451
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Chaudhari NK, Kim HC, Kim CS, Park J, Yu JS. Solvent controlled synthesis of new hematite superstructures with large coercive values. CrystEngComm 2012. [DOI: 10.1039/c1ce06444d] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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452
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Mandal SK, Kar T, Das D, Das PK. The striking influence of SWNT–COOH on self-assembled gelation. Chem Commun (Camb) 2012; 48:1814-6. [DOI: 10.1039/c2cc16567h] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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453
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Kar T, Mandal SK, Das PK. Influence of pristine SWNTs in supramolecular hydrogelation: scaffold for superior peroxidase activity of cytochrome c. Chem Commun (Camb) 2012; 48:8389-91. [DOI: 10.1039/c2cc33593j] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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454
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Song J, Kang H, Lee C, Hwang SH, Jang J. Aqueous synthesis of silver nanoparticle embedded cationic polymer nanofibers and their antibacterial activity. ACS APPLIED MATERIALS & INTERFACES 2012; 4:460-5. [PMID: 22181053 DOI: 10.1021/am201563t] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper describes the one-pot, aqueous synthesis of cationic polymer nanofibers with embedded silver nanoparticles. Poly[2-(tert-butylaminoethyl) methacrylate] (PTBAM) was used as a cationic polymer substrate to reinforce the antimicrobial activity of the embedded silver nanoparticles. Electron microscope analyses revealed that the as-synthesized nanofibers had diameters of approximately 40 nm and lengths up to about 10 μm. Additionally, silver nanoparticles of approximately 8 nm in diameter were finely embedded into the prepared nanofibers. The embedded silver nanoparticles had a lower tendency to agglomerate than colloidal silver nanoparticles of comparable size. In addition, the nanofibers with embedded silver nanoparticles exhibited excellent antibacterial performance against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. Interestingly, the prepared nanofibers exhibited enhanced bactericidal performance compared with the silver-embedded poly(methyl methacrylate) (PMMA) nanofibers, presumably because of the antibacterial properties of the PTBAM substrate.
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Affiliation(s)
- Jooyoung Song
- WCU program of Chemical Convergence for Energy and Environment (C2E2), School of Chemical and Biological Engineering, College of Engineering, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-742, Korea
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455
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Vivekanandhan S, Christensen L, Misra M, Kumar Mohanty A. Green Process for Impregnation of Silver Nanoparticles into Microcrystalline Cellulose and Their Antimicrobial Bionanocomposite Films. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/jbnb.2012.33035] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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456
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Surface-quaternized chitosan particles as an alternative and effective organic antibacterial material. Colloids Surf B Biointerfaces 2011; 92:121-9. [PMID: 22197736 DOI: 10.1016/j.colsurfb.2011.11.034] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Revised: 10/08/2011] [Accepted: 11/15/2011] [Indexed: 01/28/2023]
Abstract
Taking advantage of the large surface area that is covered with permanent positive charges of quaternary ammonium entities, this research aimed to develop environmentally friendly, organic antibacterial material from quaternized chitosan particles that may be applicable for biomedical devices, health and textile industries. The particles were formulated by ionic crosslinking of chitosan with tripolyphosphate followed by quaternization under heterogeneous conditions, via either direct methylation or reductive N-alkylation with a selected aldehyde followed by methylation. Sub-micron, spherical and positively charged quaternized chitosan particles were formed, as determined by (1)H NMR, FT-IR, PCS and TEM analysis. Antibacterial activity tests, performed by viable cell (colony) counts, suggested that all quaternized chitosan particles exhibited superior antibacterial activity against the model Gram-positive bacteria, Staphylococcus aureus, as compared to the native chitosan particles at neutral pH. Only some quaternized chitosan particles, especially those having a high charge density and bearing large alkyl substituent groups, were capable of suppressing the growth of the model Gram-negative bacteria, Escherichia coli. The inhibitory efficiency of the quaternized chitosan particles was quantified in terms of the minimum inhibitory concentration (MIC). Damaging impact of the quaternized chitosan particles on the bacteria was also qualitatively determined by microscopic observation of the bacterial morphology.
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457
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Silver–clay nanohybrid structure for effective and diffusion-controlled antimicrobial activity. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2011. [DOI: 10.1016/j.msec.2011.08.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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458
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Trzebuniak K, Zarychta B, Olijnyk V. The first silver(I) nitrate π-complexes with unsaturated organosilicons: Synthesis and structural characterization of [Ag(DADPS)xNO3] (DADPS=diallyldiphenylsilane, x=0.75; 1). J Mol Struct 2011. [DOI: 10.1016/j.molstruc.2011.09.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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459
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Synthesis of highly stable silver nanoparticles by photoreduction and their size fractionation by phase transfer method. Colloids Surf A Physicochem Eng Asp 2011. [DOI: 10.1016/j.colsurfa.2011.10.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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460
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Vidhu VK, Aromal SA, Philip D. Green synthesis of silver nanoparticles using Macrotyloma uniflorum. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 83:392-397. [PMID: 21920808 DOI: 10.1016/j.saa.2011.08.051] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 08/17/2011] [Accepted: 08/24/2011] [Indexed: 05/31/2023]
Abstract
Green synthesis of noble metal nanoparticles is a vast developing area of research. In this paper we report the green synthesis of silver nanoparticles using aqueous seed extract of Macrotyloma uniflorum. The effect of experimental parameters such as amount of extract, temperature and pH on the formation of silver nanoparticles was studied. The as prepared samples are characterized using XRD, TEM, UV-Visible and FTIR techniques. The formation of silver nanoparticles is evidenced by the appearance of signatory brown colour of the solution and UV-vis spectra. The XRD analysis shows that the silver nanoparticles are of face centered cubic structure. Well-dispersed silver nanoparticles with anisotropic morphology having size ∼12 nm are seen in TEM images. FTIR spectrum indicates the presence of different functional groups in capping the nanoparticles. The possible mechanism leading to the formation of silver nanoparticles is suggested.
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Affiliation(s)
- V K Vidhu
- Department of Physics, Mar Ivanios College, Thiruvananthapuram, India
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461
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Laboratory evaluation of botanical extracts, microbial culture filtrates and silver nanoparticles against Botrytis cinerea. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0388-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
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462
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Oei JD, Zhao WW, Chu L, DeSilva MN, Ghimire A, Rawls HR, Whang K. Antimicrobial acrylic materials with in situ generated silver nanoparticles. J Biomed Mater Res B Appl Biomater 2011; 100:409-15. [PMID: 22102276 DOI: 10.1002/jbm.b.31963] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 08/15/2011] [Accepted: 08/20/2011] [Indexed: 12/13/2022]
Abstract
UNLABELLED Polymethyl methacrylate (PMMA) is widely used to treat traumatic head injuries (cranioplasty) and orthopedic injuries (bone cement), but there is a problem with implant-centered infections. With organisms such as Acinetobacter baumannii and methicillin-resistant staphylococcus aureus developing resistance to antibiotics, there is a need for novel antimicrobial delivery mechanisms without risk of developing resistant organisms. OBJECTIVES To develop a novel antimicrobial implant material by generating silver nanoparticles (AgNP) in situ in PMMA. RESULTS All PMMA samples with AgNP's (AgNP-PMMA) released Ag(+) ions in vitro for over 28 days. In vitro antimicrobial assays revealed that these samples (even samples with the slowest release rate) inhibited 99.9% of bacteria against four different strains of bacteria. Long-term antimicrobial assay showed a continued antibacterial effect past 28 days. Some AgNP-loaded PMMA groups had comparable Durometer-D hardness (a measure of degree of cure) and modulus to control PMMA, but all experimental groups had slightly lower ultimate transverse strengths. CONCLUSIONS AgNP-PMMA demonstrated a tremendously broad-spectrum and long-intermediate-term antimicrobial effect with comparable mechanical properties to control PMMA. Current efforts are focused on further improving mechanical properties by reducing AgNP loading and assessing fatigue properties.
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Affiliation(s)
- James D Oei
- Department of Comprehensive Dentistry, Division of Research, University of Texas Health Science Center San Antonio, San Antonio, Texas
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463
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Krishnamoorthy K, Navaneethaiyer U, Mohan R, Lee J, Kim SJ. Graphene oxide nanostructures modified multifunctional cotton fabrics. APPLIED NANOSCIENCE 2011. [DOI: 10.1007/s13204-011-0045-9] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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464
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Liu Y, Ai K, Lu L. Designing lanthanide-doped nanocrystals with both up- and down-conversion luminescence for anti-counterfeiting. NANOSCALE 2011; 3:4804-4810. [PMID: 21993996 DOI: 10.1039/c1nr10752f] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The widespread forgery in all kinds of paper documents and certificates has become a real threat to society. Traditional fluorescent anti-counterfeiting materials generally exhibit unicolor display and suffer greatly from substitution, thus leading to a poor anti-counterfeiting effect. In this work, unseen but significant enhanced blue down-conversion emission from oleic acid-stabilized lanthanide-doped fluoride nanocrystals is first present and the mechanism is proposed and validated. This not only endows these nanocrystals with dual-mode fluorescence, but also offers a simplified synthesis approach for dual-mode fluorescent nanocrystals involving no further complicated assembly or coating procedures, unlike the traditional methods. Furthermore, by changing the host/dopant combination or the content of dopant, these nanocrystals can exhibit simultaneously multicolor up-conversion emission under excitation at near-infrared light and unalterable blue down-conversion emission under ultraviolet light. A preliminary investigation of their anti-counterfeiting performance has been made, and the results indicate that this color tuning capability and high concealment makes these nanocrystals behave in a similar way to chameleons and can provide a strengthened and more reliable anti-counterfeiting effect.
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Affiliation(s)
- Yanlan Liu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China
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465
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Wang B, Wang X, Lou W, Hao J. Ionic liquid-based stable nanofluids containing gold nanoparticles. J Colloid Interface Sci 2011; 362:5-14. [DOI: 10.1016/j.jcis.2011.06.023] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 06/04/2011] [Accepted: 06/07/2011] [Indexed: 10/18/2022]
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466
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Abstract
The capacity of nanosilver (Ag nanoparticles) to destroy infectious micro-organisms makes it one of the most powerful antimicrobial agents, an attractive feature against "super-bugs" resistant to antibiotics. Furthermore, its plasmonic properties facilitate its employment as a biosensor or bioimaging agent. Here, the interaction of nanosilver with biological systems including bacteria and mammalian cells is reviewed. The toxicity of nanosilver is discussed focusing on Ag+ ion release in liquid solutions. Biomedical applications of nanosilver are also presented capitalizing on its antimicrobial and plasmonic properties and summarizing its advantages, limitations and challenges. Though a lot needs to be learned about the toxicity of nanosilver, enough is known to safely use it in a spectrum of applications with minimal impact to the environment and human health.
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467
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Abdullayev E, Sakakibara K, Okamoto K, Wei W, Ariga K, Lvov Y. Natural tubule clay template synthesis of silver nanorods for antibacterial composite coating. ACS APPLIED MATERIALS & INTERFACES 2011; 3:4040-6. [PMID: 21905653 DOI: 10.1021/am200896d] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Halloysite is naturally available clay mineral with hollow cylindrical geometry and it is available in thousands of tons. Silver nanorods were synthesized inside the lumen of the halloysite by thermal decomposition of the silver acetate, which was loaded into halloysite from an aqueous solution by vacuum cycling. Images of individual ca. 15 nm diameter silver nanorods and nanoparticles were observed with TEM. The presence of silver inside the tubes was also verified with STEM-EDX elemental mapping. Nanorods had crystalline nature with [111] axis oriented ~68° from the halloysite tubule main axis. The composite of silver nanorods encased in clay tubes with the polymer paint was prepared, and the coating antimicrobial activity combined with tensile strength increase was demonstrated. Coating containing up 5% silver loaded halloysite did not change color after light exposure contrary to the sample prepared with loading with unshelled silver nanoparticles. Halloysite tube templates have a potential for scalable manufacturing of ceramic encapsulated metal nanorods for composite materials.
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Affiliation(s)
- Elshad Abdullayev
- Institute for Micromanufacturing, Louisiana Tech University, 911 Hergot Avenue, Ruston, Louisiana 71272, USA
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468
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George C, Kuriakose S, George S, Mathew T. Antifungal activity of silver nanoparticle-encapsulated β-cyclodextrin against human opportunistic pathogens. Supramol Chem 2011. [DOI: 10.1080/10610278.2011.575471] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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469
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Kocer HB, Cerkez I, Worley SD, Broughton RM, Huang TS. N-halamine copolymers for use in antimicrobial paints. ACS APPLIED MATERIALS & INTERFACES 2011; 3:3189-3194. [PMID: 21786779 DOI: 10.1021/am200684u] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A series of copolymers containing units of a novel hydantoinylacrylamide and the sodium salt of 2-(acrylamido)-2-methylpropanesulfonic acid have been synthesized. The homopolymer of the hydantoinylacrylamide compound was insoluble in water, while the copolymers with the sulfonic acid sodium salt were water-dispersible/soluble, with the solution becoming completely transparent when the feed ratio for the copolymer contained 7 parts of the hydantoin moiety to 3 parts of the sodium sulfonate moiety. The polymers were added into a commercial water-based latex paint, and upon drying, the painted surfaces treated with the water-miscible copolymers were rendered antimicrobial following chlorination with dilute household bleach. The chlorinated homopolymer failed to provide an antimicrobial property for the paint because of its tendency to isolate into aggregates in the paint, while the completely miscible copolymers were capable of 6-log inactivation of Staphylococcus aureus and Escherichia coli O157:H7 within 5 min of contact time.
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Affiliation(s)
- Hasan B Kocer
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, United States
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470
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Pongnop W, Sombatsompop K, Kositchaiyong A, Sombatsompop N. Effects of incorporating technique and silver colloid content on antibacterial performance for thermoplastic films. J Appl Polym Sci 2011. [DOI: 10.1002/app.34448] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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471
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Cai LJ, Wang M, Hu Y, Qian DJ, Chen M. Synthesis and mechanistic study of stable water-soluble noble metal nanostructures. NANOTECHNOLOGY 2011; 22:285601. [PMID: 21642757 DOI: 10.1088/0957-4484/22/28/285601] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Sodium salt of poly(4-styrenesulfonic acid-co-maleic acid) (PSSMA) has been employed to prepare a series of stable nanosized metal colloids such as silver, gold, palladium, platinum, and silver-gold alloy nanostructures. All of the as-synthesized products are very stable in water. The metal nanostructures have been directly confirmed by ultraviolet-visible spectroscopy, transmission electron microscopy (TEM), high-resolution TEM, and selected area electron diffraction (SAED), and also characterized by techniques such as Fourier transform infrared spectroscopy (FT-IR) and (1)H NMR. Intensive study has found that the metal ions are most probably reduced by organic radicals, generated from the thermal degradation of PSSMA.
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Affiliation(s)
- Ling-Jian Cai
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, People's Republic of China
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472
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Abstract
The expansion of bacterial antibiotic resistance is a growing problem today. When medical devices are inserted into the body, it becomes especially difficult for the body to clear robustly adherent antibiotic-resistant biofilm infections. In addition, concerns about the spread of bacterial genetic tolerance to antibiotics, such as that found in multiple drug-resistant Staphylococcus aureus (MRSA), have significantly increased of late. As a growing direction in biomaterial design, nanomaterials (materials with at least one dimension less than 100 nm) may potentially prevent bacterial functions that lead to infections. As a first step in this direction, various nanoparticles have been explored for improving bacteria and biofilm penetration, generating reactive oxygen species, and killing bacteria, potentially providing a novel method for fighting infections that is nondrug related. This review article will first examine in detail the mechanisms and applications of some of these nanoparticles, then follow with some recent material designs utilizing nanotechnology that are centered on fighting medical device infections.
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Affiliation(s)
- Erik Taylor
- School of Engineering, Brown University, Providence, RI, USA
| | - Thomas J Webster
- School of Engineering, Brown University, Providence, RI, USA
- Department of Orthopedics, Brown University, Providence, RI, USA
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473
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Bhattacharya S, Biswas J. Role of spacer lengths of gemini surfactants in the synthesis of silver nanorods in micellar media. NANOSCALE 2011; 3:2924-2930. [PMID: 21597607 DOI: 10.1039/c1nr10141b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this work, we have prepared Ag-nanorods using biscationic gemini surfactant micelles as the media by a seed-mediated wet synthesis method. Towards this end, we first synthesized Ag-nanoseeds of diameter ~7 nm stabilized by trisodium citrate (as the capping agent). Then these Ag-nanoseeds were used to synthesize Ag-nanorods of different aspect ratios. With decreasing Ag-nanoseed concentration, the aspect ratios of the Ag-nanorods stabilized by these gemini surfactants increased gradually. Various Ag-nanoseeds and Ag-nanospecies were characterized using UV-Vis spectroscopy (to know the surface plasmon bands), transmission electron microscopy (to find out their particle sizes and distribution), energy-dispersive X-ray spectroscopy and X-ray diffraction. When we used micelles derived from gemini surfactants of shorter spacer -(CH(2))(n)- (n = 2 or 4) to stabilize the Ag-nanorods, the λ(max) of the longitudinal band shifted more towards the blue region compared to that of the gemini surfactant micelles with a longer spacer -(CH(2))(n)- (n = 5, 12) at a given amount of the Ag-nanoseed solution. So, the growth of Ag-nanorods in the gemini micellar solutions depends on the spacer-chain length of gemini surfactants employed.
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Affiliation(s)
- Santanu Bhattacharya
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560 012, India.
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474
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Guzman M, Dille J, Godet S. Synthesis and antibacterial activity of silver nanoparticles against gram-positive and gram-negative bacteria. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2011; 8:37-45. [PMID: 21703988 DOI: 10.1016/j.nano.2011.05.007] [Citation(s) in RCA: 407] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 04/15/2011] [Accepted: 05/04/2011] [Indexed: 11/30/2022]
Abstract
UNLABELLED Synthesis of nanosized particles with antibacterial properties is of great interest in the development of new pharmaceutical products. Silver nanoparticles (Ag NPs) are known to have inhibitory and bactericidal effects. In this article we present the synthesis of Ag NPs prepared by chemical reduction from aqueous solutions of silver nitrate, containing a mixture of hydrazine hydrate and sodium citrate as reductants and sodium dodecyl sulfate as a stabilizer. The results of the characterization of the Ag NPs show agglomerates of grains with a narrow size distribution (from 40 to 60 nm), whereas the radii of the individual particles are between 10 and 20 nm. Finally, the antibacterial activity was measured by the Kirby-Bauer method. The results showed reasonable bactericidal activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The standard dilution micromethod, determining the minimum inhibitory concentration leading to inhibition of bacterial growth, is still under way. Preliminary results have been obtained. FROM THE CLINICAL EDITOR In this paper the synthesis of Ag NPs via chemical reduction from aqueous solutions is discussed. Reasonable bactericidal activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus was demonstrated.
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Affiliation(s)
- Maribel Guzman
- Pontificia Universidad Católica del Perú, Engineering Department, Lima, Peru.
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475
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Silver nanoparticles induce apoptosis and G2/M arrest via PKCζ-dependent signaling in A549 lung cells. Arch Toxicol 2011; 85:1529-40. [DOI: 10.1007/s00204-011-0714-1] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 05/02/2011] [Indexed: 01/27/2023]
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476
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Xu X, Song Z, Shang S, Cui S, Rao X. Synthesis and properties of novel rosin-based water-borne polyurethane. POLYM INT 2011. [DOI: 10.1002/pi.3112] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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477
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Veerapandian M, Yun K. Functionalization of biomolecules on nanoparticles: specialized for antibacterial applications. Appl Microbiol Biotechnol 2011; 90:1655-67. [DOI: 10.1007/s00253-011-3291-6] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 03/25/2011] [Accepted: 03/26/2011] [Indexed: 01/05/2023]
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478
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Dutta S, Shome A, Kar T, Das PK. Counterion-induced modulation in the antimicrobial activity and biocompatibility of amphiphilic hydrogelators: influence of in-situ-synthesized Ag-nanoparticle on the bactericidal property. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:5000-5008. [PMID: 21446701 DOI: 10.1021/la104903z] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The necessity for the development of new antimicrobial agents due to the ever increasing threat from microbes is causing a rapid surge in research. In the present work, we have shown the efficient antimicrobial activity of a series of amino acid-based hydrogelating amphiphiles through alteration in their counterion. The subtle variation in the counterion from chloride to various organic carboxylates had a significant impact on the antimicrobial properties with notable improvement in biocompatibility toward mammalian cells. Incorporation of a hydrophobic moiety in the counterion augmented the antibacterial property of the amphiphilic hydrogelator as minimum inhibitory concentration (MIC) against the Gram-positive bacterial strain, Bacillus subtilis decreased up to 5-fold (with respect to the chloride) in the case of n-hexanoate. These counterion-varied amphiphilic hydrogelators were also found to be effective against fungal strains (Candida albicans and Saccharomyces cerevisiae) where they exhibited MICs in the range of 1.0-12.5 μg/mL. To widen the spectrum of antibacterial activity, particularly against Gram-negative bacteria, silver nanoparticles (AgNPs) were synthesized in situ within the supramolecular assemblies of the carboxylate hydrogelators. These AgNP-amphiphile soft-nanocomposites showed bactericidal property against both Gram-positive and Gram-negative bacteria. Encouragingly, these carboxylate hydrogelators showed superior biocompatibility toward mammalian cells, HepG2 and NIH3T3, as compared to the chloride analogue at a concentration range of 10-200 μg/mL. Importantly, the AgNP composites also showed sufficient viability to mammalian cells. Because of the intrinsic hydrogelation ability of these counterion-varied amphiphiles, the resulting soft materials and the nanocomposites could find applications in biomedicine and tissue engineering.
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Affiliation(s)
- Sounak Dutta
- Department of Biological Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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479
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Deepak V, Umamaheshwaran PS, Guhan K, Nanthini RA, Krithiga B, Jaithoon NMH, Gurunathan S. Synthesis of gold and silver nanoparticles using purified URAK. Colloids Surf B Biointerfaces 2011; 86:353-8. [PMID: 21592748 DOI: 10.1016/j.colsurfb.2011.04.019] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 04/08/2011] [Accepted: 04/08/2011] [Indexed: 10/18/2022]
Abstract
This study aims at developing a new eco-friendly process for the synthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) using purified URAK. URAK is a fibrinolytic enzyme produced by Bacillus cereus NK1. The enzyme was purified and used for the synthesis of AuNPs and AgNPs. The enzyme produced AgNPs when incubated with 1 mM AgNO3 for 24 h and AuNPs when incubated with 1 mM HAuCl4 for 60 h. But when NaOH was added, the synthesis was rapid and occurred within 5 min for AgNPs and 12 h for AuNPs. The synthesized nanoparticles were characterized by a peak at 440 nm and 550 nm in the UV-visible spectrum. TEM analysis showed that AgNPs of the size 60 nm and AuNPs of size 20 nm were synthesized. XRD confirmed the crystalline nature of the nanoparticles and AFM showed the morphology of the nanoparticle to be spherical. FT-IR showed that protein was responsible for the synthesis of the nanoparticles. This process is highly simple, versatile and produces AgNPs and AuNPs in environmental friendly manner. Moreover, the synthesized nanoparticles were found to contain immobilized enzyme. Also, URAK was tested on RAW 264.7 macrophage cell line and was found to be non-cytotoxic until 100 μg/ml.
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Affiliation(s)
- Venkataraman Deepak
- Division of Molecular and Cellular Biology, Department of Biotechnology, Kalasalingam University, Anand Nagar, Krishnankoil 626190, Tamil Nadu, India
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480
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Prabhakar PK, Raj S, Anuradha PR, Sawant SN, Doble M. Biocompatibility studies on polyaniline and polyaniline-silver nanoparticle coated polyurethane composite. Colloids Surf B Biointerfaces 2011; 86:146-53. [PMID: 21501952 DOI: 10.1016/j.colsurfb.2011.03.033] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 02/15/2011] [Accepted: 03/23/2011] [Indexed: 10/18/2022]
Abstract
Biocompatibility of medical grade polyurethane coated with polyaniline (PANi) and polyaniline-silver nanoparticle composite (PANi-AgNp) is reported here. These modified films showed 23 and 18% of 3T3 L1 cell death when compared to 41% with virgin polyurethane (PU) after 48h of incubation, respectively. All the surfaces elucidated inflammatory response in the form of enhanced expressions of the proinflammatory cytokines genes, TNF-α and IL-6. But these values were less (by 20%) on modified films than on the bare PU. Attachment of Pseudomonas and Bacillus were markedly less on PANi-AgNp coated surface (by 90.6 and 50.5%, respectively) when compared to the uncoated PU. As the CFU counts decreases on the nanoparticle coated PU, the adsorbed carbohydrate as well as protein content on to the surface of polymer decreases accordingly, indicating less attachment. A 20% reduction in the thickness of biofilm was observed in PANi-AgNp coated PU surface. A very strong positive correlation is observed between the contact angles of the polymers and the various biological parameters (namely colony forming units, protein, carbohydrate, cell death and inflammatory response), indicating hydrophilic surfaces prevent bacterial biofilm as well as are compatible to cells when compared to hydrophobic surfaces. Coating PU with PANi and PANi+AgNp renders the surface conductive, suggesting potential application in electrochemical biosensors. In addition, these modifications make the surface more biocompatible than the original PU.
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Affiliation(s)
- Pranav Kumar Prabhakar
- Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600 036, India
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481
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Zhou C, Li P, Qi X, Sharif ARM, Poon YF, Cao Y, Chang MW, Leong SSJ, Chan-Park MB. A photopolymerized antimicrobial hydrogel coating derived from epsilon-poly-l-lysine. Biomaterials 2011; 32:2704-12. [DOI: 10.1016/j.biomaterials.2010.12.040] [Citation(s) in RCA: 156] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2010] [Accepted: 12/27/2010] [Indexed: 12/25/2022]
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482
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Liu L, Ni F, Zhang J, Jiang X, Lu X, Guo Z, Xu R. Silver nanocrystals sensitize magnetic-nanoparticle-mediated thermo-induced killing of cancer cells. Acta Biochim Biophys Sin (Shanghai) 2011; 43:316-23. [PMID: 21377996 DOI: 10.1093/abbs/gmr015] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Magnetic nanoparticles (MNPs) can heat up tumor tissues and induce killing of cancer cells under external AC magnetic field. However, magnetic nanoparticles hyperthermia (MNPH) requires high concentration of MNPs that are injected into the tumor in order to obtain clinically needed thermal dose because of the complicated heat transfer in vivo and the limited heat quality of MNPs. To cut down the dose of MNPs and enhance the effect of this Nanotherapy, we prepared silver nanoparticles (AgNPs) with different sizes and investigated the effects of these AgNPs on cancer cells in MNPH treatment. It was found that AgNPs could enhance thermo-sensitivity of glioma cells and this effect was size dependent. AgNPs could induce cell cycles arrested in G(2)/M phase and enhanced the apoptosis rate of cancer cells after hyperthermia. In glioma bearing rats model, MNPH combined with AgNPs could enhance Bax expression in cancer cells. Our results suggested that AgNPs could be a potential thermo-sensitizer and could be further developed for the design of Ag nanostructure-based thermal seeds for MNPH therapy.
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Affiliation(s)
- Lianke Liu
- Department of Oncology, Jiangsu Province Hospital, the First Affiliated Hospital of Nanjing Medical University, China
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483
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Antifungal activity of zinc oxide nanoparticles against Botrytis cinerea and Penicillium expansum. Microbiol Res 2011; 166:207-15. [PMID: 20630731 DOI: 10.1016/j.micres.2010.03.003] [Citation(s) in RCA: 359] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 03/10/2010] [Accepted: 03/11/2010] [Indexed: 11/23/2022]
Abstract
Antifungal activities of zinc oxide nanoparticles (ZnO NPs) and their mode of action against two postharvest pathogenic fungi (Botrytis cinerea and Penicillium expansum) were investigated in this study. ZnO NPs with sizes of 70 ± 15 nm and concentrations of 0, 3, 6 and 12 mmol l(-1) were used. Traditional microbiological plating, scanning electron microscopy (SEM), and Raman spectroscopy were used to study antifungal activities of ZnO NPs and to characterize the changes in morphology and cellular compositions of fungal hyphae treated with ZnO NPs. Results show that ZnO NPs at concentrations greater than 3 mmol l(-1) can significantly inhibit the growth of B. cinerea and P. expansum. P. expansum was more sensitive to the treatment with ZnO NPs than B. cinerea. SEM images and Raman spectra indicate two different antifungal activities of ZnO NPs against B. cinerea and P. expansum. ZnO NPs inhibited the growth of B. cinerea by affecting cellular functions, which caused deformation in fungal hyphae. In comparison, ZnO NPs prevented the development of conidiophores and conidia of P. expansum, which eventually led to the death of fungal hyphae. These results suggest that ZnO NPs could be used as an effective fungicide in agricultural and food safety applications.
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484
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Devi DK, Pratap SV, Haritha R, Sivudu KS, Radhika P, Sreedhar B. Gum acacia as a facile reducing, stabilizing, and templating agent for palladium nanoparticles. J Appl Polym Sci 2011. [DOI: 10.1002/app.33004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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485
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Synthesis of silver nanoparticles in an aqueous suspension of graphene oxide sheets and its antimicrobial activity. Colloids Surf B Biointerfaces 2011; 83:16-22. [DOI: 10.1016/j.colsurfb.2010.10.033] [Citation(s) in RCA: 363] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 10/15/2010] [Accepted: 10/19/2010] [Indexed: 02/07/2023]
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486
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Das S, Pandey AK, Athawale AA, Subramanian M, Seshagiri TK, Khanna PK, Manchanda VK. Silver nanoparticles embedded polymer sorbent for preconcentration of uranium from bio-aggressive aqueous media. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:2051-2059. [PMID: 21269770 DOI: 10.1016/j.jhazmat.2010.12.132] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 12/17/2010] [Accepted: 12/23/2010] [Indexed: 05/30/2023]
Abstract
Adsorptive sorbent for bio-aggressive natural aqueous media like seawater was developed by one pot simultaneous synthesis of silver nanoparticles (Ag nps) and poly(ethylene glycol methacrylate phosphate) (PEGMP) by UV-initiator induced photo-polymerization. The photo-polymerization was carried out by irradiating N,N'-dimethylformamide (DMF) solution containing appropriate amounts of the functional monomer (ethylene glycol methacrylate phosphate), UV initiator (α,α'-dimethoxy-α-phenyl acetophenone), and Ag(+) ions with 365 nm UV light in a multilamps photoreactor. To increase mechanical strength, nano-composite sorbent (Ag@PEGMP) was also reinforced with thermally bonded non-woven poly(propylene) fibrous sheet. Transmission electron microscopy (TEM) of the nano-composite sorbent showed uniform distribution of spherical Ag nanoparticles with particles size ranging from 3 to 6 nm. The maximum amount of Ag(0) that could be anchored in the form of nanoparticles were 5±1 and 10±1 wt.% in self-supported PEGMP and poly(propylene) reinforced PEGMP matrices, respectively. Ag@PEGMP sorbent was found to be stable under ambient conditions for a period of six months. Ag@PEGMP composite sorbent did not exhibit growth at all after incubation with pre-grown Escherichia coli cells, and showed non-adherence of this bacteria to the composite. This indicated that composite sorbent has the bio-resistivity due to bacterial repulsion and bactericidal properties of Ag nanoparticles embedded in the PEGMP. Sorption of U(VI) in PEGMP and Ag@PEGMP nano-composite sorbents from well-stirred seawater was studied to explore the possibility of using it for uranium preconcentration from bio-aggressive aqueous streams. The nano-composite sorbent was used to preconcentrate U(VI) from a process aqueous waste stream.
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Affiliation(s)
- Sadananda Das
- Department of Chemistry, University of Pune, Pune 411 007, India
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487
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Fages E, Pascual J, Fenollar O, García-Sanoguera D, Balart R. Study of antibacterial properties of polypropylene filled with surfactant-coated silver nanoparticles. POLYM ENG SCI 2011. [DOI: 10.1002/pen.21889] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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488
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Banerjee I, Pangule RC, Kane RS. Antifouling coatings: recent developments in the design of surfaces that prevent fouling by proteins, bacteria, and marine organisms. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:690-718. [PMID: 20886559 DOI: 10.1002/adma.201001215] [Citation(s) in RCA: 1571] [Impact Index Per Article: 120.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Revised: 06/06/2010] [Indexed: 05/21/2023]
Abstract
The major strategies for designing surfaces that prevent fouling due to proteins, bacteria, and marine organisms are reviewed. Biofouling is of great concern in numerous applications ranging from biosensors to biomedical implants and devices, and from food packaging to industrial and marine equipment. The two major approaches to combat surface fouling are based on either preventing biofoulants from attaching or degrading them. One of the key strategies for imparting adhesion resistance involves the functionalization of surfaces with poly(ethylene glycol) (PEG) or oligo(ethylene glycol). Several alternatives to PEG-based coatings have also been designed over the past decade. While protein-resistant coatings may also resist bacterial attachment and subsequent biofilm formation, in order to overcome the fouling-mediated risk of bacterial infection it is highly desirable to design coatings that are bactericidal. Traditional techniques involve the design of coatings that release biocidal agents, including antibiotics, quaternary ammonium salts (QAS), and silver, into the surrounding aqueous environment. However, the emergence of antibiotic- and silver-resistant pathogenic strains has necessitated the development of alternative strategies. Therefore, other techniques based on the use of polycations, enzymes, nanomaterials, and photoactive agents are being investigated. With regard to marine antifouling coatings, restrictions on the use of biocide-releasing coatings have made the generation of nontoxic antifouling surfaces more important. While considerable progress has been made in the design of antifouling coatings, ongoing research in this area should result in the development of even better antifouling materials in the future.
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Affiliation(s)
- Indrani Banerjee
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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489
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Cao H, Liu X. Silver nanoparticles-modified films versus biomedical device-associated infections. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2011; 2:670-84. [PMID: 20730806 DOI: 10.1002/wnan.113] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A serious issue related to biomedical devices (BDs) is that of bacterial infections. BDs colonized by bacteria may cause infection or mortality. To prevent such infections, an effective strategy is to develop novel BDs with antibacterial abilities via various surface modification processes. Thus, plenty of silver nanoparticles (Ag NPs)-modified films were brought forward to because of their potential applications in improving the antibacterial properties of BDs. This article reviews the difficulties in diagnosing and treating biomedical device-associated infections as well as the state of arts in fabricating the Ag NPs-modified films for antibacterial applications. In addition, the nanoeffect of silver particles and the cytotoxicity of Ag NPs are also discussed. It is clear that safe and durable Ag NPs-modified films are more desirable for the BDs prone to bacteria. To further extend the investigations on controlling the toxicity path of Ag NPs to both bacteria and mammalian cells, developing novel green fabrication processes with more 'cleaner' (without accompaniment of ligands or reduction agents) Ag NPs should be the first mission for the material scientists to complete.
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Affiliation(s)
- Huiliang Cao
- Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai, People's Republic of China
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490
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Piao L, Lee KH, Min BK, Kim W, Do YR, Yoon SH. A Facile Synthetic Method of Silver Nanoparticles with a Continuous Size Range from sub-10 nm to 40 nm. B KOREAN CHEM SOC 2011. [DOI: 10.5012/bkcs.2011.32.1.117] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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491
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Gottesman R, Shukla S, Perkas N, Solovyov LA, Nitzan Y, Gedanken A. Sonochemical coating of paper by microbiocidal silver nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:720-726. [PMID: 21155556 DOI: 10.1021/la103401z] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Colloidal silver has gained wide acceptance as an antimicrobial agent, and various substrates coated with nanosilver such as fabrics, plastics, and metal have been shown to develop antimicrobial properties. Here, a simple method to develop coating of colloidal silver on paper using ultrasonic radiation is presented, and the coatings are characterized using X-ray diffraction (XRD), high resolution scanning electron microscope (HRSEM), and thermogravimetry (TGA) measurements. Depending on the variables such as precursor concentrations and ultrasonication time, uniform coatings ranging from 90 to 150 nm in thickness have been achieved. Focused ion beam (FIB) cross section imaging measurements revealed that silver nanoparticles penetrated the paper surface to a depth of more than 1 μm, resulting in highly stable coatings. The coated paper demonstrated antibacterial activity against E. coli and S. aureus, suggesting its potential application as a food packing material for longer shelf life.
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Affiliation(s)
- Ronen Gottesman
- Department of Chemistry, Kanbar Laboratory for Nanomaterials, Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan 52900, Israel
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492
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Hwang SH, Song J, Jung Y, Kweon OY, Song H, Jang J. Electrospun ZnO/TiO2 composite nanofibers as a bactericidal agent. Chem Commun (Camb) 2011; 47:9164-6. [DOI: 10.1039/c1cc12872h] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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493
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Lalueza P, Monzón M, Arruebo M, Santamaria J. Antibacterial action of Ag-containing MFI zeolite at low Ag loadings. Chem Commun (Camb) 2011; 47:680-2. [DOI: 10.1039/c0cc03905e] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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494
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Song J, Song H, Kong H, Hong JY, Jang J. Fabrication of silica/polyrhodanine core/shell nanoparticles and their antibacterial properties. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm13017j] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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495
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Liu L, Liu J, Wang Y, Yan X, Sun DD. Facile synthesis of monodispersed silver nanoparticles on graphene oxide sheets with enhanced antibacterial activity. NEW J CHEM 2011. [DOI: 10.1039/c1nj20076c] [Citation(s) in RCA: 165] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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496
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Song T, Gao Y, Zhang Z, Zhai Q. Dealloying behavior of rapidly solidified Al–Ag alloys to prepare nanoporous Ag in inorganic and organic acidic media. CrystEngComm 2011. [DOI: 10.1039/c1ce05538k] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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497
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Philip D. Mangifera indica leaf-assisted biosynthesis of well-dispersed silver nanoparticles. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 78:327-331. [PMID: 21030295 DOI: 10.1016/j.saa.2010.10.015] [Citation(s) in RCA: 134] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 10/01/2010] [Indexed: 05/30/2023]
Abstract
The use of various parts of plants for the synthesis of nanoparticles is considered as a green technology as it does not involve any harmful chemicals. The present study reports a facile and rapid biosynthesis of well-dispersed silver nanoparticles. The method developed is environmentally friendly and allows the reduction to be accelerated by changing the temperature and pH of the reaction mixture consisting of aqueous AgNO3 and Mangifera Indica leaf extract. At a pH of 8, the colloid consists of well-dispersed triangular, hexagonal and nearly spherical nanoparticles having size ∼20 nm. The UV-vis spectrum of silver nanoparticles gave surface plasmon resonance (SPR) at 439 nm. The synthesized nanocrystals were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Water soluble organics present in the leaf are responsible for the reduction of silver ions. This green method provides faster synthesis comparable to chemical methods and can be used in areas such as cosmetics, foods and medical applications.
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Affiliation(s)
- Daizy Philip
- Department of Physics, Mar Ivanios College, Thiruvananthapuram 695015, India.
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498
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Lv M, Su S, He Y, Huang Q, Hu W, Li D, Fan C, Lee ST. Long-term antimicrobial effect of silicon nanowires decorated with silver nanoparticles. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:5463-5467. [PMID: 21089062 DOI: 10.1002/adma.201001934] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Affiliation(s)
- Min Lv
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, P R China
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499
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Huang S, He S, Lu Y, Wei F, Zeng X, Zhao L. Highly sensitive and selective fluorescent chemosensor for Ag+ based on a coumarin-Se2N chelating conjugate. Chem Commun (Camb) 2010; 47:2408-10. [PMID: 21165497 DOI: 10.1039/c0cc04589f] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A highly sensitive and selective fluorescent chemosensor SC1 for Ag(+) based on a coumarin-Se(2)N chelating conjugate has been synthesized and characterized. Due to inhibiting a photoinduced electron transfer (PET) quenching pathway, a fluorescent enhancement factor of 4-fold is observed under the binding of the Ag(+) cation to the chemosensor SC1 with a detection limit down to the 10(-8) M range.
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Affiliation(s)
- Shanshan Huang
- Key Laboratory of Display Materials & Photoelectric Devices, Ministry of Education, School of Materials Science & Engineering, Tianjin University of Technology, Tianjin 300384, China
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500
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Pugh S, McKenna R, Moolick R, Nielsen DR. Advances and opportunities at the interface between microbial bioenergy and nanotechnology. CAN J CHEM ENG 2010. [DOI: 10.1002/cjce.20434] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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