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Xu Z, Gamble A, Niu WA, Smith MN, Sloan Siegrist M, Tuominen M, Santore MM. Contact Area and Deformation of Escherichia coli Cells Adhered on a Cationic Surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:6387-6398. [PMID: 37053037 PMCID: PMC10685399 DOI: 10.1021/acs.langmuir.3c00089] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
When bacteria adhere to surfaces, the chemical and mechanical character of the cell-substrate interface guides cell function and the development of microcolonies and biofilms. Alternately on bactericidal surfaces, intimate contact is critical to biofilm prevention. The direct study of the buried cell-substrate interfaces at the heart of these behaviors is hindered by the small bacterial cell size and inaccessibility of the contact region. Here, we present a total internal reflectance fluorescence depletion approach to measure the size of the cell-substrate contact region and quantify the gap separation and curvature near the contact zone, providing an assessment of the shapes of the near-surface undersides of adhered bacterial cells. Resolution of the gap height is about 10%, down to a few nanometers at contact. Using 1 and 2 μm silica spheres as calibration standards we report that, for flagella-free Escherichia coli (E. coli) adhering on a cationic poly-l-lysine layer, the cell-surface contact and apparent cell deformation vary with adsorbed cell configuration. Most cells adhere by their ends, achieving small contact areas of 0.15 μm2, corresponding to about 1-2% of the cell's surface. The altered Gaussian curvatures of end-adhered cells suggest the flattening of the envelope within the small contact region. When cells adhere by their sides, the contact area is larger, in the range 0.3-1.1 μm2 and comprising up to ∼12% of the cell's total surface. A region of sharper curvature, greater than that of the cells' original spherocylindrical shape, borders the flat contact region in cases of side-on or end-on cell adhesion, suggesting envelope stress. From the measured curvatures, precise stress distributions over the cell surface could be calculated in future studies that incorporate knowledge of envelope moduli. Overall the small contact areas of end-adhered cells may be a limiting factor for antimicrobial surfaces that kill on contact rather than releasing bactericide.
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Affiliation(s)
- Zhou Xu
- Department of Physics, University of Massachusetts, Amherst, MA 01003 USA
| | - Alexander Gamble
- Department of Plant and Soil Science, University of Massachusetts, Amherst, MA 01003 USA
| | - Wuqi Amy Niu
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, MA 01003 USA
| | - Morgan N. Smith
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, MA 01003 USA
| | - M. Sloan Siegrist
- Department of Microbiology, University of Massachusetts Amherst, MA 01003 USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA 01003 USA
| | - Mark Tuominen
- Department of Physics, University of Massachusetts, Amherst, MA 01003 USA
| | - Maria M. Santore
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, MA 01003 USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA 01003 USA
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Santore MM. Interplay of physico-chemical and mechanical bacteria-surface interactions with transport processes controls early biofilm growth: A review. Adv Colloid Interface Sci 2022; 304:102665. [PMID: 35468355 DOI: 10.1016/j.cis.2022.102665] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 11/01/2022]
Abstract
Biofilms initiate when bacteria encounter and are retained on surfaces. The surface orchestrates biofilm growth through direct physico-chemical and mechanical interactions with different structures on bacterial cells and, in turn, through its influence on cell-cell interactions. Individual cells respond directly to a surface through mechanical or chemical means, initiating "surface sensing" pathways that regulate gene expression, for instance producing extra cellular matrix or altering phenotypes. The surface can also physically direct the evolving colony morphology as cells divide and grow. In either case, the physico-chemistry of the surface influences cells and cell communities through mechanisms that involve additional factors. For instance the numbers of cells arriving on a surface from solution relative to the generation of new cells by division depends on adhesion and transport kinetics, affecting early colony density and composition. Separately, the forces experienced by adhering cells depend on hydrodynamics, gravity, and the relative stiffnesses and viscoelasticity of the cells and substrate materials, affecting mechanosensing pathways. Physical chemistry and surface functionality, along with interfacial mechanics also influence cell-surface friction and control colony morphology, in particular 2D and 3D shape. This review focuses on the current understanding of the mechanisms in which physico-chemical interactions, deriving from surface functionality, impact individual cells and cell community behavior through their coupling with other interfacial processes.
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Ma J, Li K, Gu S. Selective strategies for antibacterial regulation of nanomaterials. RSC Adv 2022; 12:4852-4864. [PMID: 35425473 PMCID: PMC8981418 DOI: 10.1039/d1ra08996j] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 01/25/2022] [Indexed: 12/14/2022] Open
Abstract
Recalcitrant bacterial infection, as a worldwide challenge, causes large problems for human health and is attracting great attention. The excessive antibiotic-dependent treatment of infections is prone to induce antibiotic resistance. A variety of unique nanomaterials provide an excellent toolkit for killing bacteria and preventing drug resistance. It is of great importance to summarize the design rules of nanomaterials for inhibiting the growth of pathogenic bacteria. We completed a review involving the strategies for regulating antibacterial nanomaterials. First, we discuss the antibacterial manipulation of nanomaterials, including the interaction between the nanomaterial and the bacteria, the damage of the bacterial structure, and the inactivation of biomolecules. Next, we identify six main factors for controlling the antibacterial activity of nanomaterials, including their element composition, size dimensions, surface charge, surface topography, shape selection and modification density. Every factor possesses a preferable standard for maximizing antibacterial activity, providing universal rules for antibacterial regulation of nanomaterials. We hope this comprehensive review will help researchers to precisely design and synthesize nanomaterials, developing intelligent antibacterial agents to address bacterial infections. This review builds universal design rules for the antibacterial regulation of nanomaterials.![]()
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Affiliation(s)
- Jinliang Ma
- College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, Henan 471023, China
- Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Kexin Li
- College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, Henan 471023, China
| | - Shaobin Gu
- College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, Henan 471023, China
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4
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Xu Z, Niu WA, Rivera SL, Tuominen MT, Siegrist MS, Santore MM. Surface Chemistry Guides the Orientations of Adhering E. coli Cells Captured from Flow. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:7720-7729. [PMID: 34125547 DOI: 10.1021/acs.langmuir.1c00764] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Motivated by observations of cell orientation at biofilm-substrate interfaces and reports that cell orientation and adhesion play important roles in biofilm evolution and function, we investigated the influence of surface chemistry on the orientation of Escherichia coli cells captured from flow onto surfaces that were cationic, hydrophobic, or anionic. We characterized the initial orientations of nonmotile cells captured from gentle shear relative to the surface and flow directions. The broad distribution of captured cell orientations observed on cationic surfaces suggests that rapid electrostatic attractions of cells to oppositely charged surfaces preserve the instantaneous orientations of cells as they rotate in the near-surface shearing flow. By contrast, on hydrophobic and anionic surfaces, cells were oriented slightly more in the plane of the surface and in the flow direction compared with that on the cationic surface. This suggests slower development of adhesion at hydrophobic and anionic surfaces, allowing cells to tip toward the surface as they adhere. Once cells were captured, the flow was increased by 20-fold. Cells did not reorient substantially on the cationic surface, suggesting a strong cell-surface bonding. By contrast, on hydrophobic and anionic surfaces, increased shear forced cells to tip toward the surface and align in the flow direction, a process that was reversible upon reducing the shear. These findings suggest mechanisms by which surface chemistry may play a role in the evolving structure and function of microbial communities.
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Affiliation(s)
- Zhou Xu
- Department of Physics, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Wuqi Amy Niu
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Sylvia L Rivera
- Department of Microbiology, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Mark T Tuominen
- Department of Physics, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - M Sloan Siegrist
- Department of Microbiology, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Maria M Santore
- Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
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5
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Bradford SA, Sasidharan S, Kim H, Gomez-Flores A, Li T, Shen C. Colloid Interaction Energies for Surfaces with Steric Effects and Incompressible and/or Compressible Roughness. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:1501-1510. [PMID: 33470105 DOI: 10.1021/acs.langmuir.0c03029] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Colloid aggregation and retention in the presence of macromolecular coatings (e.g., adsorbed polymers, surfactants, proteins, biological exudates, and humic materials) have previously been correlated with electric double layer interactions or repulsive steric interactions, but the underlying causes are not fully resolved. An interaction energy model that accounts for double layer, van der Waals, Born, and steric interactions as well as nanoscale roughness and charge heterogeneity on both surfaces was extended, and theoretical calculations were conducted to address this gap in knowledge. Macromolecular coatings may produce steric interactions in the model, but non-uniform or incomplete surface coverage may also create compressible nanoscale roughness with a charge that is different from the underlying surface. Model results reveal that compressible nanoscale roughness reduces the energy barrier height and the magnitude of the primary minimum at separation distances exterior to the adsorbed organic layer. The depth of the primary minimum initially alters (e.g., increases or decreases) at separation distances smaller than the adsorbed organic coating because of a decrease in the compressible roughness height and an increase in the roughness fraction. However, further decreases in the separation distance create strong steric repulsion that dominates the interaction energy profile and limits the colloid approach distance. Consequently, adsorbed organic coatings on colloids can create shallow primary minimum interactions adjacent to organic coatings that can explain enhanced stability and limited amounts of aggregation and retention that have commonly been observed. The approach outlined in this manuscript provides an improved tool that can be used to design adsorbed organic coatings for specific colloid applications or interpret experimental observations.
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Affiliation(s)
| | - Salini Sasidharan
- USDA, ARS, SAWS Unit, Davis, California 95616, United States
- Environmental Sciences Department, University of California, Riverside, California 92521, United States
| | - Hyunjung Kim
- Department of Mineral Resources and Energy Engineering, Jeonbuk National University, 664-14 Deokjin, Jeonju, Jeonbuk 54896, Republic of Korea
| | - Allan Gomez-Flores
- Department of Mineral Resources and Energy Engineering, Jeonbuk National University, 664-14 Deokjin, Jeonju, Jeonbuk 54896, Republic of Korea
| | - Tiantian Li
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Chongyang Shen
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
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Li T, Shen C, Wu S, Jin C, Bradford SA. Synergies of surface roughness and hydration on colloid detachment in saturated porous media: Column and atomic force microscopy studies. WATER RESEARCH 2020; 183:116068. [PMID: 32619803 DOI: 10.1016/j.watres.2020.116068] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 06/11/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
Saturated column experiments were conducted to systematically examine the influence of hydration on the detachment of nano- and micro-sized latex colloids (35 nm and 1 μm, respectively) from sand. The colloids were attached on the sand in primary minima (PM) using high ionic strength (IS) NaCl solutions. The PM were predicted to be shallower and located farther from sand surfaces with increasing IS due to the hydration force. Consequently, a greater amount of colloid detachment occurred in deionized water when the colloids were initially deposited at a higher IS. Atomic force microscopy (AFM) examinations showed that both nanoscale protruding asperities and large wedge-like valleys existed on the sand surface. The influence of these surface features on the interaction energies/forces was modeled by approximating the roughness as cosinoidal waves and two intersecting half planes, respectively. The PM were deep and attachment was irreversible at concave regions for all ISs, even if the hydration force was included. Conversely, colloids were weakly attached at protruding asperities due to a reduced PM depth, and thus were responsible for the detachment upon IS reduction. The AFM examinations confirmed that the adhesive forces were enhanced and reduced (or even completely eliminated) at concave and convex locations of sand surfaces, respectively. These results have important implications for surface cleaning and prediction of the transport and fate of hazardous colloids and colloid-associated contaminants in subsurface environments.
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Affiliation(s)
- Tiantian Li
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Chongyang Shen
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China.
| | - Sen Wu
- School of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, 300072, China
| | - Chao Jin
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, Guangdong, 510006, China
| | - Scott A Bradford
- USDA, ARS, U.S. Salinity Laboratory, Riverside, CA, 92507-4617, United States.
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7
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El-Kirat-Chatel S, Beaussart A, Mathelié-Guinlet M, Dufrêne YF. The importance of force in microbial cell adhesion. Curr Opin Colloid Interface Sci 2020. [DOI: 10.1016/j.cocis.2019.12.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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8
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Abstract
Microbial adhesion and biofilm formation are usually studied using molecular and cellular biology assays, optical and electron microscopy, or laminar flow chamber experiments. Today, atomic force microscopy (AFM) represents a valuable addition to these approaches, enabling the measurement of forces involved in microbial adhesion at the single-molecule level. In this minireview, we discuss recent discoveries made applying state-of-the-art AFM techniques to microbial specimens in order to understand the strength and dynamics of adhesive interactions. These studies shed new light on the molecular mechanisms of adhesion and demonstrate an intimate relationship between force and function in microbial adhesins.
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9
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Yang Y, Bogler A, Ronen Z, Oron G, Herzberg M, Bernstein R. Initial Deposition and Pioneering Colonization on Polymeric Membranes of Anaerobes Isolated from an Anaerobic Membrane Bioreactor (AnMBR). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:5832-5842. [PMID: 32289225 DOI: 10.1021/acs.est.9b06763] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Membrane biofouling constitutes a great challenge in anaerobic membrane bioreactor (AnMBR). Here, we studied the initial deposition of anaerobes, the first step in biofilm formation, with a consortium isolated from an AnMBR on membranes with different surface properties and under two shear rate conditions without filtration. We found that the cell transfer coefficient, calculated from the initial deposition experiments, was similar under the two shear rates for the hydrophobic membranes, but much higher under low shear rate and much lower under high shear rate, for the hydrophilic membrane. The cell transfer coefficient measured under filtration mode and at a higher shear rate showed a similar trend. The pioneer bacteria and archaea (without filtration) were identified by next-generation sequencing. The results showed that the selective force for the dissimilarity of the pioneer bacterial and archaeal diversity was the shear rate and the membrane surface properties, respectively. However, statistical analyses revealed minor changes in the pioneer bacteria (class level) and archaea (order level) populations under the various conditions. These results shed light on the first step of biofilm formation on the membranes in AnMBRs and emphasize the importance of hydrodynamic shear and membrane surface properties on the initially deposited anaerobes.
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Affiliation(s)
- Yang Yang
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boker 8499000, Israel
| | - Anne Bogler
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boker 8499000, Israel
| | - Zeev Ronen
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boker 8499000, Israel
| | - Gideon Oron
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boker 8499000, Israel
| | - Moshe Herzberg
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boker 8499000, Israel
| | - Roy Bernstein
- The Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sde Boker 8499000, Israel
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Mathelié-Guinlet M, Viela F, Viljoen A, Dehullu J, Dufrêne YF. Single-molecule atomic force microscopy studies of microbial pathogens. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2019. [DOI: 10.1016/j.cobme.2019.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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11
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Wu X, Lai T, Jiang J, Ma Y, Tao G, Liu F, Li N. An on-site bacterial detection strategy based on broad-spectrum antibacterial ε-polylysine functionalized magnetic nanoparticles combined with a portable fluorometer. Mikrochim Acta 2019; 186:526. [PMID: 31292779 DOI: 10.1007/s00604-019-3632-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 06/21/2019] [Indexed: 11/25/2022]
Abstract
A sensitive on-site bacterial detection strategy is presented that integrates the broad-spectrum capturing feature of ε-polylysine-functionalized magnetic nanoparticles with an in-house built portable fluorometer. Based on the electrostatic interaction, the functionalized magnetic nanoparticles (ε-PL-MNPs) were prepared for Gram-positive and Gram-negative bacterial separation and subsequent viable release. ε-PL-MNPs show a broad reactivity towards bacteria with the high capture efficiency from real-world sample media. They also enable controlled viable bacterial release with pH adjustment. Detection of bacteria is based on a combination of broad-spectrum capture with colorimetric and fluorimetric immunoassays. A portable fluorometer is built to enhance the applicability for sensitive on-site detection. A limit of detection of 98 CFU·mL-1 is achieved that is comparable to that of a known spectrofluorometric method for E. coli DH5α. Graphical abstract Schematic presentation of bacterial capture using cationic polymer functionalized magnetic nanoparticles and general fluorometric immunoassay with portable fluorometer. The limit of detection is 98 CFU·mL-1 for E. coli DH5α.
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Affiliation(s)
- Xi Wu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Tiancheng Lai
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Jiezhang Jiang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Yurou Ma
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Guangyu Tao
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Feng Liu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Na Li
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
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12
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Wang H, Zhang W, Zeng S, Shen C, Jin C, Huang Y. Interactions between nanoparticles and fractal surfaces. WATER RESEARCH 2019; 151:296-309. [PMID: 30616042 DOI: 10.1016/j.watres.2018.12.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 12/13/2018] [Accepted: 12/15/2018] [Indexed: 06/09/2023]
Abstract
This study evaluated attachment of a 30-nm nanoparticle to and detachment from fractal surfaces by calculating Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction energies in three-dimensional space using the surface element integration technique. The fractal surfaces were generated using the Weierstass-Mandelbrot function with varying values of fractal dimension D (2.3 ≤ D ≤ 2.7) and fractal roughness G (0.000136 ≤ G ≤ 0.136). Results show that maximum energy barrier is reduced at peak areas of a fractal surface, and hence attachment in primary minima is favored. Some nanoparticles attached in primary minima at the peak areas can be detached by decreasing ionic strength (IS) due to monotonic decrease of interaction energy with increasing separation distance at low ISs. While the attachment in primary minima at valley areas is irreversible to IS reduction, the attachment is inhibited due to enhanced maximum energy barrier at these areas. A nonmonotonic variation of attachment efficiency in primary minimum (AEPM) with IS is present at high fractal dimension (D ≥ 2.4) or low fractal roughness (G < 0.00136), whereas the AEPM decreases monotonically with decreasing IS at low fractal dimension (D < 2.4) or high fractal roughness (G ≥ 0.00136). The AEPM decreases monotonically with increasing D or decreasing G at ISs from 1 mM to 200 mM. The decrease of AEPM with D or G is much slower at 10 mM compared to other ISs. These theoretical findings can explain various experimental observations in the literature, and can have important utility to development of water filtration techniques in engineered systems and to assessment of environmental risks of nanoparticles.
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Affiliation(s)
- Hong Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Wei Zhang
- Department of Plant, Soil and Microbial Sciences, and Environmental Science and Policy Program, Michigan State University, East Lansing, MI, 48824, United States
| | - Saiqi Zeng
- Department of Plant and Soil Sciences, University of Delaware, Newark, DE, 19716, United States
| | - Chongyang Shen
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China.
| | - Chao Jin
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, Guangdong, 510006, China
| | - Yuanfang Huang
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China.
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13
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Xie Y, Li J, Bu D, Xie X, He X, Wang L, Zhou Z. Nepenthes-inspired multifunctional nanoblades with mechanical bactericidal, self-cleaning and insect anti-adhesive characteristics. RSC Adv 2019; 9:27904-27910. [PMID: 35530501 PMCID: PMC9071107 DOI: 10.1039/c9ra05198h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 08/24/2019] [Indexed: 01/22/2023] Open
Abstract
In order to reduce the widespread threat of bacterial pathogen diseases, mechanical bactericidal surfaces have been widely reported. However, few of these nanostructured surfaces were investigated from a sustainable perspective. In this study, we have prepared, inspired by the slippery zone of Nepenthes, a multifunctional nanostructured surface with mechanical bactericidal, self-cleaning and insect anti-adhesive characteristics. First, a nanoblade-like surface made of Zn–Al layered double hydroxides was prepared for achieving faster bactericidal rate and wider bactericidal spectrum (2.10 × 104 CFU cm−2 min−1 against Escherichia coli and 1.78 × 103 CFU cm−2 min−1 against Staphylococcus aureus). Then the self-cleaning and insect anti-adhesive properties were tested on the fluorosilane-modified nanoblades, leaving little cell debris remaining on the surface even after 4 continuous bactericidal experiments, and showing a slippery surface for ants to slide down in 3 s. This study not only discovers a new nature-inspired mechanical bactericidal nanotopography, but also provides a facile approach to incorporate multiple functions into the nanostructured surface for practical antibacterial applications. Inspired by the slippery zone of Nepenthes, we fabricated a multifunctional blade like nanostructured surface with the same mechanical bactericidal, self-cleaning and insect anti-adhesive characteristics.![]()
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Affiliation(s)
- Yuan Xie
- School of Materials Science and Engineering
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education)
- Southwest Jiaotong University
- Chengdu 610031
- China
| | - Jinyang Li
- School of Materials Science and Engineering
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education)
- Southwest Jiaotong University
- Chengdu 610031
- China
| | - Daqin Bu
- School of Materials Science and Engineering
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education)
- Southwest Jiaotong University
- Chengdu 610031
- China
| | - Xuedong Xie
- School of Materials Science and Engineering
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education)
- Southwest Jiaotong University
- Chengdu 610031
- China
| | - Xiaolong He
- National Laboratory of Biomacromolecules
- Institute of Biophysics
- Chinese Academy of Sciences
- Beijing 100101
- China
| | - Li Wang
- Qian Xuesen Laboratory of Space Technology
- Beijing 100094
- China
| | - Zuowan Zhou
- School of Materials Science and Engineering
- Key Laboratory of Advanced Technologies of Materials (Ministry of Education)
- Southwest Jiaotong University
- Chengdu 610031
- China
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14
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Carniello V, Peterson BW, van der Mei HC, Busscher HJ. Physico-chemistry from initial bacterial adhesion to surface-programmed biofilm growth. Adv Colloid Interface Sci 2018; 261:1-14. [PMID: 30376953 DOI: 10.1016/j.cis.2018.10.005] [Citation(s) in RCA: 170] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/08/2018] [Accepted: 10/22/2018] [Indexed: 02/07/2023]
Abstract
Biofilm formation is initiated by adhesion of individual bacteria to a surface. However, surface adhesion alone is not sufficient to form the complex community architecture of a biofilm. Surface-sensing creates bacterial awareness of their adhering state on the surface and is essential to initiate the phenotypic and genotypic changes that characterize the transition from initial bacterial adhesion to a biofilm. Physico-chemistry has been frequently applied to explain initial bacterial adhesion phenomena, including bacterial mass transport, role of substratum surface properties in initial adhesion and the transition from reversible to irreversible adhesion. However, also emergent biofilm properties, such as production of extracellular-polymeric-substances (EPS), can be surface-programmed. This review presents a four-step, comprehensive description of the role of physico-chemistry from initial bacterial adhesion to surface-programmed biofilm growth: (1) bacterial mass transport towards a surface, (2) reversible bacterial adhesion and (3) transition to irreversible adhesion and (4) cell wall deformation and associated emergent properties. Bacterial transport mostly occurs from sedimentation or convective-diffusion, while initial bacterial adhesion can be described by surface thermodynamic and Derjaguin-Landau-Verwey-Overbeek (DLVO)-analyses, considering bacteria as smooth, inert colloidal particles. DLVO-analyses however, require precise indication of the bacterial cell surface, which is impossible due to the presence of bacterial surface tethers, creating a multi-scale roughness that impedes proper definition of the interaction distance in DLVO-analyses. Application of surface thermodynamics is also difficult, because initial bacterial adhesion is only an equilibrium phenomenon for a short period of time, when bacteria are attached to a substratum surface through few surface tethers. Physico-chemical bond-strengthening occurs in several minutes leading to irreversible adhesion due to progressive removal of interfacial water, conformational changes in cell surface proteins, re-orientation of bacteria on a surface and the progressive involvement of more tethers in adhesion. After initial bond-strengthening, adhesion forces arising from a substratum surface cause nanoscopic deformation of the bacterial cell wall against the elasticity of the rigid peptidoglycan layer positioned in the cell wall and the intracellular pressure of the cytoplasm. Cell wall deformation not only increases the contact area with a substratum surface, presenting another physico-chemical bond-strengthening mechanism, but is also accompanied by membrane surface tension changes. Membrane-located sensor molecules subsequently react to control emergent phenotypic and genotypic properties in biofilms, most notably adhesion-associated ones like EPS production. Moreover, also bacterial efflux pump systems may be activated or mechano-sensitive channels may be opened upon adhesion-induced cell wall deformation. The physico-chemical properties of the substratum surface thus control the response of initially adhering bacteria and through excretion of autoinducer molecules extend the awareness of their adhering state to other biofilm inhabitants who subsequently respond with similar emergent properties. Herewith, physico-chemistry is not only involved in initial bacterial adhesion to surfaces but also in what we here propose to call "surface-programmed" biofilm growth. This conclusion is pivotal for the development of new strategies to control biofilm formation on substratum surfaces, that have hitherto been largely confined to the initial bacterial adhesion phenomena.
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15
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Khan M, Wu Z, Mao S, Shah SNA, Lin JM. Controlled grafted poly(quaternized-4-vinylpyridine-co-acrylic acid) brushes attract bacteria for effective antimicrobial surfaces. J Mater Chem B 2018; 6:3782-3791. [DOI: 10.1039/c8tb00702k] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The substrates were coated with P(Q4VP-co-AA) brushes and adsorbed GA to attract, kill and release microbes.
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Affiliation(s)
- Mashooq Khan
- Department of Chemistry
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology
- Tsinghua University
- Beijing
| | - Zengnan Wu
- Department of Chemistry
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology
- Tsinghua University
- Beijing
| | - Sifeng Mao
- Department of Chemistry
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology
- Tsinghua University
- Beijing
| | - Syed Niaz Ali Shah
- Department of Chemistry
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology
- Tsinghua University
- Beijing
| | - Jin-Ming Lin
- Department of Chemistry
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology
- Tsinghua University
- Beijing
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16
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Ma K, Gong L, Cai X, Huang P, Cai J, Huang D, Jiang T. A green single-step procedure to synthesize Ag-containing nanocomposite coatings with low cytotoxicity and efficient antibacterial properties. Int J Nanomedicine 2017; 12:3665-3679. [PMID: 28553106 PMCID: PMC5439938 DOI: 10.2147/ijn.s130857] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Implant-associated infections still pose a serious threat leading to several complications. This study reported an environmentally benign Ag-containing nanocomposite coating with efficient antibacterial property fabricated on the metal implant via electrophoretic deposition (EPD). In such coatings, Ag2O/AgCl mixed with chitosan/gelatin (CS/G) polymers work together to exert the antibacterial property which could act as an alternative to traditional Ag nanoparticles. Scanning electron microscopy images showed the shuttle fiber-like morphology distributed lamellarly and some nanoparticles carved uniformly into the cross section. Transmission electron microscopy results revealed a core-shell-like structure of the released nanoparticles in experimental groups. The Ag-containing coatings exhibited strong antibacterial properties against Staphylococcus aureus strains and Escherichia coli strains. Meanwhile, the CCK-8 tests showed that after assembling with chitosan and gelatin polymers, the cytotoxicity of Ag was largely decreased. In addition, such coatings also exhibited strong bond strength with metal substrates and good degradable properties. Therefore, such Ag-containing CS/G coatings fabricated via EPD may be a promising candidate to be administrated in controlling the implant-associated infections.
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Affiliation(s)
- Kena Ma
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology.,Department of Prosthodontics, Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China
| | - Lingling Gong
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology
| | - Xinjie Cai
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology.,Department of Prosthodontics, Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China
| | - Pin Huang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology
| | - Jing Cai
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology
| | - Dan Huang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology
| | - Tao Jiang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology.,Department of Prosthodontics, Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China
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17
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Hizal F, Choi CH, Busscher HJ, van der Mei HC. Staphylococcal Adhesion, Detachment and Transmission on Nanopillared Si Surfaces. ACS APPLIED MATERIALS & INTERFACES 2016; 8:30430-30439. [PMID: 27750009 DOI: 10.1021/acsami.6b09437] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Nanostructured surfaces are extensively considered with respect to their potential impact on bacterial adhesion from aqueous suspensions or air, but in real-life bacteria are often transmitted between surfaces. Mechanistically, transmission involves detachment of adhering bacteria from a donor and adhesion to a receiver surface, controlled by the relative values of the adhesion forces exerted by both surfaces. We here relate staphylococcal adhesion, detachment and transmission to, from, and between smooth and nanopillared-Si surfaces with staphylococcal adhesion forces. Nanopillared-Si surfaces were prepared with pillar-to-pillar distances of 200, 400, and 800 nm. On smooth surfaces, staphylococcal adhesion forces, measured using bacterial-probe Atomic-Force-Microscopy, amounted to 4.4-6.8 and 1.8-2.1 nN (depending on the AFM-loading force) for extracellular-polymeric-substances (EPS) producing and non-EPS producing strains, respectively. Accordingly the EPS producing strain adhered in higher numbers than the non-EPS producing strain. Fractional adhesion forces on nanopillared-Si surfaces relative to the smooth surface ranged from 0.30 to 0.95, depending on AFM-loading force, strain and pillar-to-pillar distance. However, for each strain, the number of adhering bacteria remained similar on all nanopillared surfaces. Detachment of adhering staphylococci decreased significantly with increasing adhesion forces, while staphylococcal transmission to a receiver surface also decreased with increasing adhesion force exerted by the donor. In addition, the strain with ability to produce EPS was killed in high percentages and induced to produce EPS during transmission on nanopillared-Si surfaces, presumably by high local cell-wall stresses. This must be accounted for in applications of nanostructured surfaces: whereas killing may be favorable, EPS production may reduce antimicrobial efficacy.
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Affiliation(s)
- Ferdi Hizal
- Department of Mechanical Engineering, Stevens Institute of Technology , Castle Point on Hudson, Hoboken, New Jersey 07030, United States
- University of Groningen and University Medical Center Groningen , Department of Biomedical Engineering (FB40), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Chang-Hwan Choi
- Department of Mechanical Engineering, Stevens Institute of Technology , Castle Point on Hudson, Hoboken, New Jersey 07030, United States
| | - Henk J Busscher
- University of Groningen and University Medical Center Groningen , Department of Biomedical Engineering (FB40), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Henny C van der Mei
- University of Groningen and University Medical Center Groningen , Department of Biomedical Engineering (FB40), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
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18
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Huo S, Jiang Y, Gupta A, Jiang Z, Landis R, Hou S, Liang XJ, Rotello VM. Fully Zwitterionic Nanoparticle Antimicrobial Agents through Tuning of Core Size and Ligand Structure. ACS NANO 2016; 10:8732-7. [PMID: 27622756 PMCID: PMC5848071 DOI: 10.1021/acsnano.6b04207] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Zwitterionic nanoparticles are generally considered nontoxic and noninteracting. Here, we report effective and selective antimicrobial activity of zwitterionic gold nanoparticles (AuNP) through modulation NP size and surface charge orientation. Using a set of 2, 4, and 6 nm core AuNPs, increasing particle size increased antimicrobial efficiency through bacterial membrane disruption. Further improvement was observed through control of the ligand structure, generating antimicrobial particles with low hemolytic activity and demonstrating the importance of size and surface structure in dictating the bioactivity properties of nanomaterials.
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Affiliation(s)
- Shuaidong Huo
- Department of Chemistry, University of Massachusetts-Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA
- CAS Center of Excellence for Nanoscience, National Center for Nanoscience and Technology, First North Road, Zhongguancun, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Ying Jiang
- Department of Chemistry, University of Massachusetts-Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA
| | - Akash Gupta
- Department of Chemistry, University of Massachusetts-Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA
| | - Ziwen Jiang
- Department of Chemistry, University of Massachusetts-Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA
| | - Ryan Landis
- Department of Chemistry, University of Massachusetts-Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA
| | - Singyuk Hou
- Department of Chemistry, University of Massachusetts-Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA
| | - Xing-Jie Liang
- CAS Center of Excellence for Nanoscience, National Center for Nanoscience and Technology, First North Road, Zhongguancun, Beijing 100190, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- Address correspondence to and
| | - Vincent M. Rotello
- Department of Chemistry, University of Massachusetts-Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA
- Address correspondence to and
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19
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Huang K, Chen J, Nugen SR, Goddard JM. Hybrid Antifouling and Antimicrobial Coatings Prepared by Electroless Co-Deposition of Fluoropolymer and Cationic Silica Nanoparticles on Stainless Steel: Efficacy against Listeria monocytogenes. ACS APPLIED MATERIALS & INTERFACES 2016; 8:15926-36. [PMID: 27268033 DOI: 10.1021/acsami.6b04187] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Controlling formation, establishment, and proliferation of microbial biofilms on surfaces is critical for ensuring public safety. Herein, we report on the synthesis of antimicrobial nanoparticles and their co-deposition along with fluorinated nanoparticles during electroless nickel plating of stainless steel. Plating bath composition is optimized to ensure sufficiently low surface energy to resist fouling and microbial adhesion as well as to exert significant (>99.99% reduction) antimicrobial activity against Listeria monocytogenes. The resulting coatings present hybrid antifouling and antimicrobial character, can be applied onto stainless steel, and do not rely on leaching or migration of the antimicrobial nanoparticles to be effective. Such coatings can support reducing public health issues related to microbial cross-contamination in areas such as food processing, hospitals, and water purification.
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Affiliation(s)
- Kang Huang
- Department of Food Science, University of Massachusetts , 102 Holdsworth Way, Amherst, Massachusetts 01003, United States
| | - Juhong Chen
- Department of Food Science, University of Massachusetts , 102 Holdsworth Way, Amherst, Massachusetts 01003, United States
| | - Sam R Nugen
- Department of Food Science, University of Massachusetts , 102 Holdsworth Way, Amherst, Massachusetts 01003, United States
| | - Julie M Goddard
- Department of Food Science, University of Massachusetts , 102 Holdsworth Way, Amherst, Massachusetts 01003, United States
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20
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Dalier F, Eghiaian F, Scheuring S, Marie E, Tribet C. Temperature-Switchable Control of Ligand Display on Adlayers of Mixed Poly(lysine)-g-(PEO) and Poly(lysine)-g-(ligand-modified poly-N-isopropylacrylamide). Biomacromolecules 2016; 17:1727-36. [DOI: 10.1021/acs.biomac.6b00136] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- F. Dalier
- Ecole Normale
Supérieure-PSL Research University, Dpt Chimie, Sorbonne Universités
- UPMC Univ. Paris 06, CNRS UMR 8640, 24 rue Lhomond, 75005 Paris, France
| | - F. Eghiaian
- U1006 INSERM,
Aix-Marseille Université, Parc Scientifique et Technologique
de Luminy, 163 av. de Luminy, 13009 Marseille, France
| | - S. Scheuring
- U1006 INSERM,
Aix-Marseille Université, Parc Scientifique et Technologique
de Luminy, 163 av. de Luminy, 13009 Marseille, France
| | - E. Marie
- Ecole Normale
Supérieure-PSL Research University, Dpt Chimie, Sorbonne Universités
- UPMC Univ. Paris 06, CNRS UMR 8640, 24 rue Lhomond, 75005 Paris, France
| | - C. Tribet
- Ecole Normale
Supérieure-PSL Research University, Dpt Chimie, Sorbonne Universités
- UPMC Univ. Paris 06, CNRS UMR 8640, 24 rue Lhomond, 75005 Paris, France
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21
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Abadeer NS, Fülöp G, Chen S, Käll M, Murphy CJ. Interactions of Bacterial Lipopolysaccharides with Gold Nanorod Surfaces Investigated by Refractometric Sensing. ACS APPLIED MATERIALS & INTERFACES 2015; 7:24915-24925. [PMID: 26488238 DOI: 10.1021/acsami.5b08440] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The interface between nanoparticles and bacterial surfaces is of great interest for applications in nanomedicine and food safety. Here, we demonstrate that interactions between gold nanorods and bacterial surface molecules are governed by the nanoparticle surface coating. Polymer-coated gold nanorod substrates are exposed to lipopolysaccharides extracted from Pseudomonas aeruginosa, Salmonella enterica and Escherichia coli, and attachment is monitored using localized surface plasmon resonance refractometric sensing. The number of lipopolysaccharide molecules attached per nanorod is calculated from the shift in the plasmon maximum, which results from the change in refractive index after analyte binding. Colloidal gold nanorods in water are also incubated with lipopolysaccharides to demonstrate the effect of lipopolysaccharide concentration on plasmon shift, ζ-potential, and association constant. Both gold nanorod surface charge and surface chemistry affect gold nanorod-lipopolysaccharide interactions. In general, anionic lipopolysaccharides was found to attach more effectively to cationic gold nanorods than to neutral or anionic gold nanorods. Some variation in lipopolysaccharide attachment is also observed between the three strains studied, demonstrating the potential complexity of bacteria-nanoparticle interactions.
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Affiliation(s)
- Nardine S Abadeer
- Department of Chemistry, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
| | - Gergő Fülöp
- Department of Applied Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden
| | - Si Chen
- Department of Applied Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden
| | - Mikael Käll
- Department of Applied Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden
| | - Catherine J Murphy
- Department of Chemistry, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
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22
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Xiong X, Wu Z, Yu Q, Xue L, Du J, Chen H. Reversible Bacterial Adhesion on Mixed Poly(dimethylaminoethyl methacrylate)/Poly(acrylamidophenyl boronic acid) Brush Surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:12054-12060. [PMID: 26509287 DOI: 10.1021/acs.langmuir.5b02002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A simple and versatile method for the preparation of surfaces to control bacterial adhesion is described. Substrates were first treated with two catechol-based polymerization initiators, one for thermal initiation and one for visible-light photoinitiation. Graft polymerization in sequence of dimethylaminoethyl methacrylate (DMAEMA) and 3-acrylamidebenzene boronic acid (BA) from the surface-bound initiators to form mixed polymer brushes on the substrate was then carried out. The PDMAEMA grafts were thermally initiated and the PBA grafts were visible-light-photoinitiated. Gold, poly(vinyl chloride) (PVC), and poly(dimethylsiloxane) (PDMS) were used as model substrates. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), and ellipsometry analysis confirmed the successful grafting of PDMAEMA/PBA mixed brushes. We demonstrated that the resulting surfaces showed charge-reversal properties in response to change of pH. The transition in surface charge at a specific pH allowed the surface to be reversibly switched from bacteria-adhesive to bacteria-resistant. At pH 4.5, below the isoelectric points (IEP, pH 5.3) of the mixed brushes, the surfaces are positively charged and the negatively charged Gram-positive S. aureus adheres at high density (2.6 × 10(6) cells/cm(2)) due to attractive electrostatic interactions. Subsequently, upon increasing the pH to 9.0 to give negatively charged polymer brush surface, ∼90% of the adherent bacteria are released from the surface, presumably due to repulsive electrostatic interactions. This approach provides a simple method for the preparation of surfaces on which bacterial adhesion can be controlled and is applicable to a wide variety of substrates.
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Affiliation(s)
- Xinhong Xiong
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren-ai Road, Suzhou 215123, P. R. China
| | - Zhaoqiang Wu
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren-ai Road, Suzhou 215123, P. R. China
| | - Qian Yu
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren-ai Road, Suzhou 215123, P. R. China
| | - Lulu Xue
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren-ai Road, Suzhou 215123, P. R. China
| | - Jun Du
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren-ai Road, Suzhou 215123, P. R. China
| | - Hong Chen
- Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University , 199 Ren-ai Road, Suzhou 215123, P. R. China
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23
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Louzao I, Sui C, Winzer K, Fernandez-Trillo F, Alexander C. Cationic polymer mediated bacterial clustering: Cell-adhesive properties of homo- and copolymers. Eur J Pharm Biopharm 2015; 95:47-62. [DOI: 10.1016/j.ejpb.2015.05.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 05/15/2015] [Accepted: 05/26/2015] [Indexed: 11/16/2022]
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Zhu Z, Wang J, Lopez AI, Yu F, Huang Y, Kumar A, Li S, Zhang L, Cai C. Surfaces Presenting α-Phenyl Mannoside Derivatives Enable Formation of Stable, High Coverage, Non-pathogenic Escherichia coli Biofilms against Pathogen Colonization. Biomater Sci 2015; 3:781-880. [PMID: 26029359 PMCID: PMC4443871 DOI: 10.1039/c5bm00076a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Prevention of pathogenic colonization on medical devices over a long period of time remains a great challenge, especially in a high-nutrient environment that accelerates production of biomass leading to biofouling of the device. Since biofouling and the subsequent pathogen colonization is eventually inevitable, a new strategy using non-pathogenic bacteria as living guards against pathogenic colonization on medical devices has attracted increasing interest. Crucial to the success of this strategy is to pre-establish a high coverage and stable biofilm of benign bacteria on the surface. Silicone elastomers are one of the most widely used materials in biomedical devices. In this work, we modified silicone surfaces to promote formation of high coverage and stable biofilms by a non-pathogenic Escherichia coli strain 83972 with type 1 fimbriae (fim+) to interfere the colonization of an aggressive biofilm-forming, uropathogenic Enterococcus faecalis. Although it is well known that mannoside surfaces promote the initial adherence of fim+ E. coli through binding to the FimH receptor at the tip of the type 1 fimbriae, it is not clear whether the fast initial adherence could lead to a high coverage and stable protective biofilm. To explore the role of mannoside ligands, we synthesized a series of alkyl and aryl mannosides varied in structure and immobilized them on silicone surfaces pre-coated with poly(amidoamine) (PAMAM) dendrimer. We found that stable and densely packed benign E. coli biofilms were formed on the surfaces presenting biphenyl mannoside with the highest initial adherence of fim+ E. coli. These non-pathogenic biofilms prevented the colonization of E. faecalis for 11 days at a high concentration (108 CFU mL-1, 100,000 times above the diagnostic threshold for urinary tract infection) in the nutrient-rich Lysogeny Broth (LB) media. The result shows a correlation among the initial adherence of fim+ E. coli 83972, the coverage and long-term stability of the resultant biofilms, as well as their efficiency for preventing the pathogen colonization.
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Affiliation(s)
- Zhiling Zhu
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
| | - Jun Wang
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
| | - Analette I. Lopez
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
| | - Fei Yu
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
| | - Yongkai Huang
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
| | - Amit Kumar
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
| | - Siheng Li
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
| | - Lijuan Zhang
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, P R China
| | - Chengzhi Cai
- 112 Fleming Building, Department of Chemistry, University of Houston, Houston, Texas, 77204, USA. Fax: +1-713-743-2709; Tel: +1-713-743-2710
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25
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Fang B, Gon S, Nüsslein K, Santore MM. Surfaces for competitive selective bacterial capture from protein solutions. ACS APPLIED MATERIALS & INTERFACES 2015; 7:10275-10282. [PMID: 25955769 DOI: 10.1021/acsami.5b00864] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Active surfaces that form the basis for bacterial sensors for threat detection, food safety, or certain diagnostic applications rely on bacterial adhesion. However, bacteria capture from complex fluids on the active surfaces can be reduced by the competing adsorption of proteins and other large molecules. Such adsorption can also interfere with device performance. As a result, multiple upstream processing steps are frequently employed to separate macromolecules from any cells, which remain in the buffer. Here, we present an economical approach to capture bacteria, without competitive adsorption by proteins, on engineered surfaces that do not employ biomolecular recognition, antibodies, or other molecules with engineered sequences. The surfaces are based on polyethylene glycol (PEG) brushes that, on their own, repel both proteins and bacteria. These PEG brushes backfill the surface around sparsely adsorbed cationic polymer coils (here, poly-L-lysine (PLL)). The PLL coils are effectively embedded within the brush and produce locally cationic nanoscale regions that attract negatively charged regions of proteins or cells against the steric background repulsion from the PEG brush. By carefully designing the surfaces to include just enough PLL to capture bacteria, but not enough to capture proteins, we achieve sharp selectivity where S. aureus is captured from albumin- or fibrinogen-containing solutions, but free albumin or fibrinogen molecules are rejected from the surface. Bacterial adhesion on these surfaces is not reduced by competitive protein adsorption, in contrast to performance of more uniformly cationic surfaces. Also, protein adsorption to the bacteria does not interfere with capture, at least for the case of S. aureus, to which fibrinogen binds through a specific receptor.
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Affiliation(s)
- Bing Fang
- †Department of Polymer Science and Engineering, ‡Department of Chemical Engineering, and §Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Saugata Gon
- †Department of Polymer Science and Engineering, ‡Department of Chemical Engineering, and §Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Klaus Nüsslein
- †Department of Polymer Science and Engineering, ‡Department of Chemical Engineering, and §Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Maria M Santore
- †Department of Polymer Science and Engineering, ‡Department of Chemical Engineering, and §Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003, United States
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Bastarrachea LJ, Goddard JM. Antimicrobial coatings with dual cationic and N-halamine character: characterization and biocidal efficacy. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:4243-4251. [PMID: 25871333 DOI: 10.1021/acs.jafc.5b00445] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A method to prepare an antimicrobial coating for food-handling materials is reported. Alternating layers of branched polyethylenimine and styrene maleic anhydride copolymer were applied onto the surface of polypropylene. The resulting coatings had low surface energy and presented enhanced antimicrobial character due to the presence of both cationic and N-halamine forming structures. In its unchlorinated form, the coating inactivated Listeria monocytogenes by ∼3 logarithmic cycles. In the form of N-halamines >5 logarithmic cycles were reached. Microbial inactivation kinetics showed a Weibullian behavior when the coating was unchlorinated and a sigmoidal behavior when chlorinated. Microscopy confirmed that the reduction in the microbial load was due to biocidal effects of the coating and not bacterial adhesion onto the modified surface. The modified surface was able to be repeatedly rechlorinated. Such rechargeable antimicrobial coatings may support improving food safety by reducing cross-contamination of microorganisms from food-processing equipment.
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Affiliation(s)
- Luis J Bastarrachea
- Department of Food Science, University of Massachusetts, 102 Holdsworth Way, Amherst, Massachusetts 01003, United States
| | - Julie M Goddard
- Department of Food Science, University of Massachusetts, 102 Holdsworth Way, Amherst, Massachusetts 01003, United States
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27
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Bastarrachea LJ, Denis-Rohr A, Goddard JM. Antimicrobial Food Equipment Coatings: Applications and Challenges. Annu Rev Food Sci Technol 2015; 6:97-118. [DOI: 10.1146/annurev-food-022814-015453] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Luis J. Bastarrachea
- Department of Food Science, University of Massachusetts Amherst, Amherst, Massachusetts 01003;
| | - Anna Denis-Rohr
- Department of Food Science, University of Massachusetts Amherst, Amherst, Massachusetts 01003;
| | - Julie M. Goddard
- Department of Food Science, University of Massachusetts Amherst, Amherst, Massachusetts 01003;
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28
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Huang D, Yang G, Feng X, Lai X, Zhao P. Triazole-stabilized gold and related noble metal nanoparticles for 4-nitrophenol reduction. NEW J CHEM 2015. [DOI: 10.1039/c5nj00673b] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The preparation of N-substituted triazole–polyethylene glycol-stabilized metal nanoparticles and their high catalytic activities for 4-nitrophenol reduction.
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Affiliation(s)
- Deshun Huang
- Nano Chemistry Group
- Science and Technology on Surface Physics and Chemistry Laboratory
- Mianyang 621907
- China
| | - Guiying Yang
- Nano Chemistry Group
- Science and Technology on Surface Physics and Chemistry Laboratory
- Mianyang 621907
- China
- College of Materials Science and Engineering
| | - Xingwen Feng
- Nano Chemistry Group
- Science and Technology on Surface Physics and Chemistry Laboratory
- Mianyang 621907
- China
| | - Xinchun Lai
- Nano Chemistry Group
- Science and Technology on Surface Physics and Chemistry Laboratory
- Mianyang 621907
- China
- College of Materials Science and Engineering
| | - Pengxiang Zhao
- Nano Chemistry Group
- Science and Technology on Surface Physics and Chemistry Laboratory
- Mianyang 621907
- China
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29
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Fang B, Jiang Y, Nüsslein K, Rotello VM, Santore MM. Antimicrobial surfaces containing cationic nanoparticles: how immobilized, clustered, and protruding cationic charge presentation affects killing activity and kinetics. Colloids Surf B Biointerfaces 2014; 125:255-63. [PMID: 25480668 DOI: 10.1016/j.colsurfb.2014.10.043] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 08/27/2014] [Accepted: 10/22/2014] [Indexed: 11/29/2022]
Abstract
This work examines how the antimicrobial (killing) activity of net-negative surfaces depends on the presentation of antimicrobial cationic functionality: distributed versus clustered, and flat clusters versus raised clusters. Specifically, the ability to kill Staphylococcus aureus by sparsely distributed 10 nm cationic nanoparticles, immobilized on a negative surface and backfilled with a PEG (polyethylene glycol) brush, was compared with that for a dense layer of the same immobilized nanoparticles. Additionally, sparsely distributed 10 nm poly-L-lysine (PLL) coils, adsorbed to a surface to produce flat cationic "patches" and backfilled with a PEG brush were compared to a saturated adsorbed layer of PLL. The latter resembled classical uniformly cationic antimicrobial surfaces. The protrusion of the cationic clusters substantially influenced killing but the surface concentration of the clusters had minor impact, as long as bacteria adhered. When surfaces were functionalized at the minimum nanoparticle and patch densities needed for bacterial adhesion, killing activity was substantial within 30 min and nearly complete within 2 h. Essentially identical killing was observed on more densely functionalized surfaces. Surfaces containing protruding (by about 8 nm) nanoparticles accomplished rapid killing (at 30 min) compared with surfaces containing similarly cationic but flat features (PLL patches). Importantly, the overall surface density of cationic functionality within the clusters was lower than reported thresholds for antimicrobial action. Also surprising, the nanoparticles were far more deadly when surface-immobilized compared with free in solution. These findings support a killing mechanism involving interfacial stress.
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Affiliation(s)
- Bing Fang
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA 01003, United States
| | - Ying Jiang
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States
| | - Klaus Nüsslein
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, United States
| | - Vincent M Rotello
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, United States
| | - Maria M Santore
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA 01003, United States.
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30
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Song L, Sjollema J, Sharma PK, Kaper HJ, van der Mei HC, Busscher HJ. Nanoscopic vibrations of bacteria with different cell-wall properties adhering to surfaces under flow and static conditions. ACS NANO 2014; 8:8457-67. [PMID: 25025495 DOI: 10.1021/nn5030253] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Bacteria adhering to surfaces demonstrate random, nanoscopic vibrations around their equilibrium positions. This paper compares vibrational amplitudes of bacteria adhering to glass. Spring constants of the bond are derived from vibrational amplitudes and related to the electrophoretic softness of the cell surfaces and dissipation shifts measured upon bacterial adhesion in a quartz-crystal-microbalance (QCM-D). Experiments were conducted with six bacterial strains with pairwise differences in cell surface characteristics. Vibrational amplitudes were highest in low ionic strength suspensions. Under fluid flow, vibrational amplitudes were lower in the direction of flow than perpendicular to it because stretching of cell surface polymers in the direction of flow causes stiffening of the polyelectrolyte network surrounding a bacterium. Under static conditions (0.57 mM), vibrational amplitudes of fibrillated Streptococcus salivarius HB7 (145 nm) were higher than that of a bald mutant HB-C12 (76 nm). Amplitudes of moderately extracellular polymeric substance (EPS) producing Staphylococcus epidermidis ATCC35983 (47 nm) were more than twice the amplitudes of strongly EPS producing S. epidermidis ATCC35984 (21 nm). No differences were found between Staphylococcus aureus strains differing in membrane cross-linking. High vibrational amplitudes corresponded with low dissipation shifts in QCM-D. In streptococci, the polyelectrolyte network surrounding a bacterium is formed by fibrillar surface appendages and spring constants derived from vibrational amplitudes decreased with increasing fibrillar density. In staphylococci, EPS constitutes the main network component, and larger amounts of EPS yielded higher spring constants. Spring constants increased with increasing ionic strength and strains with smaller electrophoretically derived bacterial cell surface softnesses possessed the highest spring constants.
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Affiliation(s)
- Lei Song
- Department of Biomedical Engineering, University of Groningen and University Medical Center Groningen , Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
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Meng J, Zhang P, Wang S. Recent Progress in Biointerfaces with Controlled Bacterial Adhesion by Using Chemical and Physical Methods. Chem Asian J 2014; 9:2004-16. [DOI: 10.1002/asia.201402200] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Indexed: 11/12/2022]
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Wen Y, Guo X, Kalasin S, Santore MM. Capture of soft particles on electrostatically heterogeneous collectors: brushy particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:2019-2027. [PMID: 24559048 DOI: 10.1021/la404235g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This work investigated how particle softness can influence the initial adhesive capture of submicrometer colloidal particles from flow onto collecting surfaces. The study focused on the case dominated by potential attractions at the particle periphery (rather than, for instance, steric stabilization, requiring entropically costly deformations to access shorter-range van der Waals attractions.) The particles, "spherical polyelectrolyte brushes" with diameters in the range of 150-200 nm depending on the ionic strength, consisted of a polystyrene core and a corona of grafted poly(acrylic acid) chains, producing a relatively thick (20-40 nm) negative brushy layer. The adhesion of these particles was studied on electrostatically heterogeneous collecting surfaces: negatively charged substrates carrying flat polycationic patches made by irreversibly adsorbing the poly-l-lysine (PLL) polyelectrolyte. Variation in the amount of adsorbed PLL changed the net collector charge from completely negatively charged (repulsive) to positively charged (attractive). Adjustments in ionic strength varied the range of the electrostatic interactions. Comparing capture kinetics of soft brushy particles to those of similarly sized and similarly charged silica particles revealed nearly identical particle capture kinetics over the full range of collecting surface compositions at high ionic strengths. Even though the brushy particles contained an average of 5 vol % PAA in the brushy shell, with the rest being water under these conditions, their capture was indistinguishable from that of similarly charged rigid spheres. The brushy particles were, however, considerably less adherent at low ionic strengths where the brush was more extended, suggesting an influence of particle deformability or reduced interfacial charge. These findings, that the short time adhesion of brushy particles can resemble that of rigid particles, suggest that for bacteria and cell capture, modeling the cells as rigid particles can, in some instances, be a good approximation.
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Affiliation(s)
- Yicun Wen
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, People's Republic of China
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