101
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Panáček A, Smékalová M, Kilianová M, Prucek R, Bogdanová K, Večeřová R, Kolář M, Havrdová M, Płaza GA, Chojniak J, Zbořil R, Kvítek L. Strong and Nonspecific Synergistic Antibacterial Efficiency of Antibiotics Combined with Silver Nanoparticles at Very Low Concentrations Showing No Cytotoxic Effect. Molecules 2015; 21:E26. [PMID: 26729075 PMCID: PMC6273824 DOI: 10.3390/molecules21010026] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 12/15/2015] [Accepted: 12/17/2015] [Indexed: 01/05/2023] Open
Abstract
The resistance of bacteria towards traditional antibiotics currently constitutes one of the most important health care issues with serious negative impacts in practice. Overcoming this issue can be achieved by using antibacterial agents with multimode antibacterial action. Silver nano-particles (AgNPs) are one of the well-known antibacterial substances showing such multimode antibacterial action. Therefore, AgNPs are suitable candidates for use in combinations with traditional antibiotics in order to improve their antibacterial action. In this work, a systematic study quantifying the synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus was performed. Employing the microdilution method as more suitable and reliable than the disc diffusion method, strong synergistic effects were shown for all tested antibiotics combined with AgNPs at very low concentrations of both antibiotics and AgNPs. No trends were observed for synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs, indicating non-specific synergistic effects. Moreover, a very low amount of silver is needed for effective antibacterial action of the antibiotics, which represents an important finding for potential medical applications due to the negligible cytotoxic effect of AgNPs towards human cells at these concentration levels.
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Affiliation(s)
- Aleš Panáček
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University in Olomouc, 17 listopadu 12, 771 46 Olomouc, Czech Republic.
| | - Monika Smékalová
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University in Olomouc, 17 listopadu 12, 771 46 Olomouc, Czech Republic.
| | - Martina Kilianová
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University in Olomouc, 17 listopadu 12, 771 46 Olomouc, Czech Republic.
| | - Robert Prucek
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University in Olomouc, 17 listopadu 12, 771 46 Olomouc, Czech Republic.
| | - Kateřina Bogdanová
- Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University in Olomouc, Hněvotínská 5, 775 15 Olomouc, Czech Republic.
| | - Renata Večeřová
- Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University in Olomouc, Hněvotínská 5, 775 15 Olomouc, Czech Republic.
| | - Milan Kolář
- Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University in Olomouc, Hněvotínská 5, 775 15 Olomouc, Czech Republic.
| | - Markéta Havrdová
- Regional Centre of Advanced Technologies and Materials, Department of Experimental Physics and Physical Chemistry, faculty of Science, Palacký University in Olomouc, 17 listopadu 12, 771 46 Olomouc, Czech Republic.
| | - Grażyna Anna Płaza
- Department of Environmental Microbiology, Institute for Ecology of Industrial Areas, Kossutha 6, 40-844 Katowice, Poland.
| | - Joanna Chojniak
- Department of Environmental Microbiology, Institute for Ecology of Industrial Areas, Kossutha 6, 40-844 Katowice, Poland.
| | - Radek Zbořil
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University in Olomouc, 17 listopadu 12, 771 46 Olomouc, Czech Republic.
| | - Libor Kvítek
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacký University in Olomouc, 17 listopadu 12, 771 46 Olomouc, Czech Republic.
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102
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Cui L, Chen P, Zhang B, Zhang D, Li J, Martin FL, Zhang K. Interrogating chemical variation via layer-by-layer SERS during biofouling and cleaning of nanofiltration membranes with further investigations into cleaning efficiency. WATER RESEARCH 2015; 87:282-291. [PMID: 26433006 DOI: 10.1016/j.watres.2015.09.037] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/18/2015] [Accepted: 09/21/2015] [Indexed: 06/05/2023]
Abstract
Periodic chemical cleaning is an essential step to maintain nanofiltration (NF) membrane performance and mitigate biofouling, a major impediment in high-quality water reclamation from wastewater effluent. To target the important issue of how to clean and control biofouling more efficiently, this study developed surface-enhanced Raman spectroscopy (SERS) as a layer-by-layer tool to interrogate the chemical variations during both biofouling and cleaning processes. The fact that SERS only reveals information on the surface composition of biofouling directly exposed to cleaning reagents makes it ideal for evaluating cleaning processes and efficiency. SERS features were highly distinct and consistent with different biofouling stages (bacterial adhesion, rapid growth, mature and aged biofilm). Cleaning was performed on two levels of biofouling after 18 h (rapid growth of biofilm) and 48 h (aged biofilm) development. An opposing profile of SERS bands between biofouling and cleaning was observed and this suggests a layer-by-layer cleaning mode. In addition, further dynamic biochemical and infrastructural changes were demonstrated to occur in the more severe 48-h biofouling, resulting in the easier removal of sessile cells from the NF membrane. Biofouling substance-dependent cleaning efficiency was also evaluated using the surfactant sodium dodecyl sulfate (SDS). SDS appeared more efficient in cleaning lipid than polysaccharide and DNA. Protein and DNA were the predominant residual substances (irreversible fouling) on NF membrane leading to permanent flux loss. The chemical information revealed by layer-by-layer SERS will lend new insights into the optimization of cleaning reagents and protocols for practical membrane processes.
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Affiliation(s)
- Li Cui
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| | - Pengyu Chen
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Bifeng Zhang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Dayi Zhang
- Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom
| | - Junyi Li
- Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom
| | - Francis L Martin
- Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom
| | - Kaisong Zhang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
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103
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Hartley JS, Hlaing MM, Seniutinas G, Juodkazis S, Stoddart PR. Black silicon as a platform for bacterial detection. BIOMICROFLUIDICS 2015; 9:061101. [PMID: 26576207 PMCID: PMC4636504 DOI: 10.1063/1.4934966] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 10/20/2015] [Indexed: 05/26/2023]
Abstract
Surface-enhanced Raman scattering (SERS) shows promise for identifying single bacteria, but the short range nature of the effect makes it most sensitive to the cell membrane, which provides limited information for species-level identification. Here, we show that a substrate based on black silicon can be used to impale bacteria on nanoscale SERS-active spikes, thereby producing spectra that convey information about the internal composition of the bacterial capsule. This approach holds great potential for the development of microfluidic devices for the removal and identification of single bacteria in important clinical diagnostics and environmental monitoring applications.
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Affiliation(s)
- Jennifer S Hartley
- Faculty of Science, Engineering and Technology, Swinburne University of Technology , Hawthorn, Victoria 3122, Australia
| | - M Myintzu Hlaing
- Faculty of Science, Engineering and Technology, Swinburne University of Technology , Hawthorn, Victoria 3122, Australia
| | | | | | - Paul R Stoddart
- Faculty of Science, Engineering and Technology, Swinburne University of Technology , Hawthorn, Victoria 3122, Australia
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104
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Jain N, Bhargava A, Rathi M, Dilip RV, Panwar J. Removal of Protein Capping Enhances the Antibacterial Efficiency of Biosynthesized Silver Nanoparticles. PLoS One 2015; 10:e0134337. [PMID: 26226385 PMCID: PMC4520467 DOI: 10.1371/journal.pone.0134337] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Accepted: 07/08/2015] [Indexed: 11/20/2022] Open
Abstract
The present study demonstrates an economical and environmental affable approach for the synthesis of “protein-capped” silver nanoparticles in aqueous solvent system. A variety of standard techniques viz. UV-visible spectroscopy, transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) measurements were employed to characterize the shape, size and composition of nanoparticles. The synthesized nanoparticles were found to be homogenous, spherical, mono-dispersed and covered with multi-layered protein shell. In order to prepare bare silver nanoparticles, the protein shell was removed from biogenic nanoparticles as confirmed by UV-visible spectroscopy, FTIR and photoluminescence analysis. Subsequently, the antibacterial efficacy of protein-capped and bare silver nanoparticles was compared by bacterial growth rate and minimum inhibitory concentration assay. The results revealed that bare nanoparticles were more effective as compared to the protein-capped silver nanoparticles with varying antibacterial potential against the tested Gram positive and negative bacterial species. Mechanistic studies based on ROS generation and membrane damage suggested that protein-capped and bare silver nanoparticles demonstrate distinct mode of action. These findings were strengthened by the TEM imaging along with silver ion release measurements using inductively coupled plasma atomic emission spectroscopy (ICP-AES). In conclusion, our results illustrate that presence of protein shell on silver nanoparticles can decrease their bactericidal effects. These findings open new avenues for surface modifications of nanoparticles to modulate and enhance their functional properties.
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Affiliation(s)
- Navin Jain
- Centre for Biotechnology, Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333 031, India
| | - Arpit Bhargava
- Centre for Biotechnology, Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333 031, India
| | - Mohit Rathi
- Centre for Biotechnology, Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333 031, India
| | - R. Venkataramana Dilip
- Centre for Biotechnology, Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333 031, India
| | - Jitendra Panwar
- Centre for Biotechnology, Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333 031, India
- * E-mail:
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105
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Thomas R, Soumya KR, Mathew J, Radhakrishnan EK. Inhibitory effect of silver nanoparticle fabricated urinary catheter on colonization efficiency of Coagulase Negative Staphylococci. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 149:68-77. [PMID: 26048526 DOI: 10.1016/j.jphotobiol.2015.04.034] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 04/05/2015] [Accepted: 04/30/2015] [Indexed: 12/19/2022]
Abstract
Multiple antibiotic resistance and diverse mechanisms for biofilm formation make Coagulase Negative Staphylococci (CoNS) to cause infections associated with insertion of medical devices. As the infectious life style of CoNS pose difficult to treat conditions, materials with multitargeted antimicrobial effect can offer promising ways to modify the surface of devices to limit microbial growth. The broad spectrum of antimicrobial properties shown by silver nanoparticles (AgNPs) make it as an excellent candidate to act on device surface as persistent antimicrobial structures. In the current study, AgNPs assembled by soil bacteria under visible light at room temperature were analysed for its physical properties by UV-Vis spectroscopy, FTIR, SEM, HR-TEM and EDS and they also showed significant antimicrobial and antibiofilm properties against selected members of CoNS like Staphylococcus epidermidis and Staphylococcus haemolyticus. Very interestingly, further analysis on antibacterial mechanism of AgNPs showed their remarkable ability to cause disorganization of bacterial cell membrane. Further, surface engineering application of AgNPs on urinary catheter showed its excellent potential to prevent the attachment and colonization of CoNS which make result of study with significantly novel medical applications.
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Affiliation(s)
- Roshmi Thomas
- School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala 686 560, India
| | - K R Soumya
- School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala 686 560, India
| | - Jyothis Mathew
- School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala 686 560, India
| | - E K Radhakrishnan
- School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala 686 560, India.
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106
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Bao H, Yu X, Xu C, Li X, Li Z, Wei D, Liu Y. New toxicity mechanism of silver nanoparticles: promoting apoptosis and inhibiting proliferation. PLoS One 2015; 10:e0122535. [PMID: 25822182 PMCID: PMC4378976 DOI: 10.1371/journal.pone.0122535] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 02/13/2015] [Indexed: 11/18/2022] Open
Abstract
Silver nanoparticles are increasingly recognized for their utility in biological applications, especially antibacterial effects. Herein, we confirmed the antibacterial effect of silver nanoparticles on Escherichia coli using the conventional optical density (OD) and colony-forming units (CFU) method and used flow cytometry (FC), TEM and BrdU ELISA to investigate the mechanisms of this effect. From the results, we conclude that AgNPs can simultaneously induce apoptosis and inhibit new DNA synthesis in the cells in a positive concentration-dependent manner. This study presents the first induction of apoptosis in these bacteria by AgNPs in this field. Our findings may provide a new strategy for the use of silver nanoparticles in antibacterial applications.
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Affiliation(s)
- Huijing Bao
- School of Laboratory Science, Tianjin Medical University, Tianjin, China
| | - Xiaoxu Yu
- School of Laboratory Science, Tianjin Medical University, Tianjin, China
| | - Chen Xu
- The 4 Central Hospital, Tianjin, China, China
| | - Xue Li
- School of Laboratory Science, Tianjin Medical University, Tianjin, China
| | - Zhaoyang Li
- School of Materials Science and Engineering, Tianjin University, Tianjin, China
| | - Dianjun Wei
- The Department of Laboratory Science, The Second Hospital of Tianjin Medical University, Tianjin, China
- * E-mail: (YL); (DW)
| | - Yunde Liu
- School of Laboratory Science, Tianjin Medical University, Tianjin, China
- * E-mail: (YL); (DW)
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107
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Suchomel P, Kvitek L, Panacek A, Prucek R, Hrbac J, Vecerova R, Zboril R. Comparative study of antimicrobial activity of AgBr and Ag nanoparticles (NPs). PLoS One 2015; 10:e0119202. [PMID: 25781988 PMCID: PMC4363559 DOI: 10.1371/journal.pone.0119202] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 01/11/2015] [Indexed: 11/30/2022] Open
Abstract
The diverse mechanism of antimicrobial activity of Ag and AgBr nanoparticles against gram-positive and gram-negative bacteria and also against several strains of candida was explored in this study. The AgBr nanoparticles (NPs) were prepared by simple precipitation of silver nitrate by potassium bromide in the presence of stabilizing polymers. The used polymers (PEG, PVP, PVA, and HEC) influence significantly the size of the prepared AgBr NPs dependently on the mode of interaction of polymer with Ag+ ions. Small NPs (diameter of about 60–70 nm) were formed in the presence of the polymer with low interaction as are PEG and HEC, the polymers which interact with Ag+ strongly produce nearly two times bigger NPs (120–130 nm). The prepared AgBr NPs were transformed to Ag NPs by the reduction using NaBH4. The sizes of the produced Ag NPs followed the same trends – the smallest NPs were produced in the presence of PEG and HEC polymers. Prepared AgBr and Ag NPs dispersions were tested for their biological activity. The obtained results of antimicrobial activity of AgBr and Ag NPs are discussed in terms of possible mechanism of the action of these NPs against tested microbial strains. The AgBr NPs are more effective against gram-negative bacteria and tested yeast strains while Ag NPs show the best antibacterial action against gram-positive bacteria strains.
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Affiliation(s)
- Petr Suchomel
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University Olomouc, Czech Republic
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Czech Republic
| | - Libor Kvitek
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University Olomouc, Czech Republic
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Czech Republic
- * E-mail:
| | - Ales Panacek
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University Olomouc, Czech Republic
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Czech Republic
| | - Robert Prucek
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University Olomouc, Czech Republic
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Czech Republic
| | - Jan Hrbac
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Czech Republic
| | - Renata Vecerova
- Department of Microbiology, Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic
| | - Radek Zboril
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University Olomouc, Czech Republic
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Czech Republic
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108
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Cui L, Chen S, Zhang K. Effect of toxicity of Ag nanoparticles on SERS spectral variance of bacteria. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 137:1061-1066. [PMID: 25291503 DOI: 10.1016/j.saa.2014.08.155] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/11/2014] [Accepted: 08/31/2014] [Indexed: 06/03/2023]
Abstract
Ag nanoparticles (NPs) have been extensively utilized in surface-enhanced Raman scattering (SERS) spectroscopy for bacterial identification. However, Ag NPs are toxic to bacteria. Whether such toxicity can affect SERS features of bacteria and interfere with bacterial identification is still unknown and needed to explore. Here, by carrying out a comparative study on non-toxic Au NPs with that on toxic Ag NPs, we investigated the influence of nanoparticle concentration and incubation time on bacterial SERS spectral variance, both of which were demonstrated to be closely related to the toxicity of Ag NPs. Sensitive spectral alterations were observed on Ag NPs with increase of NPs concentration or incubation time, accompanied with an obvious decrease in number of viable bacteria. In contrast, SERS spectra and viable bacterial number on Au NPs were rather constant under the same conditions. A further analysis on spectral changes demonstrated that it was cell response (i.e. metabolic activity or death) to the toxicity of Ag NPs causing spectral variance. However, biochemical responses to the toxicity of Ag were very different in different bacteria, indicating the complex toxic mechanism of Ag NPs. Ag NPs are toxic to a great variety of organisms, including bacteria, fungi, algae, protozoa etc., therefore, this work will be helpful in guiding the future application of SERS technique in various complex biological systems.
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Affiliation(s)
- Li Cui
- Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| | - Shaode Chen
- College of Material Science & Engineering, Huaqiao University, Xiamen 361021, China
| | - Kaisong Zhang
- Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
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109
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El-Zahry MR, Mahmoud A, Refaat IH, Mohamed HA, Bohlmann H, Lendl B. Antibacterial effect of various shapes of silver nanoparticles monitored by SERS. Talanta 2015; 138:183-189. [PMID: 25863389 DOI: 10.1016/j.talanta.2015.02.022] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 02/04/2015] [Accepted: 02/11/2015] [Indexed: 11/15/2022]
Abstract
A comparative evaluation of antimicrobial effect of synthesized silver nanoparticles (AgNPs) of different shapes using different methods was performed. Spherical, triangular and hexagonal AgNPs with an average size of 40 nm were chemically prepared and characterized by transmission electron microscope (TEM) and UV-visible spectroscopy. The antimicrobial effect of these different AgNPs against the gram negative bacterium Escherichia coli (E. coli) was studied by surface enhanced Raman spectroscopy (SERS), the evaluation of growth curves and inhibition zones. SERS proved to be sensitive to monitor the changes that occurred in the bacterial cells upon interaction with AgNPs, which qualitatively compared well with the data provided by the reference methods. However, as SERS is already sensitive to initial changes in the chemistry of bacteria due to the antibacterial effect of the AgNPs, fast and detailed information is provided by SERS as opposed to the classical reference methods based on the evaluation of growth curves and inhibition zones. The results of this work also demonstrate that hexagonal AgNPs display the highest antibacterial effect when compared to other NPs shapes, with triangular AgNPs exhibiting no antibacterial effect under the adopted conditions.
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Affiliation(s)
- Marwa R El-Zahry
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/151, A-1060 Vienna, Austria; Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Assiut University, 71526 Assiut, Egypt.
| | - Amer Mahmoud
- Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Austria; Department of Plant Pathology, Faculty of Agriculture, Assiut University, 71526 Assiut, Egypt
| | - Ibrahim H Refaat
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Assiut University, 71526 Assiut, Egypt
| | - Horria A Mohamed
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Assiut University, 71526 Assiut, Egypt
| | - Holger Bohlmann
- Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Bernhard Lendl
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/151, A-1060 Vienna, Austria
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110
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Choudhury PR, Mondal P, Majumdar S. Synthesis of bentonite clay based hydroxyapatite nanocomposites cross-linked by glutaraldehyde and optimization by response surface methodology for lead removal from aqueous solution. RSC Adv 2015. [DOI: 10.1039/c5ra18490h] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The synthesis and characterization of novel BT–HAp nanocomposites is described and their adsorption of lead from aqueous solution followed by RSM optimization is demonstrated.
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Affiliation(s)
- Piyali Roy Choudhury
- Ceramic Membrane Division
- CSIR-Central Glass and Ceramic Research Institute
- Kolkata–700 032
- India
| | - Priyanka Mondal
- Ceramic Membrane Division
- CSIR-Central Glass and Ceramic Research Institute
- Kolkata–700 032
- India
| | - Swachchha Majumdar
- Ceramic Membrane Division
- CSIR-Central Glass and Ceramic Research Institute
- Kolkata–700 032
- India
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111
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Chen P, Cui L, Zhang K. Surface-enhanced Raman spectroscopy monitoring the development of dual-species biofouling on membrane surfaces. J Memb Sci 2015. [DOI: 10.1016/j.memsci.2014.09.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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112
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Wang YH, Li DF, Hong ZW, Liang JH, Han D, Zheng JF, Niu ZJ, Mao BW, Zhou XS. Conductance of alkyl-based molecules with one, two and three chains measured by electrochemical STM break junction. Electrochem commun 2014. [DOI: 10.1016/j.elecom.2014.05.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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113
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Subbalakshmi C, Nagaraj R. Characterization of Silver and Fluorescent Dyes Incorporated in Self-Assembling Peptides and Their Potential Applications in Biology. Chempluschem 2014. [DOI: 10.1002/cplu.201402077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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114
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Sun Q, Cai X, Li J, Zheng M, Chen Z, Yu CP. Green synthesis of silver nanoparticles using tea leaf extract and evaluation of their stability and antibacterial activity. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2013.12.065] [Citation(s) in RCA: 283] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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115
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Zhou XY, Wang YH, Qi HM, Zheng JF, Niu ZJ, Zhou XS. Single-molecule conductance of dipyridines binding to Ag electrodes measured by electrochemical scanning tunneling microscopy break junction. NANOSCALE RESEARCH LETTERS 2014; 9:77. [PMID: 24528610 PMCID: PMC3932803 DOI: 10.1186/1556-276x-9-77] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 02/06/2014] [Indexed: 05/30/2023]
Abstract
We have measured the conductance of three pyridyl-terminated molecules binding to Ag electrodes by using electrochemical jump-to-contact scanning tunneling microscopy break junction approach (ECSTM-BJ). Three molecules, including 4,4'-bipyridine (BPY), 1,2-di(pyridin-4-yl)ethene (BPY-EE), and 1,2-di(pyridin-4-yl)ethane (BPY-EA), contacting with Ag electrodes show three sets of conductance values, which follow the order of BPY > BPY-EE > BPY-EA. These values are smaller than those of molecules with Au electrodes, but larger than those of molecules with Cu electrodes. The difference may attribute to the different electronic coupling efficiencies between the molecules and electrodes. Moreover, the influence of the electrochemical potential on the Fermi level of electrodes is also discussed.
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Affiliation(s)
- Xiao-Yi Zhou
- Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
| | - Ya-Hao Wang
- Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
| | - Han-Mei Qi
- Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
| | - Ju-Fang Zheng
- Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
| | - Zhen-Jiang Niu
- Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
| | - Xiao-Shun Zhou
- Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
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116
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Wang K, Wu Y, Li H, Li M, Zhang D, Feng H, Fan H. Synthesis, characterization and antimicrobial activity of silver nanoparticles: Agn(NALC)m and Agn(GSHR)m. RSC Adv 2014. [DOI: 10.1039/c3ra46568c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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