Facile preparation and characterization of highly antimicrobial colloid Ag or Au nanoparticles.

A series of colloid silver or gold nanoparticles (AgNPs or AuNPs) were successfully prepared by in situ reduction and stabilization of hyperbranched poly(amidoamine) with terminal dimethylamine groups (HPAMAM-N(CH(3))(2)) in water, and they all exhibited highly antimicrobial activity. The particle size could be controlled easily by adjusting the molar ratio of N/Ag (or N/Au) in feed. When the molar ratio was 2, some aggregates of the nanoparticles separated from the colloidal solution, which showed some limited antimicrobial activity with the bacterial inhibition ratio of below 15%. As the molar ratio increased from 10 to 30, the average particle diameters decreased (from ca. 7.1 to 1.0 nm for AgNPs and from ca. 7.7 to 3.9 nm for AuNPs, respectively) and they all showed high dispersion stability and excellent antimicrobial efficiency. All the bacterial inhibition ratios reached up to ca. 98% at the low silver content of ca. 2.0 microg/mL or at the low gold content of ca. 2.8 microg/mL. The AgNPs or AuNPs with smaller particle size can provide much more effective contact surface with the bacteria, thus enhancing their antimicrobial efficiency. Besides, the cationic HPAMAM-N(CH(3))(2) can also do some contribution to the antimicrobial activity through the strong ionic interaction with the bacteria.

[1]  M. Sastry,et al.  Free‐Standing Gold Nanoparticle Membrane by the Spontaneous Reduction of Aqueous Chloroaurate Ions by Oxyethylene‐Linkage‐Bearing Diamine at a Liquid–Liquid Interface , 2004 .

[2]  P. Jain,et al.  Potential of silver nanoparticle-coated polyurethane foam as an antibacterial water filter. , 2005, Biotechnology and bioengineering.

[3]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[4]  D. Astruc,et al.  Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology. , 2004, Chemical reviews.

[5]  J. Xin,et al.  Novel core-shell particles with poly(n-butyl acrylate) cores and chitosan shells as an antibacterial coating for textiles , 2005 .

[6]  Xiabin Jing,et al.  Preparation and antibacterial effects of PVA‐PVP hydrogels containing silver nanoparticles , 2007 .

[7]  S. Shanmugam,et al.  A novel single step chemical route for noble metal nanoparticles embedded organic–inorganic composite films , 2006 .

[8]  Ye Liu,et al.  Preparation and characterization of novel hyperbranched poly(amido amine)s from Michael addition polymerizations of trifunctional amines with diacrylamides , 2005 .

[9]  F. Cui,et al.  A mechanistic study of the antibacterial effect of silver ions on Escherichia coli and Staphylococcus aureus. , 2000, Journal of biomedical materials research.

[10]  Bing Xu,et al.  Presenting Vancomycin on Nanoparticles to Enhance Antimicrobial Activities , 2003 .

[11]  T. Uemura,et al.  Synthesis of Novel Stable Nanometer-Sized Metal (M = Pd, Au, Pt) Colloids Protected by a π-Conjugated Polymer , 2002 .

[12]  D. Yan,et al.  Hyperbranched Polymers Made from A2 and BB‘2 Type Monomers. 1. Polyaddition of 1-(2-Aminoethyl)piperazine to Divinyl Sulfone , 2000 .

[13]  D. Shieh,et al.  One-pot synthesis of hollow Au3Cu1 spherical-like and biomineral botallackite Cu2(OH)3Cl flowerlike architectures exhibiting antimicrobial activity. , 2006, The journal of physical chemistry. B.

[14]  Dulal Panda,et al.  Anticancer and antimicrobial metallopharmaceutical agents based on palladium, gold, and silver N-heterocyclic carbene complexes. , 2007, Journal of the American Chemical Society.

[15]  R. Larossa,et al.  Quaternary ammonium functionalized poly(propylene imine) dendrimers as effective antimicrobials: structure-activity studies. , 2000, Biomacromolecules.

[16]  J. E. Gray,et al.  Biological efficacy of electroless-deposited silver on plasma activated polyurethane. , 2003, Biomaterials.

[17]  T. Pradeep,et al.  Ciprofloxacin-protected gold nanoparticles. , 2004, Langmuir : the ACS journal of surfaces and colloids.

[18]  Richard M. Crooks,et al.  Patterning bacteria within hyperbranched polymer film templates , 2002 .

[19]  P. Vary,et al.  Anatase TiO2 nanocomposites for antimicrobial coatings. , 2005, The journal of physical chemistry. B.

[20]  M. Yacamán,et al.  The bactericidal effect of silver nanoparticles , 2005, Nanotechnology.

[21]  Ayusman Sen,et al.  Silver bromide nanoparticle/polymer composites: dual action tunable antimicrobial materials. , 2006, Journal of the American Chemical Society.

[22]  K. Leong,et al.  Hyperbranched poly(amino ester)s with different terminal amine groups for DNA delivery. , 2006, Biomacromolecules.

[23]  T. Aida,et al.  Dendritic physical gels: Structural parameters for gelation with peptide-core dendrimers , 2003 .

[24]  Qingsheng Wu,et al.  Synergistic antibacterial effects of β-lactam antibiotic combined with silver nanoparticles , 2005 .

[25]  Kwan Kim,et al.  A practical procedure for producing silver nanocoated fabric and its antibacterial evaluation for biomedical applications. , 2007, Chemical communications.

[26]  Amy Milsted,et al.  Silver(I)-imidazole cyclophane gem-diol complexes encapsulated by electrospun tecophilic nanofibers: formation of nanosilver particles and antimicrobial activity. , 2005, Journal of the American Chemical Society.

[27]  Ramesh C. Patel,et al.  Stable Silver Clusters and Nanoparticles Prepared in Polyacrylate and Inverse Micellar Solutions , 2000 .

[28]  C. Ni,et al.  Antibacterial properties of silver-doped titania. , 2007, Small.

[29]  P. Kuo,et al.  Effects of polymer micelles of alkylated polyethylenimines on generation of gold nanoparticles. , 2005, The journal of physical chemistry. B.

[30]  Tomokazu Yoshimura,et al.  Preparation of PAMAM- and PPI-metal (silver, platinum, and palladium) nanocomposites and their catalytic activities for reduction of 4-nitrophenol. , 2004, Langmuir : the ACS journal of surfaces and colloids.

[31]  M. Galleni,et al.  New antibacterial cationic surfactants prepared by atom transfer radical polymerization , 2006 .

[32]  L. Yao,et al.  Antimicrobial effect of surgical masks coated with nanoparticles. , 2006, The Journal of hospital infection.

[33]  I. Sondi,et al.  Silver nanoparticles as antimicrobial agent: a case study on E. coli as a model for Gram-negative bacteria. , 2004, Journal of colloid and interface science.

[34]  J. Nah,et al.  A degradable hyperbranched poly(ester amine) based on poloxamer diacrylate and polyethylenimine as a gene carrier. , 2007, Macromolecular bioscience.

[35]  Yongfeng Zhou,et al.  Hyperbranched Poly(amidoamine) as the Stabilizer and Reductant To Prepare Colloid Silver Nanoparticles in Situ and Their Antibacterial Activity , 2008 .

[36]  J. Feijen,et al.  A versatile family of degradable non-viral gene carriers based on hyperbranched poly(ester amine)s. , 2005, Journal of controlled release : official journal of the Controlled Release Society.