Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/23056
標題: 奈米銀脫層黏土抗菌機制之探討
Antibacterial mechanisms of the nanohybrid of the immobilized silver nanoparticles and exfoliated platelet clay
作者: 林秀鴻
Lin, Siou-Hong
關鍵字: silver nanoparticles;奈米銀;antibacteria;exfoliated clay;抗菌;脫層黏土
出版社: 生命科學系所
引用: References 1. Joseph JC, Susan MS, Francis K, Guillermo D, Terry EW, Rudolph JM, et al. Comparative evaluation of silver-containing antimicrobial dressings and drugs. International Wound Journal 2007;4(2):114-122. 2. Klasen H. Historical review of the use of silver in the treatment of burns. I. Early uses. Burns 2000;26(2):117-130. 3. Chopra I. The increasing use of silver-based products as antimicrobial agents: a useful development or a cause for concern?--author''s response. J Antimicrob Chemother, 2007. 4. Moyer CA, Brentano L, Gravens DL, Margraf HW, Monafo WWJ. Treatment of Large Human Burns With 0.5% Silver Nitrate Solution. AMA Arch Surg,1965;90(6):812-867. 5. Q. L. Feng, Wu J, Chen GQ, Cui FZ, Kim TN, Kim JO. A mechanistic study of the antibacterial effect of silver ions on Escherichia coli and Staphylococcus aureus. Journal of Biomedical Materials Research 2000;52(4):662-668. 6. Yamanaka M, Hara K, Kudo J. Bactericidal Actions of a Silver Ion Solution on Escherichia coli, Studied by Energy-Filtering Transmission Electron Microscopy and Proteomic Analysis. Appl Environ Microbiol, 2005;71(11):7589-7593. 7. Vincenzo A, Stefano P, Moreno M. Free silver nanoparticles synthesized by laser ablation in organic solvents and their easy functionalization. Langmuir 2007 23(12):6766-6670. 8. Kapoor S LD, Kennepohl P, Meisel D, Serpone N. Reduction and aggregation of silver ions in aqueous gelatin solutions. Langmuir 1994;10:3018. 9. Benjamin W, Yugang S, Brian M, Younan X. Shape-Controlled Synthesis of Metal Nanostructures: The Case of Silver. Chemistry - A European Journal 2005;11(2):454-463. 10. Andrea T, Prasert S, Peidong Y. Polyhedral Silver Nanocrystals with Distinct Scattering Signatures13. Angewandte Chemie International Edition 2006;45(28):4597-4601. 11. Tan S EM, Attygalle A, Du H, Sukhishvili S. Synthesis of positively charged silver nanoparticles via photoreduction of AgNO3 in branched polyethyleneimine/HEPES solutions. Langmuir 2007;23:9836-9843. 12. Lok C-N, Ho C-M, Chen R, He Q-Y, Yu W-Y, Sun H, et al. Proteomic Analysis of the Mode of Antibacterial Action of Silver Nanoparticles. Journal of Proteome Research 2006;5(4):916-924. 13. Baker C PA, Pakstis L, Pochan DJ, Shah SI. Synthesis and antibacterial properties of silver nanoparticles. Journal of nanoscience and nanotechnology 2005;5:244-249. 14. Pal S, Tak YK, Song JM. Does the Antibacterial Activity of Silver Nanoparticles Depend on the Shape of the Nanoparticle? A Study of the Gram-Negative Bacterium Escherichia coli. Appl Environ Microbiol, 2007;73(6):1712-1720. 15. Sondi I, Salopek-Sondi B. Silver nanoparticles as antimicrobial agent: a case study on E. coli as a model for Gram-negative bacteria. Journal of Colloid and Interface Science 2004;275(1):177-182. 16. Jose Ruben M, Jose Luis E, Alejandra C, Katherine H, Juan BK, Jose Tapia R, et al. The bactericidal effect of silver nanoparticles. Nanotechnology 2005(10):2346. 17. Song HY KK, Oh LH, Lee BT. Fabrication of silver nanoparticles and their antimicrobial mechanisms. Eur Cells Mater 2006;11:58. 18. Lok C-N, Ho C-M, Chen R, Tam PK-H, Chiu J-F, Che C-M. Proteomic Identification of the Cus System as a Major Determinant of Constitutive Escherichia coli Silver Resistance of Chromosomal Origin. Journal of Proteome Research 2008;7(6):2351-2356. 19. Balan L, Schneider R, Lougnot DJ. A new and convenient route to polyacrylate/silver nanocomposites by light-induced cross-linking polymerization. Progress in Organic Coatings 2008;62(3):351-357. 20. Haefeli C, Franklin C, Hardy K. Plasmid-determined silver resistance in Pseudomonas stutzeri isolated from a silver mine. J Bacteriol, 1984;158(1):389-392. 21. Kaur P SM, Vadehra DV. Plasmid mediated resistance to silver ions in Escherichia coli. Indian J Med Res 1985;82:122-126. 22. Kaur P, Vadehra DV. Mechanism of resistance to silver ions in Klebsiella pneumoniae. Antimicrob Agents Chemother, 1986;29(1):165-167. 23. Gupta A, Matsui K, Lo J-F, Silver S. Molecular basis for resistance to silver cations in Salmonella. Nat Med 1999;5(2):183-188. 24. Vasilev K, Sah V, Anselme K, Ndi C, Mateescu M, Dollmann Br, et al. Tunable Antibacterial Coatings That Support Mammalian Cell Growth. Nano Letters 2009. 25. P V Asharani YLWZG, Suresh V. Toxicity of silver nanoparticles in zebrafish models. Nanotechnology 2008;19(25):255102. 26. Van Houdt R, Michiels CW. Role of bacterial cell surface structures in Escherichia coli biofilm formation. Research in Microbiology, 2005;156(5-6):626-633. 27. Leslie AP, Roberto K. Genetic analysis of Escherichia coli biofilm formation: roles of flagella, motility, chemotaxis and type I pili. Molecular Microbiology 1998;30(2):285-293. 28. Eby DM, Schaeublin NM, Farrington KE, Hussain SM, Johnson GR. Lysozyme Catalyzes the Formation of Antimicrobial Silver Nanoparticles. ACS Nano 2009;3(4):984-994.
摘要: 
銀自古以來即被使用在防腐、抗菌、淨水等用途。銀及其化合物因其傑出的抗菌能力與低細胞毒性亦被廣泛使用在醫療領域,例如創傷敷料、防止燙傷感染等。由銀化合物中解離出的銀離子,其機制也廣泛被研究。例如存在硝酸銀溶液中的銀離子,透過與蛋白質的硫氫基 (Thiol group)作用,破壞細菌蛋白正常功能抑制細菌生長。近年來奈米科技蓬勃發展,奈米是一長度單位,代表10-9m,也就是十億分之一公尺,在此尺度下,許多物質的物理化學性質會出現變化。許多研究者看中銀具抗菌能力且較低細胞毒性的特性,將金屬銀製成奈米等級的奈米銀粒子,對各種病原體的抗菌能力進行廣泛測試,包括格蘭氏陽性菌、格蘭氏陰性菌、真菌甚至是HIV病毒等。單純奈米銀粒子的抗菌能力已經被證實優於銀離子,奈米銀粒子在nanomole等級的濃度即可有效殺菌,而銀離子的有效殺菌濃度則需micromole等級。本實驗的研究材料使用天然奈米脫層黏土(NSP)作為奈米銀粒子的分散劑,將其固定在黏土上,形成奈米銀/奈米脫層黏土(AgNP/NSP)的複合材料。為瞭解此材料的抗菌能力並探討其機制,本研究使用了場發式電子顯微鏡觀察細菌與材料作用的外觀,發現黏土本身即可黏附細菌。過氧化活性物質指示染劑H2DCFDA氧化態為綠螢光形式,透過使用此指示劑,我們進一步發現奈米銀脫層黏土可使細菌產生自由基,而PI/syto9染色顯示經過奈米銀脫層黏土處理後的細菌,細胞膜受損或死亡,因此我們推斷產生的自由基對細菌細胞膜產生氧化壓力特別是細胞膜的脂質過氧化而破壞其完整性最終導致細胞死亡,Glutathione抗氧化劑恢復細胞生存率實驗結果亦能反證活性氧化物質是使細菌死亡的主要因素。細胞營養物質的攝取測試結果也顯示奈米銀脫層黏土降低了細菌攝取碳源的能力,顯著下降的細胞內ATP濃度也與此結果相呼應。在此研究中我們揭露了此新穎奈米複合材料的抗菌機制,希望能為未來更安全更有效率的奈米抗菌材料設計提供參考。

Silver is well known for its antimicrobial activity. Due to the extraordinary antibacterial activity, silver and its compound are widely used in medical filed such as wound healing and burns infections. The antibacterial mechanisms of silver ions that dissociated from silver compounds have been studied by many researchers. For instance, silver ions that dissociated from silver nitrate disrupt normal cell function and inhibit cell growth by binding with thiol group in protein. Recent years, nanotechnology developed prosperously. Nano is 10-9 or billionth of one meter. Silver nanoparticles were synthesis for the advantage of its antibacterial activity and low cytotoxicity to eukaryotic cells. The antibacterial activity of silver nanoparticles against broad-spectrum strain of bacteria has been studied, including gram-positive, gram-negative, fungi and even HIV virus. In this study, we have used a novel nanohybrid that consisted of silver nanoparticles and exfoliated nature silicate clay (AgNP/NSP). Silicate clay served as disperse for silver ions in situ reduced into immobilized silver nanoparticeles. To elucidate the antibacterial mechanisms of this nanocomposite, several experiments were applied. FE-SEM observation revealed the morphology of AgNP/NSP treated cells. Reactive oxygen species (ROS) detecting assay indicated the generation of ROS may be the major contributor for the cell membrane damage consistent with the result of Live/Dead assay that AgNP/NSP post-treated cells were dead. And according to the result of free radicals scavengers blocking ROS generation experiment, we can speculate that ROS is mainly result in lipidperoxidation leading to cell membrane damage and cell death. A strong antioxidant glutathione rescued bacteria cells survival rate from AgNP/NSP containing plates also a result consistent with above hypothesis. We also demonstrated that the glucose uptake of cells was diminished by treating AgNP/NSP. The intracellular ATP level of AgNP/NSP post-treated cells also decreased. These results indicat that AgNP/NSP hinder the normal cell physiological function such as metabolism and energy production. In this study, we have elucidated the mechanisms of AgNP/NSP and hope it will be helpful for future design of safer and more sophisticated antibacterial materials.
URI: http://hdl.handle.net/11455/23056
其他識別: U0005-1307201022125600
Appears in Collections:生命科學系所

Show full item record
 

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.