<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fang, Bing</style></author><author><style face="normal" font="default" size="100%">Jiang, Ying</style></author><author><style face="normal" font="default" size="100%">Rotello, Vincent M</style></author><author><style face="normal" font="default" size="100%">Nüsslein, Klaus</style></author><author><style face="normal" font="default" size="100%">Santore, Maria M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Easy come easy go: surfaces containing immobilized nanoparticles or isolated polycation chains facilitate removal of captured Staphylococcus aureus by retarding bacterial bond maturation.</style></title><secondary-title><style face="normal" font="default" size="100%">ACS Nano</style></secondary-title><alt-title><style face="normal" font="default" size="100%">ACS Nano</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Nanoparticles</style></keyword><keyword><style  face="normal" font="default" size="100%">Polyamines</style></keyword><keyword><style  face="normal" font="default" size="100%">Staphylococcus aureus</style></keyword><keyword><style  face="normal" font="default" size="100%">Surface Properties</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2014</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2014 Feb 25</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">1180-90</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Adhesion of bacteria is a key step in the functioning of antimicrobial surfaces or certain types of on-line sensors. The subsequent removal of these bacteria, within a &amp;sim; 10-30 min time frame, is equally important but complicated by the tendency of bacterial adhesion to strengthen within minutes of initial capture. This study uses Staphylococcus aureus as a model bacterium to demonstrate the general strategy of clustering adhesive surface functionality (at length scales smaller than the bacteria themselves) on otherwise nonadhesive surfaces to capture and retain bacteria (easy come) while limiting the progressive strengthening of adhesion. The loose attachment facilitates bacteria removal by moderate shearing flow (easy go). This strategy is demonstrated using surfaces containing sparsely and randomly arranged immobilized amine-functionalized nanoparticles or poly-l-lysine chains, about 10 nm in size. The rest of the surface is backfilled with a nonadhesive polyethylene glycol (PEG) brush that, by itself, repels S. aureus. The nanoparticles or polymer chains cluster cationic functionality, providing small regions that attract negatively charged S. aureus cells. Compared with surfaces of nearly uniform cationic character where S. aureus adhesion quickly becomes strong (on a time scale less than 5 min), placement of cationic charge in small clusters retards or prevents processes that increase bacteria adhesion on a time scale of &amp;sim; 30 min, providing &amp;quot;easy go&amp;quot; surfaces.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fang, Bing</style></author><author><style face="normal" font="default" size="100%">Gon, Saugata</style></author><author><style face="normal" font="default" size="100%">Park, Myoung</style></author><author><style face="normal" font="default" size="100%">Kumar, Kushi-Nidhi</style></author><author><style face="normal" font="default" size="100%">Rotello, Vincent M</style></author><author><style face="normal" font="default" size="100%">Nusslein, Klaus</style></author><author><style face="normal" font="default" size="100%">Santore, Maria M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Bacterial adhesion on hybrid cationic nanoparticle-polymer brush surfaces: ionic strength tunes capture from monovalent to multivalent binding.</style></title><secondary-title><style face="normal" font="default" size="100%">Colloids Surf B Biointerfaces</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Colloids Surf B Biointerfaces</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Bacterial Adhesion</style></keyword><keyword><style  face="normal" font="default" size="100%">Cations</style></keyword><keyword><style  face="normal" font="default" size="100%">Nanoparticles</style></keyword><keyword><style  face="normal" font="default" size="100%">Osmolar Concentration</style></keyword><keyword><style  face="normal" font="default" size="100%">Polyethylene Glycols</style></keyword><keyword><style  face="normal" font="default" size="100%">Polylysine</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicon Dioxide</style></keyword><keyword><style  face="normal" font="default" size="100%">Staphylococcus aureus</style></keyword><keyword><style  face="normal" font="default" size="100%">Static Electricity</style></keyword><keyword><style  face="normal" font="default" size="100%">Surface Properties</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2011 Oct 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">87</style></volume><pages><style face="normal" font="default" size="100%">109-15</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This paper describes the creation of hybrid surfaces containing cationic nanoparticles and biocompatible PEG (polyethylene glycol) brushes that manipulate bacterial adhesion for potential diagnostic and implant applications. Here, ∼10 nm cationically functionalized gold nanoparticles are immobilized randomly on negative silica surfaces at tightly controlled surface loadings, and the remaining areas are functionalized with a hydrated PEG brush, using a graft copolymer of poly-l-lysine and PEG (PLL-PEG), containing 2000 molecular weight PEG chains and roughly 30% functionalization of the PLL. The cationic nanoparticles attract the negative surfaces of suspended Staphylococcus aureus bacteria while the PEG brush exerts a steric repulsion. With the nanoparticle and PEG brush heights on the same lengthscale, variations in ionic strength are demonstrated to profoundly influence the capture of S. aureus on these surfaces. For bacteria captured from gentle flow, a crossover from multivalent to univalent binding is demonstrated as the Debye length is increased from 1 to 4 nm. In the univalent regime, 1 um diameter spherical bacteria are captured and held by single nanoparticles. In the multivalent regime, there is an adhesion threshold in the surface density of nanoparticles needed for bacterial capture. The paper also documents an interesting effect concerning the relaxations in the PLL-PEG brush itself. For brushy surfaces containing no nanoparticles, bacterial adhesion persists on newly formed brushes, but is nearly eliminated after these brushes relax, at constant mass in buffer for 12h. Thus brushy relaxations increase biocompatibility.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/21640564?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kalasin, Surachate</style></author><author><style face="normal" font="default" size="100%">Dabkowski, Jeffrey</style></author><author><style face="normal" font="default" size="100%">Nüsslein, Klaus</style></author><author><style face="normal" font="default" size="100%">Santore, Maria M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The role of nano-scale heterogeneous electrostatic interactions in initial bacterial adhesion from flow: a case study with Staphylococcus aureus.</style></title><secondary-title><style face="normal" font="default" size="100%">Colloids Surf B Biointerfaces</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Colloids Surf B Biointerfaces</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Adsorption</style></keyword><keyword><style  face="normal" font="default" size="100%">Bacterial Adhesion</style></keyword><keyword><style  face="normal" font="default" size="100%">Methacrylates</style></keyword><keyword><style  face="normal" font="default" size="100%">Nylons</style></keyword><keyword><style  face="normal" font="default" size="100%">Particle Size</style></keyword><keyword><style  face="normal" font="default" size="100%">Serum Albumin, Bovine</style></keyword><keyword><style  face="normal" font="default" size="100%">Silicon Dioxide</style></keyword><keyword><style  face="normal" font="default" size="100%">Staphylococcus aureus</style></keyword><keyword><style  face="normal" font="default" size="100%">Static Electricity</style></keyword><keyword><style  face="normal" font="default" size="100%">Surface Properties</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Apr 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">76</style></volume><pages><style face="normal" font="default" size="100%">489-95</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study investigated the initial adhesion of Staphylococcus aureus from flowing buffer onto modified albumin films with the objective of probing the influence of electrostatic heterogeneity on bacterial adhesion. Electrostatic heterogeneity, on the lengthscale of 10-100 nm, was incorporated into the protein film through the irreversible random deposition of small amounts of polycation coils to produce isolated positive &quot;patches&quot; on the otherwise negative albumin surface before exposure to bacteria, which also possess a net negative surface charge. The system was benchmarked against an appropriate analog using 1 microm silica spheres and the same cationic patches on a silica substrate. Bacterial adhesion from flow was measured with the surface oriented vertically to eliminate gravitational forces between the bacteria and collector. In both systems, a threshold in the surface density of polycation patches needed for bacterial (or silica particle) capture indicated multivalent binding: multiple polycation patches were needed to adhere the bacteria (particles). The shifting of the threshold to greater patch concentrations at lower ionic strengths confirmed that the electrostatic interaction area (zone of influence) was a key factor in modulating the interactions. The role of the contact area in this manner is important because it enables a quantitative explanation of counterintuitive bacterial adhesion onto net negative surfaces. The study further revealed a hydrodynamic crossover from a regime where flow aids bacterial adhesion to one where flow impedes adhesion. An explanation is put forth in terms of the relative hydrodynamic and surface forces.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20074917?dopt=Abstract</style></custom1></record></records></xml>