S.B.); (R.D.); (R.S.)
| | - Mihir Kumar Purkait
- Department of Chemical Engineering, Indian Institute of Technology, Guwahati 781039, India;
| |
Collapse
|
14
|
Aderibigbe B, Mbese Z, Peteni S, Fonkui YT, Fotsing MC, Ray SS, Ndinteh DT. Carbopol-mastic gum/silver nanoparticle-based topical gels. Pharmacogn Mag 2020. [DOI: 10.4103/pm.pm_76_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
|
15
|
Ray SS, Lee HK, Kwon YN. Review on Blueprint of Designing Anti-Wetting Polymeric Membrane Surfaces for Enhanced Membrane Distillation Performance. Polymers (Basel) 2019; 12:E23. [PMID: 31877628 PMCID: PMC7023606 DOI: 10.3390/polym12010023] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/06/2019] [Accepted: 12/07/2019] [Indexed: 12/14/2022] Open
Abstract
Recently, membrane distillation (MD) has emerged as a versatile technology for treating saline water and industrial wastewater. However, the long-term use of MD wets the polymeric membrane and prevents the membrane from working as a semi-permeable barrier. Currently, the concept of antiwetting interfaces has been utilized for reducing the wetting issue of MD. This review paper discusses the fundamentals and roles of surface energy and hierarchical structures on both the hydrophobic characteristics and wetting tolerance of MD membranes. Designing stable antiwetting interfaces with their basic working principle is illustrated with high scientific discussions. The capability of antiwetting surfaces in terms of their self-cleaning properties has also been demonstrated. This comprehensive review paper can be utilized as the fundamental basis for developing antiwetting surfaces to minimize fouling, as well as the wetting issue in the MD process.
Collapse
Affiliation(s)
- Saikat Sinha Ray
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| | - Hyung-Kae Lee
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| | - Young-Nam Kwon
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| |
Collapse
|
16
|
Olaiya NG, Surya I, Oke PK, Rizal S, Sadiku ER, Ray SS, Farayibi PK, Hossain MS, Abdul Khalil HPS. Properties and Characterization of a PLA-Chitin-Starch Biodegradable Polymer Composite. Polymers (Basel) 2019; 11:polym11101656. [PMID: 31614623 PMCID: PMC6836172 DOI: 10.3390/polym11101656] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/08/2019] [Accepted: 10/08/2019] [Indexed: 11/16/2022] Open
Abstract
This paper presents a comparison on the effects of blending chitin and/or starch with poly(lactic acid) (PLA). Three sets of composites (PLA–chitin, PLA–starch and PLA–chitin–starch) with 92%, 94%, 96% and 98% PLA by weight were prepared. The percentage weight (wt.%) amount of the chitin and starch incorporated ranges from 2% to 8%. The mechanical, dynamic mechanical, thermal and microstructural properties were analyzed. The results from the tensile strength, yield strength, Young’s modulus, and impact showed that the PLA–chitin–starch blend has the best mechanical properties compared to PLA–chitin and PLA–starch blends. The dynamic mechanical analysis result shows a better damping property for PLA–chitin than PLA–chitin–starch and PLA–starch. On the other hand, the thermal property analysis from thermogravimetry analysis (TGA) shows no significant improvement in a specific order, but the glass transition temperature of the composite increased compared to that of neat PLA. However, the degradation process was found to start with PLA–chitin for all composites, which suggests an improvement in PLA degradation. Significantly, the morphological analysis revealed a uniform mix with an obvious blend network in the three composites. Interestingly, the network was more significant in the PLA–chitin–starch blend, which may be responsible for its significantly enhanced mechanical properties compared with PLA–chitin and PLA–starch samples.
Collapse
Affiliation(s)
- N G Olaiya
- Department of Industrial and Production Engineering, Federal University of Technology, P.M.B.740 Akure, Nigeria.
- School of Industrial Technology, Universiti Sains Malaysia,11800 Penang, Malaysia.
| | - Indra Surya
- Department of Chemical Engineering, Universitas Sumatera Utara, Medan 20155, Indonesia.
| | - P K Oke
- Department of Industrial and Production Engineering, Federal University of Technology, P.M.B.740 Akure, Nigeria.
| | - Samsul Rizal
- Department of Mechanical Engineering, Universitas Syiah Kuala, Banda Aceh 23111, Indonesia.
| | - E R Sadiku
- Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, P.M.B. X680 Pretoria, South Africa.
| | - S S Ray
- DST-/CSIR National Centre for Nanostructured Materials, Council for Scientific and Industrial Research, Pretoria 0001, South Africa.
| | - P K Farayibi
- Department of Industrial and Production Engineering, Federal University of Technology, P.M.B.740 Akure, Nigeria.
| | - Md Sohrab Hossain
- School of Industrial Technology, Universiti Sains Malaysia,11800 Penang, Malaysia.
| | - H P S Abdul Khalil
- School of Industrial Technology, Universiti Sains Malaysia,11800 Penang, Malaysia.
| |
Collapse
|
17
|
Chang HM, Sun YC, Chien IC, Chang WS, Ray SS, Cao DTN, Cong Duong C, Chen SS. Innovative upflow anaerobic sludge osmotic membrane bioreactor for wastewater treatment. Bioresour Technol 2019; 287:121466. [PMID: 31108413 DOI: 10.1016/j.biortech.2019.121466] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [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: 03/25/2019] [Revised: 05/09/2019] [Accepted: 05/11/2019] [Indexed: 06/09/2023]
Abstract
A novel upflow anaerobic sludge-forward osmotic membrane bioreactor was developed for simultaneous wastewater treatment, membrane fouling reduction, and nutrient recovery. An upflow anaerobic sludge blanket (UASB) reactor was incorporated into the system, suspending the anaerobic sludge at the bottom of the reactor. A forward osmosis membrane replaced the traditional three-phase separator of the UASB technology. The removals of chemical oxygen demand, PO43-, and NH4+ were all more than 95% with low membrane fouling in this system. Halotolerant Fusibacter, which can ferment organics to acetate, was increased rapidly from 0.1% to 5% in this saline environment. Acetoclastic Methanosaeta was the most dominant prokaryotes and responsible for majority of methane production. Reduction of membrane fouling in this system was verified by the fluorescence excitation-emission matrix spectrophotometry. Furthermore, phosphorus recovery and salinity build-up mitigation were achieved using periodic microfiltration to recover 57-105 mg/L phosphorus from pH 9 to 12.
Collapse
Affiliation(s)
- Hau-Ming Chang
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Yung-Chun Sun
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - I-Chieh Chien
- Department of Water Resources and Environmental Engineering, Tamkang University, New Taipei City, Taiwan
| | | | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Dan Thanh Ngoc Cao
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan
| | - Chinh Cong Duong
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan; Southern Institute of Water Resources Research, Ho Chih Ming City, Viet Nam
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei, Taiwan.
| |
Collapse
|
18
|
Trivedi J, Singh J, Atray N, Ray SS, Agrawal D. Development of a non-linear growth model for predicting temporal evolution of Scenedesmus obliquus with varying irradiance. Bioprocess Biosyst Eng 2019; 42:2047-2054. [PMID: 31432253 DOI: 10.1007/s00449-019-02194-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/30/2019] [Accepted: 08/08/2019] [Indexed: 11/30/2022]
Abstract
In the present study, the effect of irradiance on growth performance of Scenedesmus obliquus was investigated, and various non-linear growth models were evaluated to predict its temporal evolution. This microalga was cultured in a LED-illuminated flat-panel gas-lift photobioreactor operated in batch mode at varying irradiance ranging from 50 to 200 µmol/m2/s keeping all the other physico-chemical parameters constant. When growth data in terms of optical density were fitted in sigmoidal growth models, three non-linear models, namely, Richards model, Gompertz model, and logistic model, were found to be the best fit. Comparing these models based on statistical information, the logistic model could more appropriately and precisely describe algal growth under varying light intensity. Finally, the parameters of the logistic model were determined using regression analysis and were incorporated in the logistic equation to investigate the kinetic characteristics of S. obliquus. The optimum light intensity (Iopt) for growth was found to be 150 µmol/m2/s, at which a maximum specific growth rate (µopt) of 0.35/day was obtained. The model developed was validated experimentally and could successfully explain the photo-inhibition phenomenon occurring at light intensity above 150 µmol/m2/s.
Collapse
Affiliation(s)
- Jayati Trivedi
- Biofuels Division, CSIR-Indian Institute of Petroleum, Mohkampur, Dehradun, 248005, India. .,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India.
| | - Jasvinder Singh
- Biofuels Division, CSIR-Indian Institute of Petroleum, Mohkampur, Dehradun, 248005, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India
| | - Neeraj Atray
- Biofuels Division, CSIR-Indian Institute of Petroleum, Mohkampur, Dehradun, 248005, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India
| | - S S Ray
- Biofuels Division, CSIR-Indian Institute of Petroleum, Mohkampur, Dehradun, 248005, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India
| | - Deepti Agrawal
- Biofuels Division, CSIR-Indian Institute of Petroleum, Mohkampur, Dehradun, 248005, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, 201002, India
| |
Collapse
|
19
|
Mhlongo GH, Motaung DE, Cummings FR, Swart HC, Ray SS. A highly responsive NH 3 sensor based on Pd-loaded ZnO nanoparticles prepared via a chemical precipitation approach. Sci Rep 2019; 9:9881. [PMID: 31285474 PMCID: PMC6614408 DOI: 10.1038/s41598-019-46247-z] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 06/24/2019] [Indexed: 12/01/2022] Open
Abstract
The gas-detecting ability of nanostructured ZnO has led to significant attention being paid to the development of a unique and effective approach to its synthesis. However, its poor sensitivity, cross-sensitivity to humidity, long response/recovery times and poor selectivity hinder its practical use in environmental and health monitoring. In this context, the addition of noble metals, as dopants or catalysts to modify the ZnO surface has been examined to enhance its sensing performance. Herein, we report preparation of Pd-loaded ZnO nanoparticles via a chemical precipitation approach. Various Pd loadings were employed to produce surface-modified ZnO nanostructure sensors, and their resulting NH3 sensing capabilities both in dry and humid environments were investigated. Through a comparative gas sensing study between the pure and Pd-loaded ZnO sensors upon exposure to NH3 at an optimal operating temperature of 350 °C, the Pd-loaded ZnO sensors were found to exhibit enhanced sensor responses and fast response/recovery times. The influence of Pd loading and its successful incorporation into ZnO nanostructure was examined by X-ray diffraction, high resolution-transmission electron microscopy, and X-ray photoelectron spectroscopy. XPS studies demonstrated that in all samples, Pd existed in two chemical states, namely Pd° and Pd2+. The possible sensing mechanism related to NH3 gas is also discussed in detail.
Collapse
Affiliation(s)
- G H Mhlongo
- DST-CSIR National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, Pretoria, 0001, South Africa. .,Department of Physics, University of the Free State, Bloemfontein, ZA9300, South Africa.
| | - D E Motaung
- DST-CSIR National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, Pretoria, 0001, South Africa.,Department of Physics, University of the Free State, Bloemfontein, ZA9300, South Africa
| | - F R Cummings
- Electron Microscope Unit, University of the Western Cape, Bellville, 7535, South Africa
| | - H C Swart
- Department of Physics, University of the Free State, Bloemfontein, ZA9300, South Africa
| | - S S Ray
- DST-CSIR National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, Pretoria, 0001, South Africa.,Department of Applied Chemistry, University of Johannesburg, Doornfontein, 2028, Johanneburg, South Africa
| |
Collapse
|
20
|
Le HQ, Sowe A, Chen SS, Duong CC, Ray SS, Cao TND, Nguyen NC. Exploring Nanosilver-Coated Hollow Fiber Microfiltration to Mitigate Biofouling for High Loading Membrane Bioreactor. Molecules 2019; 24:E2345. [PMID: 31242707 PMCID: PMC6631756 DOI: 10.3390/molecules24122345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/21/2019] [Accepted: 06/24/2019] [Indexed: 11/16/2022] Open
Abstract
For the first time, a nanosilver-coated hollow fiber microfiltration (MF) was fabricated by a simple chemical reduction method, then tested for membrane biofouling mitigation study under extreme high mixed liquor suspended solid (MLSS) concentration for long term. This study presents a simple and novel technique to modify a commercially available MF membrane using silver nanoparticles (AgNPs) followed by an investigation of mitigating membrane biofouling potentials using this modified membrane to compare with an unmodified membrane for 60-day operation period. The modified membranes showed that AgNPs was attached to the MF-membrane successfully with a high density of 119.85 ± 5.42 mg/m2. After long-term testing of 60 days in membrane bioreactor with a MLSS concentration of 11,000 mg/L, specific flux of the AgNPs coated MF (AgNPs-MF) decreased 59.7%, while the specific flux of the unmodified membrane dropped 81.8%, resulted from the increase of transmembrane vacuum pressure for the AgNPs-MF was lower than that of the unmodified one. The resistance-in-series model was used to calculate the resistance coefficients of membrane modules, and the result showed that the cake layer resistance coefficient of the unmodified membrane was 2.7 times higher than that of the AgNPs-MF after the 60-day operation, confirming that AgNPs displayed great antimicrobial properties to mitigate membrane biofouling under such high MLSS.
Collapse
Affiliation(s)
- Huy Quang Le
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd. Taipei 10608, Taiwan; (H.Q.L.); (A.S.); (C.C.D.); (S.S.R.); (T.N.-D.C.)
- Faculty of Environment and Natural Resources, Dalat University, 01 Phu Dong Thien Vuong Street, Da Lat City 66000, Vietnam;
| | - Alieu Sowe
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd. Taipei 10608, Taiwan; (H.Q.L.); (A.S.); (C.C.D.); (S.S.R.); (T.N.-D.C.)
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd. Taipei 10608, Taiwan; (H.Q.L.); (A.S.); (C.C.D.); (S.S.R.); (T.N.-D.C.)
| | - Chinh Cong Duong
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd. Taipei 10608, Taiwan; (H.Q.L.); (A.S.); (C.C.D.); (S.S.R.); (T.N.-D.C.)
- Southern Institute of Water Resources Research, 658 Vo Van Kiet Street, District 5, Ho Chi Minh City 700000, Vietnam
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd. Taipei 10608, Taiwan; (H.Q.L.); (A.S.); (C.C.D.); (S.S.R.); (T.N.-D.C.)
| | - Thanh Ngoc-Dan Cao
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Zhongxiao E. Rd. Taipei 10608, Taiwan; (H.Q.L.); (A.S.); (C.C.D.); (S.S.R.); (T.N.-D.C.)
- Nguyen Tat Thanh University, 300A Nguyen Tat Thanh Street, District 4, Ho Chi Minh City 700000, Vietnam
| | - Nguyen Cong Nguyen
- Faculty of Environment and Natural Resources, Dalat University, 01 Phu Dong Thien Vuong Street, Da Lat City 66000, Vietnam;
| |
Collapse
|
21
|
Ray SS, Deb CK, Chang H, Chen S, Ganesapillai M. Crosslinked PVDF‐HFP‐based hydrophobic membranes incorporated with CNF for enhanced stability and permeability in membrane distillation. J Appl Polym Sci 2019. [DOI: 10.1002/app.48021] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Saikat Sinha Ray
- Institute of Environmental Engineering and ManagementNational Taipei University of Technology Taipei City‐106 Taiwan
| | - Chinmoy Kanti Deb
- Institute of Environmental Engineering and ManagementNational Taipei University of Technology Taipei City‐106 Taiwan
- Mass Transfer Group, School of Chemical EngineeringVellore Institute of Technology‐ VIT Vellore India
| | - Hau‐Ming Chang
- Institute of Environmental Engineering and ManagementNational Taipei University of Technology Taipei City‐106 Taiwan
| | - Shiao‐Shing Chen
- Institute of Environmental Engineering and ManagementNational Taipei University of Technology Taipei City‐106 Taiwan
| | - Mahesh Ganesapillai
- Mass Transfer Group, School of Chemical EngineeringVellore Institute of Technology‐ VIT Vellore India
| |
Collapse
|
22
|
Dommati H, Ray SS, Wang JC, Chen SS. A comprehensive review of recent developments in 3D printing technique for ceramic membrane fabrication for water purification. RSC Adv 2019; 9:16869-16883. [PMID: 35516413 PMCID: PMC9064412 DOI: 10.1039/c9ra00872a] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/09/2019] [Indexed: 11/21/2022] Open
Abstract
Additive manufacturing (AM), which is also commonly known as 3D printing, provides flexibility in the manufacturing of complex geometric parts at competitive prices and within a low production time. However, AM has not been used to a large extent in filtration and water treatment processes. AM results in the creation of millions of nanofibers that are sublayered on top of each other and compressed into a thin membrane. AM is a novel technique for fabricating filtration membranes with different shapes, sizes and controlled porosity, which cannot be achieved using conventional process such as electrospinning and knife casting. In this paper, we review the advantages and limitations of AM processes for fabricating ceramic membranes. Moreover, a brief background of AM processes is provided, and their future prospects are examined. Due to their potential benefits for fabrication and flexibility with different materials, AM methods are promising in the field of membrane engineering. Additive manufacturing (AM), which is also commonly known as 3D printing, provides flexibility in the manufacturing of complex geometric parts at competitive prices and within a low production time.![]()
Collapse
Affiliation(s)
- Hitesh Dommati
- Department of Mechanical Engineering
- National Taipei University of Technology
- Taiwan
- Additive Manufacturing Center for Mass Customization Production
- National Taipei University of Technology
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taiwan
| | - Jia-Chang Wang
- Department of Mechanical Engineering
- National Taipei University of Technology
- Taiwan
- Additive Manufacturing Center for Mass Customization Production
- National Taipei University of Technology
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taiwan
| |
Collapse
|
23
|
Nguyen NC, Chen SS, Ho ST, Nguyen HT, Ray SS, Nguyen NT, Hsu HT, Le NC, Tran TT. Optimising the recovery of EDTA-2Na draw solution in forward osmosis through direct contact membrane distillation. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
24
|
Nguyen NC, Chen SS, Nguyen HT, Chen YH, Ngo HH, Guo W, Ray SS, Chang HM, Le QH. Applicability of an integrated moving sponge biocarrier-osmotic membrane bioreactor MD system for saline wastewater treatment using highly salt-tolerant microorganisms. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.01.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
25
|
Ray SS, Chen SS, Nguyen NC, Nguyen HT, Dan NP, Thanh BX, Trang LT. Exploration of polyelectrolyte incorporated with Triton-X 114 surfactant based osmotic agent for forward osmosis desalination. J Environ Manage 2018; 209:346-353. [PMID: 29306844 DOI: 10.1016/j.jenvman.2017.12.086] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/27/2017] [Accepted: 12/30/2017] [Indexed: 06/07/2023]
Abstract
Selection of a proper osmotic agent is important to make the forward osmosis (FO) feasible. The objective of this study was to enhance FO by lowering reverse solute flux and maintaining high water flux. Poly(propylene glycol) with molecular weight of 725 Da (PPG-725) was found to possess high osmolality, making it a strong candidate for using as a draw agent. In addition, to reduce the partial leakage of draw solute, a non-ionic surfactant (Triton X-114) has been incorporated. Typically, when the hydrophobic tails of Triton X-114 interacted with the membrane surface, a layer on the surface of membrane is produced to constrict the pores and thus minimize the reverse solute flux. In this study, different concentrations of PPG-725 incorporated with different concentrations of Triton X-114 (0.2-0.8 mM) were used to evaluate their osmotic potentials as draw solute. The specific reverse solute flux (Js/Jw) of 40% PPG-725 doped with Triton X-114 was found to be 0.01 g/L, considerably much lesser than the conventional inorganic draw agents. Finally, membrane distillation operation was utilized as the recovery system in which solute rejection of 97% was achieved for 40% PPG-725/Triton X-114. Therefore, the overall performance supported PPG-725/Triton X-114 as being an efficient draw agent for forward osmosis-membrane distillation hybrid process.
Collapse
Affiliation(s)
- Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan
| | - Shiao Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan.
| | - Nguyen Cong Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan; Faculty of Environment and Natural Resources, Dalat University, Viet Nam
| | - Hau Thi Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan; Faculty of Environment and Natural Resources, Dalat University, Viet Nam
| | - Nguyen Phuoc Dan
- Faculty of Environment & Natural Resources, Ho Chi Minh City University of Technology, 268 Ly Thuong Kiet St, Dist. 10, Ho Chi Minh City, Viet Nam
| | - Bui Xuan Thanh
- Faculty of Environment & Natural Resources, Ho Chi Minh City University of Technology, 268 Ly Thuong Kiet St, Dist. 10, Ho Chi Minh City, Viet Nam
| | - Le Thuy Trang
- Faculty of Environment and Chemical Engineering, Duy Tan University, Viet Nam
| |
Collapse
|
26
|
Saxena RC, Biswal J, Pant HJ, Samantray JS, Sharma SC, Gupta AK, Ray SS. Application of thin layer activation technique for monitoring corrosion of carbon steel in hydrocarbon processing environment. Appl Radiat Isot 2018; 135:201-206. [PMID: 29413838 DOI: 10.1016/j.apradiso.2018.01.044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/19/2018] [Accepted: 01/31/2018] [Indexed: 10/18/2022]
Abstract
Acidic crude oil transportation and processing in petroleum refining and petrochemical operations cause corrosion in the pipelines and associated components. Corrosion monitoring is invariably required to test and prove operational reliability. Thin Layer Activation (TLA) technique is a nuclear technique used for measurement of corrosion and erosion of materials. The technique involves irradiation of material with high energy ion beam from an accelerator and measurement of loss of radioactivity after the material is subjected to corrosive environment. In the present study, TLA technique has been used to monitor corrosion of carbon steel (CS) in crude oil environment at high temperature. Different CS coupons were irradiated with a 13 MeV proton beam to produce Cobalt-56 radioisotope on the surface of the coupons. The corrosion studies were carried out by subjecting the irradiated coupons to a corrosive environment, i.e, uninhibited straight run gas oil (SRGO) containing known amount of naphthenic acid (NA) at high temperature. The effects of different parameters, such as, concentration of NA, temperature and fluid velocity (rpm) on corrosion behaviour of CS were studied.
Collapse
Affiliation(s)
- R C Saxena
- Chemical Sciences Division, Indian Institute of Petroleum, Haridwar Road, Mohkampur, Dehradun 248005, India
| | - Jayashree Biswal
- Isotope and Radiation Application Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - H J Pant
- Isotope and Radiation Application Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India.
| | - J S Samantray
- Isotope and Radiation Application Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - S C Sharma
- Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - A K Gupta
- Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - S S Ray
- Chemical Sciences Division, Indian Institute of Petroleum, Haridwar Road, Mohkampur, Dehradun 248005, India
| |
Collapse
|
27
|
Nguyen NC, Chen SS, Jain S, Nguyen HT, Ray SS, Ngo HH, Guo W, Lam NT, Duong HC. Exploration of an innovative draw solution for a forward osmosis-membrane distillation desalination process. Environ Sci Pollut Res Int 2018; 25:5203-5211. [PMID: 28527139 DOI: 10.1007/s11356-017-9192-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [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: 01/15/2017] [Accepted: 05/02/2017] [Indexed: 06/07/2023]
Abstract
Forward osmosis (FO) has emerged as a viable technology to alleviate the global water crisis. The greatest challenge facing the application of FO technology is the lack of an ideal draw solution with high water flux and low reverse salt flux. Hence, the objective of this study was to enhance FO by lowering reverse salt flux and maintaining high water flux; the method involved adding small concentrations of Al2(SO4)3 to a MgCl2 draw solution. Results showed that 0.5 M MgCl2 mixed with 0.05 M of Al2(SO4)3 at pH 6.5 achieved a lower reverse salt flux (0.53 gMH) than that of pure MgCl2 (1.55 gMH) using an FO cellulose triacetate nonwoven (CTA-NW) membrane. This was due possibly to the flocculation of aluminum hydroxide in the mixed draw solution that constricted membrane pores, resulting in reduced salt diffusion. Moreover, average water fluxes of 4.09 and 1.74 L/m2-h (LMH) were achieved over 180 min, respectively, when brackish water (5 g/L) and sea water (35 g/L) were used as feed solutions. Furthermore, three types of membrane distillation (MD) membranes were selected for draw solution recovery; of these, a polytetrafluoroethylene membrane with a pore size of 0.45 μm proved to be the most effective in achieving a high salt rejection (99.90%) and high water flux (5.41 LMH) in a diluted draw solution.
Collapse
Affiliation(s)
- Nguyen Cong Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei, 106, Taiwan, Republic of China.
- Faculty of Environment and Natural Resources, Dalat University, Dalat, Vietnam.
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei, 106, Taiwan, Republic of China.
| | - Shubham Jain
- School of Civil and Chemical Engineering, VIT University, Vellore, India
| | - Hau Thi Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei, 106, Taiwan, Republic of China
- Faculty of Environment and Natural Resources, Dalat University, Dalat, Vietnam
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei, 106, Taiwan, Republic of China
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW, 2007, Australia.
| | - Wenshan Guo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - Ngoc Tuan Lam
- Faculty of Environment and Natural Resources, Dalat University, Dalat, Vietnam
| | - Hung Cong Duong
- Strategic Water Infrastructure Laboratory, School of Civil Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW, 2522, Australia
| |
Collapse
|
28
|
Ray SS, Chen SS, Chang HM, Dan Thanh CN, Quang Le H, Nguyen NC. Enhanced desalination using a three-layer OTMS based superhydrophobic membrane for a membrane distillation process. RSC Adv 2018; 8:9640-9650. [PMID: 35540818 PMCID: PMC9078671 DOI: 10.1039/c8ra01043a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 02/28/2018] [Indexed: 11/21/2022] Open
Abstract
Superhydrophobic membranes are essential for enhanced desalination by utilizing MD.
Collapse
Affiliation(s)
- Saikat Sinha Ray
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Hau-Ming Chang
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Cao Ngoc Dan Thanh
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Huy Quang Le
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | | |
Collapse
|
29
|
Ray SS, Chen SS, Ngoc Dan CT, Hsu HT, Chang HM, Nguyen NC, Nguyen HT. Casting of a superhydrophobic membrane composed of polysulfone/Cera flava for improved desalination using a membrane distillation process. RSC Adv 2018; 8:1808-1819. [PMID: 35542592 PMCID: PMC9077260 DOI: 10.1039/c7ra12474k] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 12/27/2017] [Indexed: 11/21/2022] Open
Abstract
Superhydrophobic membranes are necessary for effective membrane-based seawater desalination. This paper presents the successful fabrication of a novel electrospun nanofibrous membrane composed of polysulfone and Cera flava, which represents a novel class of enhanced performance membranes consisting of a superhydrophobic nanofibrous layer and hydrophobic polypropylene (PP). Cera flava, which helps lower the surface energy, was found to be the ideal additive for increasing the hydrophobicity of the polysulfone (PSF) polymeric solution because of its components such as long-chain hydrocarbons, free acids, esters, and internal chain methylene carbons. In the fabricated membrane, consisting of 10 v/v% Cera flava, the top PSF–CF nanofibrous layer is active and the lower PP layer is supportive. The hybrid membrane possesses superhydrophobicity, with an average contact angle of approximately 162°, and showed high performance in terms of rejection and water flux. This work also examined the surface area, pore size distribution, fiber diameter, surface roughness, mechanical strength, water flux, and rejection percentage of the membrane. The salt rejection was above 99.8%, and a high permeate flux of approximately 6.4 LMH was maintained for 16 h of operation. Superhydrophobic membranes for effective MD desalination.![]()
Collapse
Affiliation(s)
- Saikat Sinha Ray
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Cao Thanh Ngoc Dan
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Hung-Te Hsu
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Hau-Ming Chang
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | | | - Hau-Thi Nguyen
- Faculty of Environment and Natural Resources
- DaLat University
- Viet Nam
| |
Collapse
|
30
|
Ray SS, Chen SS, Hsu HT, Cao DT, Nguyen HT, Nguyen NC. Uniform hydrophobic electrospun nanofibrous layer composed of polysulfone and sodium dodecyl sulfate for improved desalination performance. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2017.06.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
31
|
Papadaki D, Foteinis S, Mhlongo GH, Nkosi SS, Motaung DE, Ray SS, Tsoutsos T, Kiriakidis G. Life cycle assessment of facile microwave-assisted zinc oxide (ZnO) nanostructures. Sci Total Environ 2017; 586:566-575. [PMID: 28209407 DOI: 10.1016/j.scitotenv.2017.02.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 02/02/2017] [Accepted: 02/03/2017] [Indexed: 06/06/2023]
Abstract
The life cycle assessment of several zinc oxide (ZnO) nanostructures, fabricated by a facile microwave technique, is presented. Key synthesis parameters such as annealing temperature, varied from 90°C to 220°C, and microwave power, varied from 110W to 710W, are assessed. The effect of these parameters on both the structural characteristics and the environmental sustainability of the nanostructures is examined. The nanostructures were characterized by means of X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), ultraviolet-visible spectroscopy (UV-Vis), Photoluminescence (PL) and Brunauer-Emmett-Teller (BET) analysis. Crystalline size was found to be 22.40nm at 110W microwave power, 24.83nm at 310W, and 24.01nm at 710W. Microwave power and synthesis temperature were both directly proportional to the surface area. At 110W the surface area was 10.44m2/g, at 310W 12.88m2/g, and at 710W 14.60m2/g; while it was found to be 11.64m2/g at 150°C and 18.09m2/g at 220°C. Based on these, a life cycle analysis (LCA) of the produced ZnO nanoparticles was carried out, using the ZnO surface area (1m2/g) as the functional unit. It was found that the main environmental weaknesses identified during the production process were; (a) the use of ethanol for purifying the produced nanomaterials and (b) the electricity consumption for the ZnO calcination, provided by South Africa's fossil-fuel dependent electricity source. When the effect of the key synthesis parameters on environmental sustainability was examined it was found that an increase of either microwave power (from 110 to 710W) or synthesis temperatures (from 90 to 220°C), results in higher sustainability, with the environmental footprint reduced by 27% and 41%, respectively. Through a sensitivity analysis, it was observed that an electricity mix based on renewable energy could improve the environmental sustainability of the nanoparticles by 25%.
Collapse
Affiliation(s)
- D Papadaki
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH), 100, N. Plastira str, Vassilika Vouton, GR-70013 Heraklion, Crete, Greece; School of Environmental Engineering, Technical University of Crete, GR-73100 Chania, Greece; DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, Pretoria 0001, South Africa.
| | - S Foteinis
- School of Environmental Engineering, Technical University of Crete, GR-73100 Chania, Greece
| | - G H Mhlongo
- DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, Pretoria 0001, South Africa
| | - S S Nkosi
- University of Zululand, Department of Physics and Engineering, Private Bag X1001, Kwadlangezwa, 3886, South Africa
| | - D E Motaung
- DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, Pretoria 0001, South Africa
| | - S S Ray
- DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, Pretoria 0001, South Africa
| | - T Tsoutsos
- School of Environmental Engineering, Technical University of Crete, GR-73100 Chania, Greece
| | - G Kiriakidis
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH), 100, N. Plastira str, Vassilika Vouton, GR-70013 Heraklion, Crete, Greece; Physics Department, University of Crete, Vassilika Vouton, GR-71110 Heraklion, Crete, Greece
| |
Collapse
|
32
|
Nguyen NC, Chen SS, Weng YT, Thi Nguyen H, Ray SS, Li CW, Yan B, Wang J. Iodide recovery from thin film transistor liquid crystal display plants by using potassium hydroxide - driven forward osmosis. J Memb Sci 2016. [DOI: 10.1016/j.memsci.2016.07.062] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
33
|
Nguyen NC, Nguyen HT, Ho ST, Chen SS, Ngo HH, Guo W, Ray SS, Hsu HT. Exploring high charge of phosphate as new draw solute in a forward osmosis-membrane distillation hybrid system for concentrating high-nutrient sludge. Sci Total Environ 2016; 557-558:44-50. [PMID: 26994792 DOI: 10.1016/j.scitotenv.2016.03.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/04/2016] [Accepted: 03/04/2016] [Indexed: 06/05/2023]
Abstract
For the first time, a high charge of phosphate was used as the draw solute in a forward osmosis-membrane distillation (FO-MD) hybrid system for concentrating high-nutrient sludge. A high water flux (12.5L/m(2)h) and a low reverse salt flux (0.84g/m(2)) were simultaneously achieved at pH9 by using 0.1M Na3PO4 as the draw solute and deionized water as the feed solution in the FO process. The specific reverse salt flux of 0.1M Na3PO4 (Js/Jw=0.07g/L) was considerably less than that of 0.1M NaCl (Js/Jw=0.37g/L) because the complexion between Na(+) and HPO4(2-) at pH9 led to the reduction of free Na(+) ions, which subsequently reduced the reverse salt diffusion substantially. Moreover, for a feed solution with an initial sludge concentration of 3500mg/L, the sludge concentration could be concentrated to 19,800 and 22,000mg/L in the pressure-retarded osmosis (PRO) and FO membrane orientations, respectively, after 15h of operation. Four types of MD membranes were selected for draw solution recovery; of these, a polytetrafluoroethylene membrane with a pore size of 0.45μm was the most effective in achieving a high water flux (10.28L/m(2)h) and high salt rejection (approximately 100%) in a diluted Na3PO4 draw solution.
Collapse
Affiliation(s)
- Nguyen Cong Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC; Faculty of Environment and Natural Resources, DaLat University, Viet Nam
| | - Hau Thi Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC; Faculty of Environment and Natural Resources, DaLat University, Viet Nam
| | - Su-Thing Ho
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC.
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW 2007, Australia.
| | - Wenshan Guo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC
| | - Hung-Te Hsu
- Department of Environmental Engineering, Chung Yuan Christian University, Chung Li 32023, Taiwan, ROC
| |
Collapse
|
34
|
Nguyen NC, Nguyen HT, Chen SS, Ngo HH, Guo W, Chan WH, Ray SS, Li CW, Hsu HT. A novel osmosis membrane bioreactor-membrane distillation hybrid system for wastewater treatment and reuse. Bioresour Technol 2016; 209:8-15. [PMID: 26946435 DOI: 10.1016/j.biortech.2016.02.102] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 02/21/2016] [Accepted: 02/22/2016] [Indexed: 06/05/2023]
Abstract
A novel approach was designed to simultaneously enhance nutrient removal and reduce membrane fouling for wastewater treatment using an attached growth biofilm (AGB) integrated with an osmosis membrane bioreactor (OsMBR) system for the first time. In this study, a highly charged organic compound (HEDTA(3-)) was employed as a novel draw solution in the AGB-OsMBR system to obtain a low reverse salt flux, maintain a healthy environment for the microorganisms. The AGB-OsMBR system achieved a stable water flux of 3.62L/m(2)h, high nutrient removal of 99% and less fouling during a 60-day operation. Furthermore, the high salinity of diluted draw solution could be effectively recovered by membrane distillation (MD) process with salt rejection of 99.7%. The diluted draw solution was re-concentrated to its initial status (56.1mS/cm) at recovery of 9.8% after 6h. The work demonstrated that novel multi-barrier systems could produce high quality potable water from impaired streams.
Collapse
Affiliation(s)
- Nguyen Cong Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC; Faculty of Environment and Natural Resources, Da Lat University, Viet Nam
| | - Hau Thi Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC; Faculty of Environment and Natural Resources, Da Lat University, Viet Nam
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC.
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Wenshan Guo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Wen Hao Chan
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd, Taipei 106, Taiwan, ROC
| | - Chi-Wang Li
- Department of Water Resources and Environmental Engineering, TamKang University, 151 Yingzhuan Road, Tamsui District, New Taipei City 25137, Taiwan, ROC
| | - Hung-Te Hsu
- Department of Environmental Engineering, Chung Yuan Christian University, Chung Li 32023, Taiwan, ROC
| |
Collapse
|
35
|
Nguyen NC, Chen SS, Nguyen HT, Ray SS, Ngo HH, Guo W, Lin PH. Innovative sponge-based moving bed-osmotic membrane bioreactor hybrid system using a new class of draw solution for municipal wastewater treatment. Water Res 2016; 91:305-313. [PMID: 26803266 DOI: 10.1016/j.watres.2016.01.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [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: 10/23/2015] [Revised: 01/08/2016] [Accepted: 01/12/2016] [Indexed: 06/05/2023]
Abstract
For the first time, an innovative concept of combining sponge-based moving bed (SMB) and an osmotic membrane bioreactor (OsMBR), known as the SMB-OsMBR hybrid system, were investigated using Triton X-114 surfactant coupled with MgCl2 salt as the draw solution. Compared to traditional activated sludge OsMBR, the SMB-OsMBR system was able to remove more nutrients due to the thick-biofilm layer on sponge carriers. Subsequently less membrane fouling was observed during the wastewater treatment process. A water flux of 11.38 L/(m(2) h) and a negligible reverse salt flux were documented when deionized water served as the feed solution and a mixture of 1.5 M MgCl2 and 1.5 mM Triton X-114 was used as the draw solution. The SMB-OsMBR hybrid system indicated that a stable water flux of 10.5 L/(m(2) h) and low salt accumulation were achieved in a 90-day operation. Moreover, the nutrient removal efficiency of the proposed system was close to 100%, confirming the effectiveness of simultaneous nitrification and denitrification in the biofilm layer on sponge carriers. The overall performance of the SMB-OsMBR hybrid system using MgCl2 coupled with Triton X-114 as the draw solution demonstrates its potential application in wastewater treatment.
Collapse
Affiliation(s)
- Nguyen Cong Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei 106, Taiwan, ROC
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei 106, Taiwan, ROC.
| | - Hau Thi Nguyen
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei 106, Taiwan, ROC
| | - Saikat Sinha Ray
- Institute of Environmental Engineering and Management, National Taipei University of Technology, No.1, Sec. 3, Chung -Hsiao E. Rd, Taipei 106, Taiwan, ROC
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW2007, Australia.
| | - Wenshan Guo
- School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, Broadway, NSW2007, Australia
| | - Po-Hsun Lin
- Department of Safety, Health and Environmental Engineering, Ming Chi University of Technology, Taiwan, ROC
| |
Collapse
|
36
|
Ray SS, Chen SS, Li CW, Nguyen NC, Nguyen HT. A comprehensive review: electrospinning technique for fabrication and surface modification of membranes for water treatment application. RSC Adv 2016. [DOI: 10.1039/c6ra14952a] [Citation(s) in RCA: 198] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The review paper discusses the surface modification and fabrication of electrospun nanofibers for wastewater treatment.
Collapse
Affiliation(s)
- Saikat Sinha Ray
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Shiao-Shing Chen
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
| | - Chi-Wang Li
- Department of Water Resources and Environmental Engineering
- TamKang University
- New Taipei City 25137
- Republic of China
| | - Nguyen Cong Nguyen
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
- Faculty of Environment and Natural Resources
| | - Hau Thi Nguyen
- Institute of Environmental Engineering and Management
- National Taipei University of Technology
- Taipei-10608
- Taiwan
- Faculty of Environment and Natural Resources
| |
Collapse
|
37
|
Ray SS, Asthana S, Agarwal T, Singothu S, Samal A, Banerjee I, Pal K, Pramanik K. Molecular docking and interactions of pueraria tuberosa with vascular endothelial growth factor receptors. Indian J Pharm Sci 2015; 77:439-45. [PMID: 26664060 PMCID: PMC4649782 DOI: 10.4103/0250-474x.164780] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Pueraria tuberosa is known for its therapeutic potentials in cardiovascular disorders, but its effect in angiogenesis has not been studied so far. In this study, a computational approach has been applied to elucidate the role of the phytochemicals in inhibition of angiogenesis through modulation of vascular endothelial growth factor receptors: Vascular endothelial growth factor receptor-1 and vascular endothelial growth factor receptor-2, major factors responsible for angiogenesis. Metabolite structures retrieved from PubChem and KNApSAcK – 3D databases, were docked using AutoDock4.2 tool. Hydrogen bond and molecular docking, absorption, distribution, metabolism and excretion and toxicity predictions were carried out using UCSF Chimera, LigPlot+ and PreADMET server, respectively. From the docking analysis, it was observed that puerarone and tuberostan had significant binding affinity for the intracellular kinase domain of vascular endothelial growth factor receptors-1 and vascular endothelial growth factor receptor-2 respectively. It is important to mention that both the phytochemicals shared similar interaction profile as that of standard inhibitors of vascular endothelial growth factor receptors. Also, both puerarone and tuberostan interacted with Lys861/Lys868 (adenosine 5’-triphosphate binding site of vascular endothelial growth factor receptors-1/vascular endothelial growth factor receptors-2), thus providing a clue that they may enforce their inhibitory effect by blocking the adenosine 5’-triphosphate binding domain of vascular endothelial growth factor receptors. Moreover, these molecules exhibited good drug-likeness, absorption, distribution, metabolism and excretion properties without any carcinogenic and toxic effects. The interaction pattern of the puerarone and tuberostan may provide a hint for a novel drug design for vascular endothelial growth factor tyrosine kinase receptors with better specificity to treat angiogenic disorders.
Collapse
|
38
|
Aderibigbe BA, Sadiku ER, Ray SS, Mbianda XY, Fotsing MC, Jayaramudu J, Owonubi SJ. Synthesis, characterization and the release kinetics of antiproliferative agents from polyamidoamine conjugates. J Microencapsul 2015; 32:432-442. [PMID: 26268953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Polyamidoamine conjugates containing curcumin and bisphosphonate were synthesized via a one-pot aqueous phase Michael addition reaction. In the design of the conjugate, bisphosphonate formed an integral part of the polymer carrier backbone. Curcumin was incorporated onto the polyamidoamine backbone via piperazine linker. The conjugates were characterized by Fourier transform spectroscopy, energy-dispersive X-ray analysis, atomic force spectroscopy and nuclear magnetic resonance spectroscopy and it confirmed the successful incorporation of the antiproliferative agents onto the carriers. The weight percentage incorporation of bisphosphonate to the carriers was found to be between 2.56% and 3.34%. The in vitro release studies of curcumin from the polyamidoamine conjugate were performed in dialysis bag at selected pH values. The release of curcumin was significantly slower at pH 7.4 when compared to pH 5.8. The release profiles indicate that the conjugates are more stable at pH 7.4 and are potential sustained drug-delivery systems for combination therapy.
Collapse
Affiliation(s)
- B A Aderibigbe
- Department of Chemistry, University of Fort Hare , Eastern Cape , South Africa
| | | | | | | | | | | | | |
Collapse
|
39
|
Motaung DE, Mhlongo GH, Nkosi SS, Malgas GF, Mwakikunga BW, Coetsee E, Swart HC, Abdallah HMI, Moyo T, Ray SS. Shape-selective dependence of room temperature ferromagnetism induced by hierarchical ZnO nanostructures. ACS Appl Mater Interfaces 2014; 6:8981-95. [PMID: 24896749 DOI: 10.1021/am501911y] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We report on the room temperature ferromagnetism of various highly crystalline zinc oxide (ZnO) nanostructures, such as hexagonally shaped nanorods, nanocups, nanosamoosas, nanoplatelets, and hierarchical nano "flower-like" structures. These materials were synthesized in a shape-selective manner using simple microwave assisted hydrothermal synthesis. Thermogravimetric analyses demonstrated the as-synthesized ZnO nanostructures to be stable and of high purity. Structural analyses showed that the ZnO nanostructures are polycrystalline and wurtzite in structure, without any secondary phases. Combination of electron paramagnetic resonance, photoluminescence, and X-ray photoelectron spectroscopy studies revealed that the zinc vacancies (VZn) and singly ionized oxygen vacancies (VO(+)) located mainly on the ZnO surface are the primary defects in ZnO structures. A direct link between ferromagnetism and the relative occupancy of the VZn and VO(+) was established, suggesting that both VZn and VO(+) on the ZnO surface plays a vital role in modulating ferromagnetic behavior. An intense structure- and shape-dependent ferromagnetic signal with an effective g-value of >2.0 and a sextet hyperfine structure was shown. Moreover, a novel low field microwave absorption signal was observed and found to increase with an increase in microwave power and temperature.
Collapse
Affiliation(s)
- D E Motaung
- DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research , P.O. Box 395, Pretoria 0001, South Africa
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Ray SS, Das D, Ghosh T, Ghosh AK. The levels of zinc and molybdenum in hair and food grain in areas of high and low incidence of esophageal cancer: a comparative study. Glob J Health Sci 2012; 4:168-75. [PMID: 22980353 PMCID: PMC4776934 DOI: 10.5539/gjhs.v4n4p168] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 06/13/2012] [Accepted: 06/05/2012] [Indexed: 12/03/2022] Open
Abstract
The outcome of different studies on the role of Zn & Mo in esophageal cancer (EC) is conflicting. Here, the levels of those elements in hair as well as food grain of two different ethnic populations across two continents have been studied to explore their role in EC. Two different ethnic populations are taken from (i) Eastern Cape, South Africa (RSA), an area of very high incidence of EC and (ii) West Bengal, India, an area of low incidence of that disease. Each ethnic population is divided into two groups: case and control (n=30 for all groups). Hair samples from all groups and food grains from RSA and India are analyzed for Zn & Mo content. This study shows a strong correlation between reduced levels of those elements in hair and the development of EC in RSA (both Zn & Mo: p<0.0001), though it is only suggestive in Indian context (both Zn & Mo: p≥0.05). Interestingly, control group of RSA shows significantly reduced level of those elements in hair even with respect to Indian case group (Zn: p<0.001 & Mo: p<0.00001). Food grain from RSA has significantly reduced level of those elements with respect to India (both Zn & Mo: p<0.0001). This deficiency of Zn & Mo in food grains can be correlated to the deficiency of those elements in hair of RSA population. The deficiency of Zn & Mo can be correlated to the development of EC.
Collapse
Affiliation(s)
- S S Ray
- Department of Radiation Oncology, CCWH & RI, Calcutta, India
| | | | | | | |
Collapse
|
41
|
Ray SS, Singh SK, Balaram P. An electrospray ionization mass spectrometry investigation of 1-anilino-8-naphthalene-sulfonate (ANS) binding to proteins. J Am Soc Mass Spectrom 2001; 12:428-438. [PMID: 11322189 DOI: 10.1016/s1044-0305(01)00206-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The binding of 1-anilino-8-naphthalene-sulfonic acid (ANS) to various globular proteins at acidic pH has been investigated by electrospray ionization mass spectrometry (ESI-MS). Maximal ANS binding is observed in the pH range 3-5. As many as seven species of dye-bound complexes are detected for myoglobin. Similar studies were carried out with cytochrome c, carbonic anhydrase, triosephosphate isomerase, lysozyme, alpha-lactalbumin, and bovine pancreatic trypsin inhibitor (BPTI). Strong ANS binding was observed wherever molten globule states were postulated in solution. ANS binding is not observed for lysozyme and BPTI, which have tightly folded structures in the native form. Alpha-lactalbumin, which is structurally related to lysozyme but forms a molten globule at acidic pH, exhibited ANS binding. Reduction of disulfide bonds in these proteins leads to the detection of ANS binding even at neutral pH. Binding was suppressed at very low pH (<2.5), presumably due to neutralization of the charge on the sulfonate moiety. The distribution of the relative intensities of the protein bound ANS species varies with the charge state, suggesting heterogeneity of gas phase conformations. The binding strength of these complexes was qualitatively estimated by dissociating them using enhanced nozzle skimmer potentials. The skimmer voltages also affected the lower and higher charge states of these complexes in a different manner.
Collapse
Affiliation(s)
- S S Ray
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore
| | | | | |
Collapse
|
42
|
Abstract
BACKGROUND The limited proteolytic cleavage of proteins can result in distinct polypeptides that remain noncovalently associated so that the structural and biochemical properties of the 'nicked' protein are virtually indistinguishable from those of the native protein. The remarkable observation that rabbit muscle triosephosphate isomerase (TIM) can be multiply nicked by subtilisin and efficiently religated in the presence of an organic solvent formed the stimulus for our study on a homologous system, Plasmodium falciparum triosephosphate isomerase (PfTIM). RESULTS The subtilisin nicked form of PfTIM was prepared by limited proteolysis using subtilisin and the major fragments identified using electrospray ionization mass spectrometry. The order of susceptibility of the peptide bonds in the protein was also determined. The structure of the nicked form of TIM was investigated using circular dichroism, fluorescence and gel filtration. The nicked enzyme exhibited remarkable stability to denaturants, although significant differences were observed with the wild-type enzyme. Efficient religation could be achieved by addition of an organic cosolvent, such as acetonitrile, in the presence of subtilisin. Religation was also demonstrated after dissociation of the proteolytic fragments in guanidinium chloride, followed by reassembly after removal of the denaturant. CONCLUSIONS The eight-stranded beta8/alpha8 barrel is a robust, widely used protein structural motif. This study demonstrates that the TIM barrel can withstand several nicks in the polypeptide backbone with a limited effect on its structure and stability.
Collapse
Affiliation(s)
- S S Ray
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, India
| | | | | |
Collapse
|
43
|
Velanker SS, Gokhale RS, Ray SS, Gopal B, Parthasarathy S, Santi DV, Balaram P, Murthy MR. Disulfide engineering at the dimer interface of Lactobacillus casei thymidylate synthase: crystal structure of the T155C/E188C/C244T mutant. Protein Sci 1999; 8:930-3. [PMID: 10211840 PMCID: PMC2144305 DOI: 10.1110/ps.8.4.930] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The crystal structure of a covalently cross-linked Lactobacillus casei thymidylate synthase has been determined at 2.8 A resolution. The sites for mutation to achieve the bis-disulfide linked dimer were identified using the disulfide modeling program MODIP. The mutant so obtained was found to be remarkably thermostable. This increase in stability has been reasoned to be entirely a consequence of the covalent gluing between the two subunits.
Collapse
Affiliation(s)
- S S Velanker
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Gokhale RS, Ray SS, Balaram H, Balaram P. Unfolding of Plasmodium falciparum triosephosphate isomerase in urea and guanidinium chloride: evidence for a novel disulfide exchange reaction in a covalently cross-linked mutant. Biochemistry 1999; 38:423-31. [PMID: 9890925 DOI: 10.1021/bi981087s] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The conformational stability of Plasmodium falciparum triosephosphate isomerase (TIMWT) enzyme has been investigated in urea and guanidinium chloride (GdmCl) solutions using circular dichroism, fluorescence, and size-exclusion chromatography. The dimeric enzyme is remarkably stable in urea solutions. It retains considerable secondary, tertiary, and quaternary structure even in 8 M urea. In contrast, the unfolding transition is complete by 2.4 M GdmCl. Although the secondary as well as the tertiary interactions melt before the perturbation of the quaternary structure, these studies imply that the dissociation of the dimer into monomers ultimately leads to the collapse of the structure, suggesting that the interfacial interactions play a major role in determining multimeric protein stability. The Cm(urea)/Cm(GdmCl) ratio (where Cm is the concentration of the denaturant required at the transition midpoint) is unusually high for triosephosphate isomerase as compared to other monomeric and dimeric proteins. A disulfide cross-linked mutant protein (Y74C) engineered to form two disulfide cross-links across the interface (13-74') and (13'-74) is dramatically destablized in urea. The unfolding transition is complete by 6 M urea and involves a novel mechanism of dimer dissociation through intramolecular thiol-disulfide exchange.
Collapse
Affiliation(s)
- R S Gokhale
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore
| | | | | | | |
Collapse
|
45
|
Gopal B, Ray SS, Gokhale RS, Balaram H, Murthy MR, Balaram P. Cavity-creating mutation at the dimer interface of Plasmodium falciparum triosephosphate isomerase: restoration of stability by disulfide cross-linking of subunits. Biochemistry 1999; 38:478-86. [PMID: 9890931 DOI: 10.1021/bi981495w] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Disulfide engineering across subunit interfaces provides a means of inhibiting dissociation during unfolding of multimeric enzymes. Two symmetry-related intersubunit disulfide bridges were introduced across the interface of the dimeric enzyme triosephosphate isomerase from Plasmodium falciparum. This was achieved by mutating a tyrosine residue at position 74 at the subunit interface to a cysteine, thereby enabling it to form a covalent cross-link with a pre-existing cysteine at position 13 of the other subunit. The wild-type enzyme (TIMWT) and the oxidized (Y74Cox) and reduced (Y74Cred) forms of the mutant have similar enzymatic activity, absorption, and fluorescence spectra. All three proteins have similar far-UV CD spectra. The Y74Cred shows a distinct loss of near-UV CD. Thermal precipitation studies demonstrate that TIMWT and Y74Cox have very similar Tm values (Tm approximately 60 degreesC) whereas Y74Cred is surprisingly labile (Tm approximately 38 degreesC). The Y74C mutant results in the creation of a large cavity (approximately 100 A3) at the dimer interface. The crystal structure for the oxidized form of Y74C mutant, crystallized in the presence of low concentrations of dithiothreitol, reveals an asymmetric dimer containing a disulfide bridge at one site and a reduced dithiol cysteine at the other. The crystal structure of the mutant offers insights into the destabilization effects of the interfacial cavities and the role of disulfide tethering in restoring protein stability.
Collapse
Affiliation(s)
- B Gopal
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore
| | | | | | | | | | | |
Collapse
|
46
|
Ray SS, Gangopadhyay SS, Pande G, Samuelson J, Lohia A. Primary structure of Entamoeba histolytica gamma-tubulin and localisation of amoebic microtubule organising centres. Mol Biochem Parasitol 1997; 90:331-6. [PMID: 9497056 DOI: 10.1016/s0166-6851(97)00157-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- S S Ray
- Department of Biochemistry, Bose Institute, Calcutta, India
| | | | | | | | | |
Collapse
|
47
|
Gangopadhyay SS, Ray SS, Kennady K, Pande G, Lohia A. Heterogeneity of DNA content and expression of cell cycle genes in axenically growing Entamoeba histolytica HM1:IMSS clone A. Mol Biochem Parasitol 1997; 90:9-20. [PMID: 9497028 DOI: 10.1016/s0166-6851(97)00156-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The cell division cycle of Entamoeba histolytica was studied using multi-parametric flow cytometry in asynchronous and partially synchronised cells. Dynamic changes in the DNA synthesis and DNA content of axenically growing trophozoites were observed by using 5-bromo-2'-deoxyuridine (BrdU) uptake and DNA specific fluorochromes. It was observed that DNA synthesis in these cells continues beyond the typical S-phase stop point when DNA duplication is complete. Asynchronously growing E. histolytica cells could be synchronised by serum starvation followed by serum re-addition. BrdU incorporation in synchronised cells showed that cell synchrony is maintained for at least one generation time, in which the G1 phase lasts for 2-3 h and the S-phase lasts for 5-6 h. Analysis of our results revealed that E. histolytica trophozoites, growing in axenic medium, are made up of a heterogenous population of euploid and polyploid cells. The number of polyploid cells increases with age of the cells in culture. Expression of putative cell cycle and signal transduction markers was studied using specific antibodies and changes in their expression levels have been correlated with changes in the DNA content. Based upon our results we could identify G1, S and G2 phases of the cell cycle of E. histolytica and also predict the mechanism underlying the generation of polyploidy in these cells, which may have significant effects on its biology and pathogenesis.
Collapse
|
48
|
Abstract
We have isolated homologs of the mini chromosome maintenance (MCM) gene family from the parasitic protozoan Entamoeba histolytica. The full length genomic and cDNA clones for the Eh MCM3 gene have been characterised. The Eh MCM3 gene is much smaller than the Saccharomyces cerevisiae MCM3 gene and other eukaryotic homologs of the MCM3/P1 family. The predicted Eh Mcm3 protein was 597 amino acids long and showed 37 and 46% positional identity with the Sc Mcm3 and the mouse P1 homologs respectively. While proceeding along the chromosome from the Eh MCM3 gene, we have identified a homolog (Eh PAK) of the murine p21 activated kinase (Rn KPAK), or S. cerevisiae STE20. Eh PAK lies 126 bp upstream of the Eh MCM3 gene. The predicted Eh p21 activated kinase protein was 459 amino-acids long and showed 33% positional identity with the murine p21 activated kinase and its yeast homolog Ste20. Analysis of cDNA and genomic sequences shows that the 3' untranslated region (UTR) of the Eh PAK mRNA and the 5' UTR of the Eh MCM3 mRNA are transcribed from a common 40 bp genomic segment. This is the first report of an amoeba gene being physically linked to a second gene such that their transcripts are overlapping and there is no non-transcribed intergenic region between the two genes. Primer extension studies have confirmed that unlike most E. histolytica genes, which have short 5' UTRs, the Eh MCM3 mRNA has a 126 bp long 5' UTR and the Eh PAK mRNA has a 265 bp long 5' UTR.
Collapse
|
49
|
Subbayya IN, Ray SS, Balaram P, Balaram H. Metabolic enzymes as potential drug targets in Plasmodium falciparum. Indian J Med Res 1997; 106:79-94. [PMID: 9291679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Plasmodium falciparum causes the most severe form of malaria that is fatal in many cases. Emergence of drug resistant strains of P. falciparum requires that new drug targets be identified. This review considers in detail enzymes of the glycolytic pathway, purine salvage pathway, pyrimidine biosynthesis and proteases involved in catabolism of haemoglobin. Structural features of P. falciparum triosephosphate isomerase which could be exploited for parasite specific drug development have been highlighted. Utility of P. falciparum hypoxanthine-guanine-phosphoribosyltransferase, adenylosuccinate synthase, dihydroorotate dehydrogenase, thymidylate synthase-dihydrofolate reductase, cysteine and aspartic proteases have been elaborated in detail. The review also briefly touches upon other potential targets in P. falciparum.
Collapse
Affiliation(s)
- I N Subbayya
- Molecular Biophysics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore
| | | | | | | |
Collapse
|
50
|
Velanker SS, Ray SS, Gokhale RS, Suma S, Balaram H, Balaram P, Murthy MR. Triosephosphate isomerase from Plasmodium falciparum: the crystal structure provides insights into antimalarial drug design. Structure 1997; 5:751-61. [PMID: 9261072 DOI: 10.1016/s0969-2126(97)00230-x] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Malaria caused by the parasite Plasmodium falciparum is a major public health concern. The parasite lacks a functional tricarboxylic acid cycle, making glycolysis its sole energy source. Although parasite enzymes have been considered as potential antimalarial drug targets, little is known about their structural biology. Here we report the crystal structure of triosephosphate isomerase (TIM) from P. falciparum at 2.2 A resolution. RESULTS The crystal structure of P. falciparum TIM (PfTIM), expressed in Escherichia coli, was determined by the molecular replacement method using the structure of trypanosomal TIM as the starting model. Comparison of the PfTIM structure with other TIM structures, particularly human TIM, revealed several differences. In most TIMs the residue at position 183 is a glutamate but in PfTIM it is a leucine. This leucine residue is completely exposed and together with the surrounding positively charged patch, may be responsible for binding TIM to the erythrocyte membrane. Another interesting feature is the occurrence of a cysteine residue at the dimer interface of PfTIM (Cys13), in contrast to human TIM where this residue is a methionine. Finally, residue 96 of human TIM (Ser96), which occurs near the active site, has been replaced by phenylalanine in PfTIM. CONCLUSIONS Although the human and Plasmodium enzymes share 42% amino acid sequence identity, several key differences suggest that PfTIM may turn out to be a potential drug target. We have identified a region which may be responsible for binding PfTIM to cytoskeletal elements or the band 3 protein of erythrocytes; attachment to the erythrocyte membrane may subsequently lead to the extracellular exposure of parts of the protein. This feature may be important in view of a recent report that patients suffering from P. falciparum malaria mount an antibody response to TIM leading to prolonged hemolysis. A second approach to drug design may be provided by the mutation of the largely conserved residue (Ser96) to phenylalanine in PfTIM. This difference may be of importance in designing specific active-site inhibitors against the enzyme. Finally, specific inhibition of PfTIM subunit assembly might be possible by targeting Cys13 at the dimer interface. The crystal structure of PfTIM provides a framework for new therapeutic leads.
Collapse
Affiliation(s)
- S S Velanker
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | | | | | | | | | | | | |
Collapse
|