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Aasim M, Khan MH, Bibi NS, Fernandez-Lahore M. Understanding the interaction of proteins to ion exchange chromatographic supports: A surface energetics approach. Biotechnol Prog 2022; 38:e3232. [PMID: 35037430 DOI: 10.1002/btpr.3232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/17/2021] [Accepted: 01/10/2022] [Indexed: 11/10/2022]
Abstract
Ion exchange chromatography is one of the most widely used chromatographic technique for the separation and purification of important biological molecules. Due to its wide applicability in separation processes, a targeted approach is required to suggest the effective binding conditions during ion exchange chromatography. A surface energetics approach was used to study the interaction of proteins to different types of ion exchange chromatographic beads. The basic parameters used in this approach are derived from the contact angle, streaming potential, and zeta potential values. The interaction of few model proteins to different anionic and cationic exchanger, with different backbone chemistry i.e., agarose and methacrylate, was performed. Generally, under binding conditions, it was observed that proteins having negative surface charges showed strong to lose interaction (20 kT for Hannilase to 0.5 kT for IgG) with different anionic exchangers (having different positive surface charges). On the contrary, anionic exchangers showed almost no interaction (0 - 0.1 kT) with the positively charged proteins. An inverse behavior was observed for the interaction of proteins to cationic exchangers. The outcome from these theoretical calculations can predict the binding behavior of different proteins under real ion exchange chromatographic conditions. This will ultimately propose a better bioprocess design for protein separation. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Muhammad Aasim
- Department of Biotechnology, University of Malakand, Lower Dir, Khyber Pakhtunkhwa, Pakistan
| | - Muhammad H Khan
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, P. R. China
| | - Noor Shad Bibi
- Department of Biochemistry, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Marcelo Fernandez-Lahore
- Downstream Bioprocessing Laboratory, School of Engineering and Science, Jacobs University, Campus Ring 1, Bremen, Germany
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Harada LK, Silva EC, Rossi FP, Cieza B, Oliveira TJ, Pereira C, Tomazetto G, Silva BB, Squina FM, Vila MM, Setubal JC, Ha T, da Silva AM, Balcão VM. Characterization and in vitro testing of newly isolated lytic bacteriophages for the biocontrol of Pseudomonas aeruginosa. Future Microbiol 2022; 17:111-141. [PMID: 34989245 DOI: 10.2217/fmb-2021-0027] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Aim: Two lytic phages were isolated using P. aeruginosa DSM19880 as host and fully characterized. Materials & methods: Phages were characterized physicochemically, biologically and genomically. Results & conclusion: Host range analysis revealed that the phages also infect some multidrug-resistant (MDR) P. aeruginosa clinical isolates. Increasing MOI from 1 to 1000 significantly increased phage efficiency and retarded bacteria regrowth, but phage ph0034 (reduction of 7.5 log CFU/ml) was more effective than phage ph0031 (reduction of 5.1 log CFU/ml) after 24 h. Both phages belong to Myoviridae family. Genome sequencing of phages ph0031 and ph0034 showed that they do not carry toxin, virulence, antibiotic resistance and integrase genes. The results obtained are highly relevant in the actual context of bacterial resistance to antibiotics.
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Affiliation(s)
- Liliam K Harada
- PhageLab - Laboratory of Biofilms & Bacteriophages, University of Sorocaba, Sorocaba/SP, Brazil
| | - Erica C Silva
- PhageLab - Laboratory of Biofilms & Bacteriophages, University of Sorocaba, Sorocaba/SP, Brazil
| | - Fernando Pn Rossi
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Basilio Cieza
- Department of Biophysics & Biophysical Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Thais J Oliveira
- PhageLab - Laboratory of Biofilms & Bacteriophages, University of Sorocaba, Sorocaba/SP, Brazil
| | - Carla Pereira
- Department of Biology & CESAM, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
| | - Geizecler Tomazetto
- Department of Engineering, Biological & Chemical Engineering Section (BCE), Aarhus University, Aarhus, Denmark
| | - Bianca B Silva
- PhageLab - Laboratory of Biofilms & Bacteriophages, University of Sorocaba, Sorocaba/SP, Brazil
| | - Fabio M Squina
- PhageLab - Laboratory of Biofilms & Bacteriophages, University of Sorocaba, Sorocaba/SP, Brazil
| | - Marta Mdc Vila
- PhageLab - Laboratory of Biofilms & Bacteriophages, University of Sorocaba, Sorocaba/SP, Brazil
| | - João C Setubal
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Taekjip Ha
- Department of Biophysics & Biophysical Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Aline M da Silva
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Victor M Balcão
- PhageLab - Laboratory of Biofilms & Bacteriophages, University of Sorocaba, Sorocaba/SP, Brazil.,Department of Biology & CESAM, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
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Abstract
Colonization of textiles and subsequent metabolic degradation of sweat and sebum components by axillary skin bacteria cause the characteristic sweat malodor and discoloring of dirty clothes. Once inside the textile, the bacteria can form biofilms that are hard to remove by conventional washing. When the biofilm persists after washing, the textiles retain the sweat odor. To design biofilm removal and prevention strategies, the bacterial behavior needs to be understood in depth. Here, we aim to study the bacterial behavior in each of the four stages of the bacterial life cycle in textiles: adhesion, growth, drying, and washing. To accomplish this, we designed a novel in vitro model to mimic physiological sweating in cotton and polyester textiles, in which many of the parameters that influence bacterial behavior could be controlled. Due to the higher hydrophobicity, polyester adhered more bacteria and absorbed more sebum, the bacteria's primary nutrient source. Bacteria were therefore also more active in polyester textiles. However, polyester did not bind water as well as cotton. The increased water content of cotton allowed some species to retain a higher activity after the textile had dried. However, none of the textiles retained enough water upon drying to prevent the bacteria from adhering irreversibly to the textile fibers. This work demonstrates that bacterial colonization of textiles depends partially on the hydrophobic and hygroscopic properties of the textile material, indicating that it might be possible to direct bacterial behavior in a more favorable direction by modifying these surface properties. IMPORTANCE During sweating, bacteria from the skin enter the worn textile along with the sweat. Once inside the clothes, the bacteria produce sweat malodor and form colonies that are extremely hard to remove by washing. Over time, this leads to a decreasing textile quality and consumer comfort. To design prevention and removal mechanisms, we investigated the behavior of bacteria during the four stages of their life cycle in textiles: adhesion, growth, drying, and washing. The bacterial behavior in textiles during all four stages is found to be affected by the textile's ability to bind water and fat. The study indicates that sweat malodor and bacterial accumulation in textiles over time can be reduced by making the textiles more repellant to water and fat.
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Amin ML, Mawad D, Dokos S, Koshy P, Martens PJ, Sorrell CC. Fucoidan- and carrageenan-based biosynthetic poly(vinyl alcohol) hydrogels for controlled permeation. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2021; 121:111821. [PMID: 33579464 DOI: 10.1016/j.msec.2020.111821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 12/14/2020] [Accepted: 12/19/2020] [Indexed: 01/01/2023]
Abstract
Since the permeation of the inflammatory cytokines into hydrogel scaffolds has been shown to cause dysfunction of encapsulated cells, appropriate design strategies to circumvent this are essential. In the present work, it was hypothesized that highly crosslinked PVA-fucoidan and PVA-carrageenan hydrogels can control permeation of the trefoil-shaped inflammatory cytokine IL-1β while allowing the permeation of the globular protein albumin. PVA, fucoidan, and carrageenans were functionalized with methacrylate groups and the functionalized polymers were co-crosslinked by UV photopolymerization. The resultant hydrogels were characterized physicochemically and the release of fucoidan and carrageenans was quantified by developing a colorimetric assay, which was validated by XPS analysis. The permeability characteristics of the hydrogels were evaluated using bovine serum albumin (BSA), IgG, and IL-1β. The results demonstrated an increase in hydrogel swelling through the incorporation of the polysaccharides with minimal overall mass loss. The release studies showed hydrogel stability, where the formulations exhibited ~43% retention of fucoidan and ~60-80% retention of carrageenans consistently up to 7 days. The permeation data revealed very low permeation of IgG and IL-1β through the hydrogels, with <1% permeation after 24 h, while allowing >6% permeation of BSA. These data indicate that such hydrogels can be used as the basis for cytokine-protective implantable devices for clinical applications.
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Affiliation(s)
- Md Lutful Amin
- School of Materials Science and Engineering, UNSW Sydney, Sydney, NSW 2052, Australia; Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia.
| | - Damia Mawad
- School of Materials Science and Engineering, UNSW Sydney, Sydney, NSW 2052, Australia; Centre for Advanced Macromolecular Design, UNSW Sydney, Sydney, NSW 2052, Australia; Australian Centre for NanoMedicine and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Socrates Dokos
- Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Pramod Koshy
- School of Materials Science and Engineering, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Penny Jo Martens
- Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Charles C Sorrell
- School of Materials Science and Engineering, UNSW Sydney, Sydney, NSW 2052, Australia.
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Zhang X, Wei J, Zhou X, Horio A, Li S, Chen Y, Jiang S, Liang Z, Wu Z, Qiu F. Evaluation of modified basalt fiber as biological carrier media for wastewater treatment with the extended DLVO theory model. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:29789-29798. [PMID: 31407258 DOI: 10.1007/s11356-019-06133-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 07/29/2019] [Indexed: 06/10/2023]
Abstract
In this study, environment-friendly inorganic basalt fiber (BF) was used as bio-carrier for wastewater treatment. To enhance the bio-affinity, raw BF was modified by grafting the diethylamino functional groups to make the surface more hydrophilic and electro-positive. Contact angle and zeta potential of modified basalt fiber (MBF) were characterized. The capacity of MBF bio-carriers was evaluated by microorganism immobilization tests. To explain the mechanism of capacity enhancement by modification, the profiles of total interaction energy barrier between raw BF (or MBF) and bacteria (Escherichia coli, E. coli) were discussed based on the extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The results showed the contact angle of fiber decreased from 89.71° to 63.08° after modification, and zeta potential increased from - 18.53 to +10.58 mV. The microorganism immobilization tests showed that the surface modification accelerated the initial bacterial adhesion on fiber. The total interaction energy barrier between MBF and E. coli disappeared as a result of electrostatic and hydrophilic attractive forces, and enhanced the irreversible adhesion. MBF bio-carrier medium provides a promising alternative to conventional bio-carrier materials for wastewater treatment. Graphical abstract.
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Affiliation(s)
- Xiaoying Zhang
- Institute of Environmental Health and Ecological Security, School of the Environment and Safety Engineering, Jiangsu University, Jiangsu, 212013, China
| | - Jing Wei
- Institute of Environmental Health and Ecological Security, School of the Environment and Safety Engineering, Jiangsu University, Jiangsu, 212013, China.
| | - Xiangtong Zhou
- Institute of Environmental Health and Ecological Security, School of the Environment and Safety Engineering, Jiangsu University, Jiangsu, 212013, China
| | - Akihiro Horio
- Department of Civil Engineering, National Institute of Technology, Gunma College, Gunma, 371-8530, Japan
| | - Shanwei Li
- Institute of Environmental Health and Ecological Security, School of the Environment and Safety Engineering, Jiangsu University, Jiangsu, 212013, China
| | - Yuanyuan Chen
- Jiangsu ATK Environmental Engineering R&D Institute, Jiangsu, 214214, China
| | - Suying Jiang
- Jiangsu ATK Environmental Engineering R&D Institute, Jiangsu, 214214, China
| | - Zhishui Liang
- School of Civil Engineering, Southeast University, Jiangsu, 210096, China
| | - Zhiren Wu
- Institute of Environmental Health and Ecological Security, School of the Environment and Safety Engineering, Jiangsu University, Jiangsu, 212013, China.
| | - Fengxian Qiu
- Institute of Environmental Health and Ecological Security, School of the Environment and Safety Engineering, Jiangsu University, Jiangsu, 212013, China
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Liu CT, Tsai CC, Chu CW, Chi MH, Chung PY, Chen JT. Dewetting of polymer thin films on modified curved surfaces: preparation of polymer nanoparticles with asymmetric shapes by anodic aluminum oxide templates. SOFT MATTER 2018; 14:2772-2776. [PMID: 29620121 DOI: 10.1039/c8sm00318a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We study the dewetting behaviors of poly(methyl methacrylate) (PMMA) thin films coated in the cylindrical nanopores of anodic aluminum oxide (AAO) templates by thermal annealing. Self-assembled monolayers (SAMs) of n-octadecyltrichlorosilane (ODTS) are introduced to modify the pore surfaces of the AAO templates to induce the dewetting process. By using scanning electron microscopy (SEM), the dewetting-induced morphology transformation from the PMMA thin films to PMMA nanoparticles with asymmetric shapes can be observed. The sizes of the PMMA nanoparticles can be controlled by the original PMMA solution concentrations. The dewetting phenomena on the modified nanopores are explained by taking into account the excess intermolecular interaction free energy (ΔG). This work opens a new possibility for creating polymer nanoparticles with asymmetric shapes in confined geometries.
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Affiliation(s)
- Chih-Ting Liu
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 30010, Taiwan
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Gonzalez Garcia LE, MacGregor-Ramiasa M, Visalakshan RM, Vasilev K. Protein Interactions with Nanoengineered Polyoxazoline Surfaces Generated via Plasma Deposition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:7322-7331. [PMID: 28658956 DOI: 10.1021/acs.langmuir.7b01279] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Protein adsorption to biomaterials is critical in determining their suitability for specific applications, such as implants or biosensors. Here, we show that surface nanoroughness can be tailored to control the covalent binding of proteins to plasma-deposited polyoxazoline (PPOx). Nanoengineered surfaces were created by immobilizing gold nanoparticles varying in size and surface density on PPOx films. To keep the surface chemistry consistent while preserving the nanotopography, all substrates were overcoated with a nanothin PPOx film. Bovine serum albumin was chosen to study protein interactions with the nanoengineered surfaces. The results demonstrate that the amount of protein bound to the surface is not directly correlated with the increase in surface area. Instead, it is determined by nanotopography-induced geometric effects and surface wettability. A densely packed array of 16 and 38 nm nanoparticles hinders protein adsorption compared to smooth PPOx substrates, while it increases for 68 nm nanoparticles. These adaptable surfaces could be used for designing biomaterials where proteins adsorption is or is not desirable.
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Affiliation(s)
- Laura E Gonzalez Garcia
- School of Engineering, Future Industries Institute, University of South Australia, Mawson Lakes Campus , Mawson Lakes, South Australia 5095, Australia
| | - Melanie MacGregor-Ramiasa
- School of Engineering, Future Industries Institute, University of South Australia, Mawson Lakes Campus , Mawson Lakes, South Australia 5095, Australia
| | - Rahul Madathiparambil Visalakshan
- School of Engineering, Future Industries Institute, University of South Australia, Mawson Lakes Campus , Mawson Lakes, South Australia 5095, Australia
| | - Krasimir Vasilev
- School of Engineering, Future Industries Institute, University of South Australia, Mawson Lakes Campus , Mawson Lakes, South Australia 5095, Australia
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Retention of poly(N-isopropylacrylamide) on 3-aminopropyltriethoxysilane. Biointerphases 2017; 12:02C405. [PMID: 28449584 DOI: 10.1116/1.4982248] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Silane coupling agents are commonly employed to link an organic polymer to an inorganic substrate. One of the widely utilized coupling agents is 3-aminopropyltriethoxy silane (APTES). In this study, the authors investigated the ability of APTES to retain thermo-responsive poly(N-isopropylacrylamide) (pNIPAAm) on hydroxylated surfaces such as glass. For comparison purposes, the authors also evaluated the retention behaviors of (1) polystyrene, which likely has weaker van der Waals interactions and acid-base interactions (contributed by hydrogen-bonding) with APTES, on APTES as well as (2) pNIPAAm on two other silane coupling agents, which have similar structures to APTES, but exhibit less interaction with pNIPAAm. Under our processing conditions, the stronger interactions, particularly hydrogen bonding, between pNIPAAm and APTES were found to contribute substantially to the retention of pNIPAAm on the APTES modified surface, especially on the cured APTES layer when the interpenetration was minimal or nonexistent. On the noncured APTES layer, the formation of an APTES-pNIPAAm interpenetrating network resulted in the retention of thicker pNIPAAm films. As demonstrated by water contact angles [i.e., 7°-15° higher at 40 °C, the temperature above the lower critical solution temperature (LCST) of 32 °C for pNIPAAm, as compared to those at 25 °C] and cell attachment and detachment behaviors (i.e., attached/spread at 37 °C, above LCST; detached at 20 °C, below LCST), the retained pNIPAAm layer (6-15 nm), on both noncured and cured APTES, exhibited thermo-responsive behavior. The results in this study illustrate the simplicity of using the coupling/adhesion promoting ability of APTES to retain pNIPAAm films on hydroxylated substrates, which exhibit faster cell sheet detachment (≤30 min) as compared to pNIPAAm brushes (in hours) prepared using tedious and costly grafting approaches. The use of adhesion promoters to retain pNIPAAm provides an affordable alternative to current thermo-responsive supports for cell sheet engineering and stem cell therapy applications.
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Laganapan A, Bochicchio D, Bienia M, Videcoq A, Ferrando R. Aggregation of binary colloidal suspensions on attractive walls. Phys Chem Chem Phys 2016; 18:3073-9. [PMID: 26739745 DOI: 10.1039/c5cp07050c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The adsorption of colloidal particles from a suspension on a solid surface is of fundamental importance to many physical and biological systems. In this work, Brownian Dynamics simulations are performed to study the aggregation in a suspension of oppositely charged colloidal particles in the presence of an attractive wall. For sufficiently strong attractions, the wall alters the microstructure of the aggregates so that B2 (CsCl-type) structures are more likely obtained instead of B1 (NaCl-type) structures. The probability of forming either B1 or B2 crystallites depends also on the inverse interaction range κa. Suspensions with small κa are more likely to form B2 crystals than suspensions with larger κa, even if the energetic stability of the B2 phase decreases with decreasing κa. The mechanisms underlying this aggregation and crystallization behaviour are analyzed in detail.
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Affiliation(s)
- Aleena Laganapan
- SPCTS, UMR 7315, ENSCI, CNRS, Centre Européen de la Céramique, 12 rue Atlantis, 87068 Limoges cedex, France and Dipartimento di Fisica, via Dodecaneso 33, 16146, Genova, Italy
| | | | - Marguerite Bienia
- SPCTS, UMR 7315, ENSCI, CNRS, Centre Européen de la Céramique, 12 rue Atlantis, 87068 Limoges cedex, France
| | - Arnaud Videcoq
- SPCTS, UMR 7315, ENSCI, CNRS, Centre Européen de la Céramique, 12 rue Atlantis, 87068 Limoges cedex, France
| | - Riccardo Ferrando
- Dipartimento di Chimica e Chimica Industriale and CNR-IMEM, via Dodecaneso 31, 16146, Genova, Italy.
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Mustin B, Stoeber B. Single Layer Deposition of Polystyrene Particles onto Planar Polydimethylsiloxane Substrates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:88-101. [PMID: 26646665 DOI: 10.1021/acs.langmuir.5b02914] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This work investigates the deposition of polystyrene particles onto cross-linked polydimethylsiloxane (PDMS) substrates by using an impinging jet flow cell for different concentrations of sodium chloride in solution. Particle tracking reveals that particles near the substrate can be immobilized to different degrees. An attempt is made to classify the mobility of the particles close to the surface by distinguishing between weakly immobilized and strongly immobilized particles where only the latter ones are considered as deposited. Subsequently, the measured initial deposition rates for different concentrations of sodium chloride in solution are compared to the commonly applied theory based on the convective diffusion equation in which different surface interaction potentials were considered. With currently available data on the surface properties of PDMS, the extended Derjaguin-Landau-Verwey-Overbeek (extended DLVO) theory gave a better description of the observed deposition rates as compared to the DLVO theory; however, in either case, the presence of significant surface charge heterogeneity had to be assumed in order to capture the observed trend of the deposition rates with respect to the electrolyte concentration. Careful analysis of the more weakly immobilized particles through particle displacement step analysis reveals that there is a buildup of a particle accumulation layer near the substrate in which particle motion parallel to the substrate is hindered by nonhydrodynamic effects. Possible reasons for the reduced particle motion in the accumulation layer are discussed. As a result, the presence of lateral surface interaction forces resulting from charge heterogeneity and surface roughness of the PDMS substrate is found to be the most plausible explanation for the hindered particle motion in the accumulation layer. This suggests that particles associated with the secondary minimum of the surface interaction potential may not always be freely mobile in any direction parallel to the substrate.
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Affiliation(s)
- B Mustin
- The University of British Columbia , 2054-6250 Applied Science Lane, Vancouver, BC V6T 1Z4, Canada
| | - B Stoeber
- The University of British Columbia , 2054-6250 Applied Science Lane, Vancouver, BC V6T 1Z4, Canada
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