1
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Dias Neves MA, Mendes Pinto I. AptaShield: A Universal Signal-Transduction System for Fast and High-Throughput Optical Molecular Biosensing. ACS Sens 2024; 9:1756-1762. [PMID: 38620013 PMCID: PMC11059090 DOI: 10.1021/acssensors.3c02762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/11/2024] [Accepted: 03/22/2024] [Indexed: 04/17/2024]
Abstract
Biosensing technologies are often described to provide facile, sensitive, and minimally to noninvasive detection of molecular analytes across diverse scientific, environmental, and clinical diagnostic disciplines. However, commercialization has been very limited mostly due to the difficulty of biosensor reconfiguration for different analyte(s) and limited high-throughput capabilities. The immobilization of different biomolecular probes (e.g., antibodies, peptides, and aptamers) requires the sensor surface chemistry to be tailored to provide optimal probe coupling, orientation, and passivation and prevent nonspecific interactions. To overcome these challenges, here we report the development of a solution-phase biosensor consisting of an engineered aptamer, the AptaShield, capable of universally binding to any antigen recognition site (Fab') of fluorescently labeled immunoglobulins (IgG) produced in rabbits. The resulting AptaShield biosensor relies on a low affinity dynamic equilibrium between the fluorescently tagged aptamer and IgG to generate a specific Förster resonance energy transfer (FRET) signal. As the analyte binds to the IgG, the AptaShield DNA aptamer-IgG complex dissociates, leading to an analyte concentration-dependent decrease of the FRET signal. The biosensor demonstrates high selectivity, specificity, and reproducibility for analyte quantification in different biological fluids (e.g., urine and blood serum) in a one-step and low sample volume (0.5-6.25 μL) format. The AptaShield provides a universal signal transduction mechanism as it can be coupled to different rabbit antibodies without the need for aptamer modification, therefore representing a robust high-throughput solution-phase technology suitable for point-of-care applications, overcoming the current limitations of gold standard enzyme-linked immunosorbent assays (ELISA) for molecular profiling.
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Affiliation(s)
- Miguel António Dias Neves
- Institute
for Research and Innovation in Health (i3S), University of Porto, 4200-135 Porto, Portugal
- Molecular
and Analytical Medicine Laboratory, Department of Biomedicine, Faculty
of Medicine, University of Porto, 4200-319 Porto, Portugal
| | - Inês Mendes Pinto
- Institute
for Research and Innovation in Health (i3S), University of Porto, 4200-135 Porto, Portugal
- Molecular
and Analytical Medicine Laboratory, Department of Biomedicine, Faculty
of Medicine, University of Porto, 4200-319 Porto, Portugal
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2
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Ahmadi S, Lotay N, Thompson M. Affinity-based electrochemical biosensor with antifouling properties for detection of lysophosphatidic acid, a promising early-stage ovarian cancer biomarker. Bioelectrochemistry 2023; 153:108466. [PMID: 37244204 DOI: 10.1016/j.bioelechem.2023.108466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/09/2023] [Accepted: 05/12/2023] [Indexed: 05/29/2023]
Abstract
Electrochemical techniques are considered to be highly sensitive, capable of fast response and can be easily miniaturized, properties which can aid with regard to the fabrication of compact point-of-care medical devices; however, the main challenge in developing such a tool is overcoming a ubiquitous, problematic phenomenon known as non-specific adsorption (NSA). NSA is due to the fouling of non-target molecules in the blood on the recognition surface of the device. To overcome NSA, we have developed an affinity-based electrochemical biosensor using medical-grade stainless steel electrodes and following a unique and novel strategy using silane-based interfacial chemistry to detect lysophosphatidic acid (LPA), a highly promising biomarker, which was found to be elevated in 90 % of stage I OC patients and gradually increases as the disease progresses to later stages. The biorecognition surface was developed using the affinity-based gelsolin-actin system, which was previously investigated by our group to detect LPA using fluorescence spectroscopy. We demonstrate the capability of this label-free biosensor to detect LPA in goat serum with a detection limit of 0.7 µM as a proof-of-concept for the early diagnosis of ovarian cancer.
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Affiliation(s)
- Soha Ahmadi
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Navina Lotay
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada.
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3
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Spagnolo S, Davoudian K, De La Franier B, Hianik T, Thompson M. Staphylococcus aureus Detection in Milk Using a Thickness Shear Mode Acoustic Aptasensor with an Antifouling Probe Linker. BIOSENSORS 2023; 13:614. [PMID: 37366979 DOI: 10.3390/bios13060614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 05/25/2023] [Accepted: 06/01/2023] [Indexed: 06/28/2023]
Abstract
Contamination of food by pathogens can pose a serious risk to health. Therefore, monitoring for the presence of pathogens is critical to identify and regulate microbiological contamination of food. In this work, an aptasensor based on a thickness shear mode acoustic method (TSM) with dissipation monitoring was developed to detect and quantify Staphylococcus aureus directly in whole UHT cow's milk. The frequency variation and dissipation data demonstrated the correct immobilization of the components. The analysis of viscoelastic properties suggests that DNA aptamers bind to the surface in a non-dense manner, which favors the binding with bacteria. The aptasensor demonstrated high sensitivity and was able to detect S. aureus in milk with a 33 CFU/mL limit of detection. Analysis was successful in milk due to the sensor's antifouling properties, which is based on 3-dithiothreitol propanoic acid (DTTCOOH) antifouling thiol linker. Compared to bare and modified (dithiothreitol (DTT), 11-mercaptoundecanoic acid (MUA), and 1-undecanethiol (UDT)) quartz crystals, the sensitivity of the sensor's antifouling in milk improved by about 82-96%. The excellent sensitivity and ability to detect and quantify S. aureus in whole UHT cow's milk demonstrates that the system is applicable for rapid and efficient analysis of milk safety.
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Affiliation(s)
- Sandro Spagnolo
- Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská Dolina F1, 84248 Bratislava, Slovakia
| | - Katharina Davoudian
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S3H6, Canada
| | - Brian De La Franier
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S3H6, Canada
| | - Tibor Hianik
- Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská Dolina F1, 84248 Bratislava, Slovakia
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S3H6, Canada
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4
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De La Franier B, Asker D, Hatton B, Thompson M. Long-Term Reduction of Bacterial Adhesion on Polyurethane by an Ultra-Thin Surface Modifier. Biomedicines 2022; 10:979. [PMID: 35625716 PMCID: PMC9138992 DOI: 10.3390/biomedicines10050979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/12/2022] [Accepted: 04/21/2022] [Indexed: 11/16/2022] Open
Abstract
Indwelling urinary catheters are employed widely to relieve urinary retention in patients. A common side effect of the use of these catheters is the formation of urinary tract infections (UTIs), which can lead not only to severe medical complications, but even to death. A number of approaches have been used to attempt reduction in the rate of UTI development in catheterized patients, which include the application of antibiotics and modification of the device surface by coatings. Many of these coatings have not seen use on catheters in medical settings due to either the high cost of their implementation, their long-term stability, or their safety. In previous work, it has been established that the simple, stable, and easily applicable sterilization surface coating 2-(3-trichlorosilylpropyloxy)-ethyl hydroxide (MEG-OH) can be applied to polyurethane plastic, where it greatly reduces microbial fouling from a variety of species for a 1-day time period. In the present work, we establish that this coating is able to remain stable and provide a similarly large reduction in fouling against Escherichia coli and Staphylococcus aureus for time periods in an excess of 30 days. This non-specific coating functioned against both Gram-positive and Gram-negative bacteria, providing a log 1.1 to log 1.9 reduction, depending on the species and day. This stability and continued efficacy greatly suggest that MEG-OH may be capable of providing a solution to the UTI issue which occurs with urinary catheters.
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Affiliation(s)
- Brian De La Franier
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada;
| | - Dalal Asker
- Department of Materials Science, University of Toronto, 184 College Street, Toronto, ON M5S 3E4, Canada; or (D.A.); (B.H.)
- Food Science and Technology Department, Faculty of Agriculture, Alexandria University, Alexandria 21545, Egypt
| | - Benjamin Hatton
- Department of Materials Science, University of Toronto, 184 College Street, Toronto, ON M5S 3E4, Canada; or (D.A.); (B.H.)
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada;
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5
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Interaction of Lipopolysaccharide-Spiked Blood with Anti-Fouling Polymyxin B-Modified Glass. MATERIALS 2022; 15:ma15041551. [PMID: 35208091 PMCID: PMC8876862 DOI: 10.3390/ma15041551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/07/2022] [Accepted: 02/14/2022] [Indexed: 11/20/2022]
Abstract
Bacterial endotoxin, also known as lipopolysaccharide (LPS), plays a major role in the initiation of sepsis, a severe inflammatory condition. Removal of the toxin from blood is one accepted method of patient treatment. Polymyxin B (PMB)-modified columns have been employed successfully for this purpose via extra-corporeal blood-flow systems that incorporate a cartridge for toxin removal. Herein we demonstrate that PMB-modified glass beads are able to reduce the presence of LPS competitively with the equivalent fiber column used in a commercial cartridge. Analysis by gas chromatography-mass spectrometry and ELISA of released fatty acids from the toxin indicates that PMB does not physically capture or significantly remove LPS from the blood samples. In reality, interaction between the surface-bound PMB and the toxin may lead to disaggregation or monomerization of LPS aggregates. As aggregates are the bioactive form of LPS, it is possible that the monomerization of these entities may be the mechanism by which their toxicity is reduced. Moreover, this work indicates that LPS monomers are stabilized subsequent to disaggregation induced by PMB.
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6
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De La Franier B, Thompson M. Surface Adsorption of the Cancer Biomarker Lysophosphatidic Acid in Serum Studied by Acoustic Wave Biosensor. MATERIALS (BASEL, SWITZERLAND) 2021; 14:4158. [PMID: 34361352 PMCID: PMC8347737 DOI: 10.3390/ma14154158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 11/16/2022]
Abstract
The thickness shear mode acoustic wave device is of interest for the sensing of biomarkers for diseases in various biological fluids, but suffers from the issue of non-specific adsorption of compounds other than those of interest to the electrode surface, thus affecting the device's output. The aim of this present study was to determine the level of non-specific adsorption on gold electrodes from serum samples with added ovarian cancer biomarker lysophosphatidic acid in the presence of a surface anti-fouling layer. The latter was an oligoethylene molecule with thiol group for attachment to the electrode surface. It was found that the anti-fouling layer had a minimal effect on the level of both adsorption of components from serum and the marker. This result stands in sharp contrast to the analogous monolayer employed for anti-fouling reduction on silica.
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Affiliation(s)
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada;
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7
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Yang T, De La Franier B, Thompson M. Anti-Thrombogenicity Study of a Covalently-Attached Monolayer on Stent-Grade Stainless Steel. MATERIALS 2021; 14:ma14092342. [PMID: 33946387 PMCID: PMC8125229 DOI: 10.3390/ma14092342] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/21/2021] [Accepted: 04/26/2021] [Indexed: 12/16/2022]
Abstract
Implantable devices fabricated from austenitic type 316L stainless steel have been employed significantly in medicine, principally because the material displays excellent mechanical characteristics and corrosion resistance. It is well known, however, that interaction of exposure of such a material to blood can initiate platelet adhesion and blood coagulation, leading to a harmful medical condition. In order to prevent undesirable surface platelet adhesion on biomaterials employed in procedures such as renal dialysis, we developed an ultrathin anti-thrombogenic covalently attached monolayer based on monoethylene glycol silane chemistry. This functions by forming an interstitial hydration layer which displays restricted mobility in the prevention of surface fouling. In the present work, the promising anti-thrombogenic properties of this film are examined with respect to platelet aggregation on 316L austenitic stainless steel exposed to whole human blood. Prior to exposure with blood, all major surface modification steps were examined by X-ray photoelectron spectroscopic analysis and surface free-angle measurement by contact angle goniometry. End-stage anti-thrombogenicity detection after 20 min of blood exposure at 100 s-1, 300 s-1, 600 s-1, 750 s-1, and 900 s-1 shear rates revealed that a significant reduction (>90%) of platelet adhesion and aggregation was achieved for surface-modified steel, compared with untreated material. This result is confirmed by experiments conducted in real time for 60-minute exposure to blood at 100 s-1, 600 s-1, and 900 s-1 shear rates.
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8
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Assembling Surface Linker Chemistry with Minimization of Non-Specific Adsorption on Biosensor Materials. MATERIALS 2021; 14:ma14020472. [PMID: 33478142 PMCID: PMC7835736 DOI: 10.3390/ma14020472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/08/2021] [Accepted: 01/13/2021] [Indexed: 01/04/2023]
Abstract
The operation of biosensors requires surfaces that are both highly specific towards the target analyte and that are minimally subject to fouling by species present in a biological fluid. In this work, we further examined the thiosulfonate-based linker in order to construct robust and durable self-assembling monolayers (SAMs) onto hydroxylated surfaces such as silica. These SAMs are capable of the chemoselective immobilization of thiol-containing probes (for analytes) under aqueous conditions in a single, straightforward, reliable, and coupling-free manner. The efficacy of the method was assessed through implementation as a biosensing interface for an ultra-high frequency acoustic wave device dedicated to the detection of avidin via attached biotin. Fouling was assessed via introduction of interfering bovine serum albumin (BSA), IgG antibody, or goat serum. Improvements were investigated systematically through the incorporation of an oligoethylene glycol backbone employed together with a self-assembling diluent without a functional distal group. This work demonstrates that the incorporation of a diluent of relatively short length is crucial for the reduction of fouling. Included in this work is a comparison of the surface attachment of the linker to Si3N4 and AlN, both materials used in sensor technology.
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9
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De La Franier B, Asker D, van den Berg D, Hatton B, Thompson M. Reduction of microbial adhesion on polyurethane by a sub-nanometer covalently-attached surface modifier. Colloids Surf B Biointerfaces 2021; 200:111579. [PMID: 33517152 DOI: 10.1016/j.colsurfb.2021.111579] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 12/23/2020] [Accepted: 01/11/2021] [Indexed: 01/03/2023]
Abstract
Indwelling urinary catheters are a common medical device used to relieve urinary retention. Many patients who undergo urinary catheterization develop urinary tract infections (UTIs), which can lead to severe medical complications and high cost of subsequent treatment. Recent years have seen a number of attempts at reducing the rate of UTIs in catheterized patients via catheter surface modifications. In this work, a low cost, robust anti-thrombogenic, and sterilizable anti-fouling layer based on a covalently-bound monoethylene glycol hydroxide (MEG-OH) was attached to polyurethane, a polymeric material commonly used to fabricate catheters. Modified polyurethane tubing was compared to bare tubing after exposure to a wide spectrum of pathogens including Gram-negative bacteria (Pesudomonas aeruginosa, Escherichia coli), Gram-positive bacteria (Staphylococcus aureus) and a fungus (Candida albicans). It has been demonstrated that the MEG-OH monolayer was able to significantly reduce the amount of adhesion of pathogens present on the material surface, with between 85 and 96 % reduction after 24 h of exposure. Additionally, similar reductions in surface fouling were observed following autoclave sterilization, long term storage of samples in air, and longer exposure up to 3 days.
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Affiliation(s)
- Brian De La Franier
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada
| | - Dalal Asker
- Department of Materials Science, University of Toronto, 140-184 College St, Toronto, Ontario, M5S 3E4, Canada; Food Science & Technology Department, Faculty of Agriculture, Alexandria University, 21545 - El-Shatby, Alexandria, Egypt
| | - Desmond van den Berg
- Department of Materials Science, University of Toronto, 140-184 College St, Toronto, Ontario, M5S 3E4, Canada
| | - Benjamin Hatton
- Department of Materials Science, University of Toronto, 140-184 College St, Toronto, Ontario, M5S 3E4, Canada
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
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10
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Lin C, Darling GR, Forster M, McBride F, Massey A, Hodgson A. Hydration of a 2D Supramolecular Assembly: Bitartrate on Cu(110). J Am Chem Soc 2020; 142:13814-13822. [PMID: 32692550 PMCID: PMC7458425 DOI: 10.1021/jacs.0c04747] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
![]()
Hydration
layers play a key role in many technical and biological
systems, but our understanding of these structures remains very limited.
Here, we investigate the molecular processes driving hydration of
a chiral metal–organic surface, bitartrate on Cu(110), which
consists of hydrogen-bonded bitartrate rows separated by exposed Cu.
Initially water decorates the metal channels, hydrogen bonding to
the exposed O ligands that bind bitartrate to Cu, but does not wet
the bitartrate rows. At higher temperature, water inserts into the
structure, breaks the existing intermolecular hydrogen bonds, and
changes the adsorption site and footprint. Calculations show this
process is driven by the creation of stable adsorption sites between
the carboxylate ligands, to allow hydration of O–Cu ligands
within the interior of the structure. This work suggests that hydration
of polar metal–adsorbate ligands will be a dominant factor
in many systems during surface hydration or self-assembly from solution.
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Affiliation(s)
- Chenfang Lin
- Surface Science Research Centre and Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - George R Darling
- Surface Science Research Centre and Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Matthew Forster
- Surface Science Research Centre and Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Fiona McBride
- Surface Science Research Centre and Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Alan Massey
- Surface Science Research Centre and Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Andrew Hodgson
- Surface Science Research Centre and Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
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11
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Stoev K, Sakurai K. Recent Progresses in Nanometer Scale Analysis of Buried Layers and Interfaces in Thin Films by X-rays and Neutrons. ANAL SCI 2020; 36:901-922. [PMID: 32147630 DOI: 10.2116/analsci.19r010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In the early 1960s, scientists achieved the breakthroughs in the fields of solid surfaces and artificial layered structures. The advancement of surface science has been supported by the advent of ultra-high vacuum technologies, newly discovered and established scanning probe microscopy with atomic resolution, as well as some other advanced surface-sensitive spectroscopy and microscopy. On the other hand, it has been well recognized that a number of functions are related to the structures of the interfaces, which are the thin planes connecting different materials, most likely by layering thin films. Despite the scientific significance, so far, research on such buried layers and interfaces has been limited, because the probing depth of almost all existing sophisticated analytical methods is limited to the top surface. The present article describes the recent progress in the nanometer scale analysis of buried layers and interfaces, particularly by using X-rays and neutrons. The methods are essentially promising to non-destructively probe such buried structures in thin films. The latest scientific research has been reviewed, and includes applications to bio-chemical, organic, electronic, magnetic, spintronic, self-organizing and complicated systems as well as buried liquid-liquid and solid-liquid interfaces. Some emerging analytical techniques and instruments, which provide new attractive features such as imaging and real time analysis, are also discussed.
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12
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Penna M, Yarovsky I. Nanoscale in silico classification of ligand functionalised surfaces for protein adsorption resistance. NANOSCALE 2020; 12:7240-7255. [PMID: 32196038 DOI: 10.1039/c9nr10009a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Non-specific protein adsorption represents a significant challenge for the design of efficient and safe nanoparticles for biomedical applications since it may prevent functional ligands to target the desired specific receptors which can limit the efficacy of novel drug delivery systems and biosensors. The biofilm formation initiated by protein adsorption on surfaces limits the lifetime and safety of medical implants and tissue regenerative scaffolds. The development of biofouling resistant surfaces is therefore a major goal for the widespread uptake of nanomedicine. Here, we provide a relatively simple computational screening method based on the rational physically grounded criteria that may suffice in selection of surface grafted ligands for protein rejection, and test whether these criteria can be extrapolated from a specific protein to generic protein-resistant surfaces. Using all-atom molecular dynamics simulations we characterise four types of ligand functionalised surfaces at aqueous interfaces in terms of the surface hydrophobicity and ligand dynamics. We demonstrate how our hypothesised interfacial design based on the select physical characteristics of the ligated surfaces can enable the rejection of a protein from the surface. The ligand screening procedure and the detailed atomistic characterisation of the protein rejection process presented suggest that minimizing the adsorption of surface active proteins requires specific surface topographies and ligand chemistries that are able to maximise the entropic penalty associated with the restriction of the ligand dynamics and trapping interfacial water by adsorbed proteins.
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Affiliation(s)
- Matthew Penna
- School of Engineering, RMIT University, Melbourne, VIC 3000, Australia.
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13
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Spagnolo S, De La Franier B, Hianik T, Thompson M. Surface Probe Linker with Tandem Anti-Fouling Properties for Application in Biosensor Technology. BIOSENSORS-BASEL 2020; 10:bios10030020. [PMID: 32138172 PMCID: PMC7146171 DOI: 10.3390/bios10030020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/18/2020] [Accepted: 02/26/2020] [Indexed: 12/22/2022]
Abstract
This paper describes the anti-fouling capability of the novel monolayer-forming surface linker 3-(3-(trichlorosilylpropyloxy) propanoyl chloride (MEG-Cl). This compound was successfully attached to quartz crystal surfaces which are employed in an electromagnetic piezoelectric acoustic sensor (EMPAS) configuration. The MEG-Cl coated surface was both employed with Ni-NTA for the binding of recombinant proteins and for the tandem property of the avoidance of fouling from serum and milk. The MEG-Cl coated surfaces were found to provide a large degree of anti-fouling on the EMPAS device, and were comparable to previously studied MEG-OH surfaces. Importantly, the monolayer continued to provide anti-fouling capability to the biosensor following extension with Ni-NTA in place. Accordingly, this surface linker provides an attractive system for use in biosensor technology in terms of both its anti-fouling and linking properties.
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Affiliation(s)
- Sandro Spagnolo
- Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina F1, 842 48 Bratislava, Slovakia; (S.S.); (T.H.)
| | - Brian De La Franier
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S, Canada;
| | - Tibor Hianik
- Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina F1, 842 48 Bratislava, Slovakia; (S.S.); (T.H.)
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S, Canada;
- Correspondence: ; Tel.: +1-416-978-3575
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14
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Gao N, Fan W, Xu ZK. Ceramic membrane with protein-resistant surface via dopamine/diglycolamine co-deposition. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2019.116135] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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De La Franier B, Thompson M. Detection of the Ovarian Cancer Biomarker Lysophosphatidic Acid in Serum. BIOSENSORS-BASEL 2020; 10:bios10020013. [PMID: 32075013 PMCID: PMC7168251 DOI: 10.3390/bios10020013] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/06/2020] [Accepted: 02/11/2020] [Indexed: 02/07/2023]
Abstract
Lysophosphatidic acid (LPA) is present during the medical condition of ovarian cancer at all stages of the disease, and, therefore possesses considerable potential as a biomarker for screening its presence in female patients. Unfortunately, there is currently no clinically employable assay for this biomarker. In the present work, we introduce a test based on the duel protein system of actin and gelsolin that could allow the quantitative measurement of LPA in serum samples in a biosensing format. In order to evaluate this possibility, actin protein was dye-modified and complexed with gelsolin protein, followed by surface deposition onto silica nanoparticles. This solid-phase system was exposed to serum samples containing various concentrations of LPA and analyzed by fluorescence microscopy. Measurements conducted for the LPA-containing serum samples were higher after exposure to the developed test than samples without LPA. Early results suggest a limit of detection of 5 μM LPA in serum. The eventual goal is to employ the chemistry described here in a biosensor configuration for the large population-scale, rapid screening of women for the potential occurrence of ovarian cancer.
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16
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Fies WA, First JT, Dugger JW, Doucet M, Browning JF, Webb LJ. Quantifying the Extent of Hydration of a Surface-Bound Peptide Using Neutron Reflectometry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:637-649. [PMID: 31846580 DOI: 10.1021/acs.langmuir.9b02559] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Establishing how water, or the absence of water, affects the structure, dynamics, and function of proteins in contact with inorganic surfaces is critical to developing successful protein immobilization strategies. In the present article, the quantity of water hydrating a monolayer of helical peptides covalently attached to self-assembled monolayers (SAMs) of alkyl thiols on Au was measured using neutron reflectometry (NR). The peptide sequence was composed of repeating LLKK units in which the leucines were aligned to face the SAM. When immersed in water, NR measured 2.7 ± 0.9 water molecules per thiol in the SAM layer and between 75 ± 13 and 111 ± 13 waters around each peptide. The quantity of water in the SAM was nearly twice that measured prior to peptide functionalization, suggesting that the peptide disrupted the structure of the SAM. To identify the location of water molecules around the peptide, we compared our NR data to previously published molecular dynamics simulations of the same peptide on a hydrophobic SAM in water, revealing that 49 ± 5 of 95 ± 8 total nearby water molecules were directly hydrogen-bound to the peptide. Finally, we show that immersing the peptide in water compressed its structure into the SAM surface. Together, these results demonstrate that there is sufficient water to fully hydrate a surface-bound peptide even at hydrophobic interfaces. Given the critical role that water plays in biomolecular structure and function, these results are expected to be informative for a broad array of applications involving proteins at the bio/abio interface.
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Affiliation(s)
- Whitney A Fies
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 2506 Speedway STOP A5300 , Austin , Texas 78712 , United States
| | - Jeremy T First
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 2506 Speedway STOP A5300 , Austin , Texas 78712 , United States
| | - Jason W Dugger
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37830 , United States
| | - Mathieu Doucet
- Neutron Scattering Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - James F Browning
- Neutron Scattering Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Lauren J Webb
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 2506 Speedway STOP A5300 , Austin , Texas 78712 , United States
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17
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Sayin M, Nefedov A, Zharnikov M. Interaction of water with oligo(ethylene glycol) terminated monolayers: wetting versus hydration. Phys Chem Chem Phys 2020; 22:8088-8095. [DOI: 10.1039/d0cp00906g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Exposure of biorepulsive, oligo(ethylene glycol) (OEG) substituted self-assembled monolayers to water results in its adsorption both onto the surface and, with a higher binding energy, into the OEG matrix.
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Affiliation(s)
- Mustafa Sayin
- Applied Physical Chemistry
- Heidelberg University
- 69120 Heidelberg
- Germany
| | - Alexei Nefedov
- Institute of Functional Interfaces
- Karlsruhe Institute of Technology (KIT)
- 76344 Eggenstein-Leopoldshafen
- Germany
| | - Michael Zharnikov
- Applied Physical Chemistry
- Heidelberg University
- 69120 Heidelberg
- Germany
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18
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Su H, Li S, Kerman K. Novel thiolated-PEG linker molecule for biosensor development on gold surfaces. Biosens Bioelectron 2019; 141:111477. [DOI: 10.1016/j.bios.2019.111477] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/05/2019] [Accepted: 06/24/2019] [Indexed: 01/01/2023]
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19
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Park E, Lee J, Huh KM, Lee SH, Lee H. Toxicity-Attenuated Glycol Chitosan Adhesive Inspired by Mussel Adhesion Mechanisms. Adv Healthc Mater 2019; 8:e1900275. [PMID: 31091015 DOI: 10.1002/adhm.201900275] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 04/25/2019] [Indexed: 01/04/2023]
Abstract
Chitosan-catechol, inspired from mussel-adhesive-proteins, is characterized by the formation of an adhesive membrane complex through instant bonding with serum proteins not found in chitosan. Using this intrinsic property, chitosan-catechol is widely applied for hemostatic needles, general hemostatic materials, nanoparticle composites, and 3D printing. Despite its versatility, the practical use of chitosan-catechol in the clinic is limited due to its undesired immune responses. Herein, a catechol-conjugated glycol chitosan is proposed as an alternative hemostatic hydrogel with negligible immune responses enabling the replacement of chitosan-catechol. Comparative cellular toxicity and in vivo skin irritation between chitosan-catechol and glycol chitosan-catechol are evaluated. Their immune responses are also assessed using histological analysis after subcutaneous implantation into mice. The results show that glycol chitosan-catechol significantly attenuates the immune response compared with chitosan-catechol; this finding is likely due to the antibiofouling effect of ethylene glycol groups and the reduced adhesion of immune cells. Finally, the tissue adhesion and hemostatic ability of glycol chitosan-catechol hydrogels reveal that these ethylene glycol groups do not dramatically modify the adhesiveness and hemostatic ability compared with nonglycol chitosan-catechol. This study suggests that glycol chitosan-catechol can be a promising alternative to chitosan-catechol in various biomedical fields such as hemostatic agents.
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Affiliation(s)
- Eunsook Park
- Department of ChemistryKorea Advanced Institute of Science and Technology (KAIST) 291 University Rd Yuseong‐gu Daejeon 34141 Republic of Korea
| | - Jeehee Lee
- Biomedical Science and Engineering Interdisciplinary ProgramKorea Advanced Institute of Science and Technology (KAIST) 291 University Rd Yuseong‐gu Daejeon 34141 Republic of Korea
| | - Kang Moo Huh
- Department of Polymer Science and EngineeringChungnam National University 99 University Rd Yuseong‐gu Daejeon 34134 Republic of Korea
| | - Soo Hyeon Lee
- Department of ChemistryKorea Advanced Institute of Science and Technology (KAIST) 291 University Rd Yuseong‐gu Daejeon 34141 Republic of Korea
| | - Haeshin Lee
- Department of ChemistryKorea Advanced Institute of Science and Technology (KAIST) 291 University Rd Yuseong‐gu Daejeon 34141 Republic of Korea
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20
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Franier BDL, Thompson M. Early stage detection and screening of ovarian cancer: A research opportunity and significant challenge for biosensor technology. Biosens Bioelectron 2019; 135:71-81. [DOI: 10.1016/j.bios.2019.03.041] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 03/04/2019] [Accepted: 03/19/2019] [Indexed: 01/15/2023]
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21
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Fies WA, Dugger JW, Dick JE, Wilder LM, Browning KL, Doucet M, Browning JF, Webb LJ. Direct Measurement of Water Permeation in Submerged Alkyl Thiol Self-Assembled Monolayers on Gold Surfaces Revealed by Neutron Reflectometry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:5647-5662. [PMID: 30919634 DOI: 10.1021/acs.langmuir.9b00541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Self-assembled monolayers (SAMs) of alkyl thiols are frequently used to chemically functionalize gold surfaces for applications throughout materials chemistry, electrochemistry, and biotechnology. Despite this, a detailed understanding of the structure of the SAM-water interface generated from both formation and use of the SAM in an aqueous environment is elusive, and analytical measurements of the structure and chemistry of the SAM-water interface are an ongoing experimental challenge. To address this, we used neutron reflectometry (NR) to measure water association with both hydrophobic and hydrophilic SAMs under both wet and dry conditions. SAMs used for this study were made from hydrophobic decanethiol mixed with hydrophilic 11-azido-1-undecanethiol with compositions of 0-100% of the azide-terminated thiol. All SAMs were formed by conventional solution incubation of a Au substrate immersed in ethanol. Each SAM was characterized by grazing incidence angle reflection-absorption Fourier transfer infrared spectroscopy, contact angle goniometry, and electrochemical methods to confirm it was a completely formed monolayer with evidence of extensive crystalline-like domains. NR measured significant absorption of water into each SAM, ranging from 1.6 to 5.7 water molecules per alkyl thiol, when SAMs were immersed in water. Water infiltration was independent of SAM composition and terminal group hydrophilicity. These results demonstrate that water accesses defects, fluid regions, and heterogeneous domains inherent to even well-formed SAMs.
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Affiliation(s)
- Whitney A Fies
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 2506 Speedway STOP A5300 , Austin , Texas 78712 , United States
| | | | - Jeffrey E Dick
- Department of Chemistry , The University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Logan M Wilder
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 2506 Speedway STOP A5300 , Austin , Texas 78712 , United States
| | | | | | | | - Lauren J Webb
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 2506 Speedway STOP A5300 , Austin , Texas 78712 , United States
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22
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Machado R, Soltani N, Dufour S, Salam MT, Carlen PL, Genov R, Thompson M. Biofouling-Resistant Impedimetric Sensor for Array High-Resolution Extracellular Potassium Monitoring in the Brain. BIOSENSORS 2016; 6:E53. [PMID: 27754393 PMCID: PMC5192373 DOI: 10.3390/bios6040053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 09/28/2016] [Accepted: 09/30/2016] [Indexed: 02/02/2023]
Abstract
Extracellular potassium concentration, [K⁺]o, plays a fundamental role in the physiological functions of the brain. Studies investigating changes in [K⁺]o have predominantly relied upon glass capillary electrodes with K⁺-sensitive solution gradients for their measurements. However, such electrodes are unsuitable for taking spatio-temporal measurements and are limited by the surface area of their tips. We illustrate seizures invoked chemically and in optogenetically modified mice using blue light exposure while impedimetrically measuring the response. A sharp decrease of 1-2 mM in [K⁺]o before each spike has shown new physiological events not witnessed previously when measuring extracellular potassium concentrations during seizures in mice. We propose a novel approach that uses multichannel monolayer coated gold microelectrodes for in vivo spatio-temporal measurements of [K⁺]o in a mouse brain as an improvement to the conventional glass capillary electrode.
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Affiliation(s)
- Ruben Machado
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada.
- Toronto Western Research Institute, Fundamental Neurobiology Division, 60 Leonard Avenue, Toronto, ON M5T 2S8, Canada.
| | - Nima Soltani
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, ON M5S 3G4, Canada.
| | - Suzie Dufour
- Toronto Western Research Institute, Fundamental Neurobiology Division, 60 Leonard Avenue, Toronto, ON M5T 2S8, Canada.
| | - Muhammad Tariqus Salam
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, ON M5S 3G4, Canada.
| | - Peter L Carlen
- Toronto Western Research Institute, Fundamental Neurobiology Division, 60 Leonard Avenue, Toronto, ON M5T 2S8, Canada.
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9, Canada.
| | - Roman Genov
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, ON M5S 3G4, Canada.
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada.
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9, Canada.
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23
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Penna M, Ley K, Maclaughlin S, Yarovsky I. Surface heterogeneity: a friend or foe of protein adsorption – insights from theoretical simulations. Faraday Discuss 2016; 191:435-464. [DOI: 10.1039/c6fd00050a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A lack in the detailed understanding of mechanisms through which proteins adsorb or are repelled at various solid/liquid interfaces limits the capacity to rationally design and produce more sophisticated surfaces with controlled protein adsorption in both biomedical and industrial settings. To date there are three main approaches to achieve anti biofouling efficacy, namely chemically adjusting the surface hydrophobicity and introducing various degrees of surface roughness, or a combination of both. More recently, surface nanostructuring has been shown to have an effect on protein adsorption. However, the current resolution of experimental techniques makes it difficult to investigate these three phase systems at the molecular level. In this molecular dynamics study we explore in all-atom detail the adsorption process of one of the most surface active proteins, EAS hydrophobin, known for its versatile ability to self-assemble on both hydrophobic and hydrophilic surfaces forming stable monolayers that facilitate further biofilm growth. We model the adsorption of this protein on organic ligand protected silica surfaces with varying degrees of chemical heterogeneity and roughness, including fully homogenous hydrophobic and hydrophilic surfaces for comparison. We present a detailed characterisation of the functionalised surface structure and dynamics for each of these systems, and the effect the ligands have on interfacial water, the adsorption process and conformational rearrangements of the protein. Results suggest that the ligand arrangement that produces the highest hydrophilic chain mobility and the lack of significant hydrophobic patches shows the most promising anti-fouling efficacy toward hydrophobin. However, the presence on the protein surface of a flexible loop with amphipathic character (the Cys3–Cys4 loop) is seen to facilitate EAS adsorption on all surfaces by enabling the protein to match the surface pattern.
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Affiliation(s)
- Matthew Penna
- School of Engineering
- RMIT University
- Melbourne
- Australia
- ARC Research Hub for Australian Steel Manufacturing
| | - Kamron Ley
- School of Engineering
- RMIT University
- Melbourne
- Australia
| | - Shane Maclaughlin
- BlueScope Steel Research Laboratories
- Port Kembla
- Australia
- ARC Research Hub for Australian Steel Manufacturing
- Australia
| | - Irene Yarovsky
- School of Engineering
- RMIT University
- Melbourne
- Australia
- ARC Research Hub for Australian Steel Manufacturing
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24
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Kostina NY, Pop-Georgievski O, Bachmann M, Neykova N, Bruns M, Michálek J, Bastmeyer M, Rodriguez-Emmenegger C. Non-Fouling Biodegradable Poly(ϵ-caprolactone) Nanofibers for Tissue Engineering. Macromol Biosci 2015; 16:83-94. [DOI: 10.1002/mabi.201500252] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 09/15/2015] [Indexed: 12/16/2022]
Affiliation(s)
- Nina Yu. Kostina
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i., Heyrovsky sq.2 Prague 162 06 Czech Republic
| | - Ognen Pop-Georgievski
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i., Heyrovsky sq.2 Prague 162 06 Czech Republic
| | - Michael Bachmann
- Zoological Institute; Cell and Neurobiology; Karlsruhe Institute of Technology (KIT); Haid-und-Neu-Straße 9 Karlsruhe 76131 Germany
| | - Neda Neykova
- Institute of Physics; Academy of Sciences of the Czech Republic; Cukrovarnicka 10 Prague 16253 Czech Republic
- Faculty of Nuclear Science and Physical Engineering; Czech Technical University in Prague; Trojanova 13 Prague 12000 Czech Republic
| | - Michael Bruns
- Institute for Applied Materials (IAM) and Karlsruhe Nano Micro Facility (KNMF); Karlsruhe Institute of Technology (KIT); Hermann-von-Helmholtz-Platz 1 Eggenstein-Leopoldshafen 76344 Germany
| | - Jiří Michálek
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i., Heyrovsky sq.2 Prague 162 06 Czech Republic
| | - Martin Bastmeyer
- Zoological Institute; Cell and Neurobiology; Karlsruhe Institute of Technology (KIT); Haid-und-Neu-Straße 9 Karlsruhe 76131 Germany
- Institute for Functional Interfaces (IFG) Karlsruhe Institute of Technology (KIT); Hermann-von-Helmholtz-Platz 1; Eggenstein-Leopoldshafen 76344 Germany
| | - Cesar Rodriguez-Emmenegger
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i., Heyrovsky sq.2 Prague 162 06 Czech Republic
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25
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Fedorov K, Jankowski A, Sheikh S, Blaszykowski C, Reheman A, Romaschin A, Ni H, Thompson M. Prevention of surface-induced thrombogenesis on poly(vinyl chloride). J Mater Chem B 2015; 3:8623-8628. [PMID: 32262718 DOI: 10.1039/c5tb01582k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Much biomedical equipment consisting of or containing plastic polymer(s) must come into contact with blood - an interaction that, at the molecular level, may unfortunately prompt biological processes with potentially deleterious, short- or long-term effects such as thrombosis. In the present investigation, this problem is alleviated for poly(vinyl chloride) (PVC) through chemical surface modification with an ultrathin, monoethylene glycol-based coating - a transformation that is characterized using X-ray photoelectron spectroscopy (XPS) supplemented by contact angle goniometry (CAG). Antithrombogenic properties are assessed through calculation (for the first 10 min, and after 60 min) of the surface coverage percentage due to platelet adhesion, aggregation and thrombus formation upon continuous exposure to fluorescently-labelled whole human blood. At all shear rates investigated (300, 900, and 1500 s-1), surface coverage decreases by >99% with respect to bare PVC (10 min, short-term contact with blood). Most importantly, antithrombogenic performance is retained for longer-term exposure experiments (60 min), regardless of applied shear rate as well.
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Affiliation(s)
- Kiril Fedorov
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario M5S 3G9, Canada.
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26
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Machado R, Blaszykowski C, Sheikh S, Suganuma Y, Thompson M. Ultrathin Surface Chemistry to Delay Anion Fouling. Chempluschem 2015; 80:911-914. [PMID: 31973268 DOI: 10.1002/cplu.201500027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 02/17/2015] [Indexed: 11/07/2022]
Abstract
The unwanted fouling of surfaces by ionic adsorption has received little research attention. In this context, ultrathin organic adlayer surface chemistry-featuring monoethylene glycol based molecular residues-is described that is capable of noticeably decreasing the rate of anion depletion from solution. The strategy is exemplified with glass as the substrate material and fluoride as the anion foulant.
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Affiliation(s)
- Ruben Machado
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6 (Canada), Fax: (+1) 416 978 8775
| | | | - Sonia Sheikh
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6 (Canada), Fax: (+1) 416 978 8775
| | - Yoshinori Suganuma
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6 (Canada), Fax: (+1) 416 978 8775
| | - Michael Thompson
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6 (Canada), Fax: (+1) 416 978 8775.,Econous Systems Inc. 80 St. George Street, Toronto, ON M5S 3H6 (Canada).,Institute of Biomaterials & Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9 (Canada)
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27
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Surman F, Riedel T, Bruns M, Kostina NY, Sedláková Z, Rodriguez-Emmenegger C. Polymer Brushes Interfacing Blood as a Route Toward High Performance Blood Contacting Devices. Macromol Biosci 2015; 15:636-46. [DOI: 10.1002/mabi.201400470] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 11/28/2014] [Indexed: 12/31/2022]
Affiliation(s)
- František Surman
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i. Prague 162 06 Czech Republic
| | - Tomáš Riedel
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i. Prague 162 06 Czech Republic
| | - Michael Bruns
- Institute for Applied Materials (IAM); Karlsruhe Nano Micro Facility (KNMF); Karlsruhe Institute of Technology (KIT); Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
| | - Nina Yu. Kostina
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i. Prague 162 06 Czech Republic
| | - Zdeňka Sedláková
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i. Prague 162 06 Czech Republic
| | - Cesar Rodriguez-Emmenegger
- Institute of Macromolecular Chemistry; Academy of Sciences of the Czech Republic; v.v.i. Prague 162 06 Czech Republic
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28
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On the hydration of subnanometric antifouling organosilane adlayers: a molecular dynamics simulation. J Colloid Interface Sci 2014; 437:197-204. [PMID: 25313484 DOI: 10.1016/j.jcis.2014.09.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/10/2014] [Accepted: 09/11/2014] [Indexed: 12/20/2022]
Abstract
The connection between antifouling and surface hydration is a fascinating but daunting question to answer. Herein, we use molecular dynamics (MD) computer simulations to gain further insight into the role of surface functionalities in the molecular-level structuration of water (surface kosmotropicity)--within and atop subnanometric organosilane adlayers that were shown in previous experimental work to display varied antifouling behavior. Our simulations support the hypothesized intimate link between surface hydration and antifouling, in particular the importance of both internal and interfacial hydrophilicity and kosmotropicity. The antifouling mechanism is also discussed in terms of surface dehydration energy and water dynamicity (lability and mobility), notably the crucial requirement for clustered water molecules to remain tightly bound for extensive periods of time--i.e. exhibit slow exchange dynamics. A substrate effect on surface hydration, which would also participate in endowing antifouling adlayers with hydrogel-like characteristics, is also proposed. In contrast, the role of adlayer flexibility, if any, is assigned a secondary role in these ultrathin structures made of short building blocks. The conclusions from this work are well in line with those previously drawn in the literature.
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