1
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Effect of poly(ethylene glycol) methacrylate on the ophthalmic properties of silicone hydrogel contact lenses. Colloids Surf B Biointerfaces 2022. [DOI: 10.1016/j.colsurfb.2022.112713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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2
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Santi M, Saha P, Walkowiak JJ, Rubner J, Wessling M, Pich A. In-Line Characterization of the Temperature-Responsive Behavior of Surface-Bound Microgel Coatings by QCM-D: A Novel Strategy for Protein Repellence Evaluation. ACS APPLIED MATERIALS & INTERFACES 2022; 14:10907-10916. [PMID: 35179345 DOI: 10.1021/acsami.1c21814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this work, quartz crystal microbalance with dissipation monitoring (QCM-D) was used to develop a new method to evaluate the protein repellency of microgel coatings. Compared to traditional protocols for surface analysis, QCM has the advantage of a real-time quantitative approach with high sensitivity, allowing us to describe variations of the adsorbed mass with unprecedented accuracy. To enable the detectability of the film throughout the whole operational temperature interval, a poly(N-isopropylacrylamide-co-glycidyl methacrylate) p(NIPAm-co-GMA) microgel monolayer with defined thickness and rigidity was designed. Covalent adhesion of the film to the silica surface was achieved by epoxy-thiol click chemistry and tested for repeated temperature cycles, showing substantial reproducibility. Further functionalization of microgel surfaces by grafting polyzwitterionic chains remarkably improved the protein repellence leaving the strong surface adhesion unaltered. Before and after exposure to fluorescein-tagged bovine serum albumin (FITC-BSA), the coatings showed identical responsive behavior, proving the absence of protein deposition. In nonrepellent coatings, QCM monitoring instead displayed a characteristic shift in the volume phase transition (VPT), pointing out the effect of adsorbed proteins on the swelling behavior of pNIPAm. The combination of QCM-D and UV-visible (UV-vis) was used to evaluate the effect of increasing surface coverage, enabling to distinguish between the protein deposition occurring over the coated and the uncoated portion of the sensor.
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Affiliation(s)
- Marta Santi
- DWI - Leibniz-Institute for Interactive Materials, Aachen 52074, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Aachen 52074, Germany
| | - Pabitra Saha
- DWI - Leibniz-Institute for Interactive Materials, Aachen 52074, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Aachen 52074, Germany
| | - Jacek Janusz Walkowiak
- DWI - Leibniz-Institute for Interactive Materials, Aachen 52074, Germany
- Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Geleen 6167 RD, the Netherlands
| | - Jens Rubner
- Chemical Process Engineering AVT.CVT, RWTH Aachen University, Aachen 52074, Germany
| | - Matthias Wessling
- DWI - Leibniz-Institute for Interactive Materials, Aachen 52074, Germany
- Chemical Process Engineering AVT.CVT, RWTH Aachen University, Aachen 52074, Germany
| | - Andrij Pich
- DWI - Leibniz-Institute for Interactive Materials, Aachen 52074, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Aachen 52074, Germany
- Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Geleen 6167 RD, the Netherlands
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3
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Gegenschatz-Schmid K, Buzzi S, Grossmann J, Roschitzki B, Urbanet R, Heuberger R, Glück D, Zucker A, Ehrbar M. Reduced thrombogenicity of surface-treated Nitinol implants steered by altered protein adsorption. Acta Biomater 2022; 137:331-345. [PMID: 34673227 DOI: 10.1016/j.actbio.2021.10.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 10/11/2021] [Accepted: 10/13/2021] [Indexed: 12/19/2022]
Abstract
Blood-contacting medical implants made of Nitinol and other titanium alloys, such as neurovascular flow diverters and peripheral stents, have the disadvantage of being highly thrombogenic. This makes the use of systemic (dual) anti-platelet/anticoagulant therapies inevitable with related risks of device thrombosis, bleeding and other complications. Meeting the urgent clinical demand for a less thrombogenic Nitinol surface, we describe here a simple treatment of standard, commercially available Nitinol that renders its surface ultra-hydrophilic and functionalized with phosphate ions. The efficacy of this treatment was assessed by comparing standard and surface-treated Nitinol disks and braids, equivalent to flow diverters. Static and dynamic (Chandler loop) blood incubation tests showed a drastic reduction of thrombus formation on treated devices. Surface chemistry and proteomic analysis indicated a key role of phosphate and calcium ions in steering blood protein adsorption and avoiding coagulation cascade activation and platelet adhesion. A good endothelialization of the surface confirmed the biocompatibility of the treated surface. STATEMENT OF SIGNIFICANCE: Titanium alloys such as Nitinol are biocompatible and show favorable mechanical properties, which led to their widespread use in medical implants. However, in contact with blood their surface triggers the activation of the intrinsic coagulation cascade, which may result in catastrophic thrombotic events. The presented results showed that a phosphate functionalization of the titanium oxide surface suppresses the activation of both coagulation cascade and platelets, avoiding the subsequent formation of a blood clot. This novel approach has therefore a great potential for mitigating the risks associated to either thrombosis or bleeding complications (due to systemic anticoagulation) in patients with cardiovascular implants.
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4
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Jesmer AH, Huynh V, Marple AST, Ding X, Moran-Mirabal JM, Wylie RG. Graft-Then-Shrink: Simultaneous Generation of Antifouling Polymeric Interfaces and Localized Surface Plasmon Resonance Biosensors. ACS APPLIED MATERIALS & INTERFACES 2021; 13:52362-52373. [PMID: 34704743 DOI: 10.1021/acsami.1c14930] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Antifouling polymer coatings that are simple to manufacture are crucial for the performance of medical devices such as biosensors. "Grafting-to", a simple technique where presynthesized polymers are immobilized onto surfaces, is commonly employed but suffers from nonideal polymer packing leading to increased biofouling. Herein, we present a material prepared via the grafting-to method with improved antifouling surface properties and intrinsic localized surface plasmon resonance (LSPR) sensor capabilities. A new substrate shrinking fabrication method, Graft-then-Shrink, improved the antifouling properties of polymer-coated Au surfaces by altering graft-to polymer packing while simultaneously generating wrinkled Au structures for LSPR biosensing. Thiol-terminated, antifouling, hydrophilic polymers were grafted to Au-coated prestressed polystyrene (PS) followed by shrinking upon heating above the PS glass transition temperature. Interestingly, the polymer molecular weight and hydration influenced Au wrinkling patterns. Compared to Shrink-then-Graft controls, where polymers are immobilized post shrinking, Graft-then-Shrink increased the polymer content by 76% in defined footprints and improved the antifouling properties as demonstrated by 84 and 72% reduction in macrophage adhesion and protein adsorption, respectively. Wrinkled Au LSPR sensors had sensitivities of ∼200-1000 Δλ/ΔRIU, comparing favorably to commercial LSPR sensors, and detected biotin-avidin and desthiobiotin-avidin complexation in a concentration-dependent manner using a standard plate reader and a 96-well format.
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Affiliation(s)
- Alexander H Jesmer
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Vincent Huynh
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - April S T Marple
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Xiuping Ding
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Jose M Moran-Mirabal
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Ryan G Wylie
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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5
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Choe JC, Park JH, Lee HC, Park TS, Ahn J, Park JS, Lee HW, Oh JH, Choi JH, Cha KS, Yim C, Jeon S. Histopathologic response after hydrophilic polyethylene glycol-coating stent and hydrophobic octadecylthiol-coating stent implantations in porcine coronary restenosis model. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2020; 31:122. [PMID: 33247775 DOI: 10.1007/s10856-020-06452-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 12/07/2019] [Accepted: 10/27/2020] [Indexed: 06/12/2023]
Abstract
Device-related problems of drug-eluting stents, including stent thrombosis related to antiproliferative drugs and polymers, can cause adverse events such as inflammation and neointimal hyperplasia. Stent surface modification, wherein the drug and polymer are not required, may overcome these problems. We developed hydrophilic polyethylene glycol (PEG)-coating and hydrophobic octadecylthiol (ODT)-coating stents without a drug and polymer and evaluated their histopathologic response in a porcine coronary restenosis model. PEG-coating stents (n = 12), bare-metal stents (BMS) (n = 12), and ODT-coating stents (n = 10) were implanted with oversizing in 34 porcine coronary arteries. Four weeks later, the histopathologic response, arterial injury, inflammation, and fibrin scores were analyzed. A p value < 0.05 was considered statistically significant. There were significant differences in the internal elastic lamina area, lumen area, neointimal area, percent area of stenosis, arterial injury score, inflammation score, and fibrin score among the groups. Compared to the BMS or ODT-coating stent group, the PEG-coating stent group had significantly increased internal elastic lamina and lumen area (all p < 0.001) and decreased neointimal area and percent area of stenosis (BMS: p = 0.03 and p < 0.001, respectively; ODT-coating: p = 0.013 and p < 0.001, respectively). Similarly, the PEG-coating group showed significantly lower inflammation and fibrin scores than the BMS or ODT-coating groups (BMS: p = 0.013 and p = 0.007, respectively; ODT-coating: p = 0.014 and p = 0.008, respectively). In conclusion, hydrophilic PEG-coating stent implantation was associated with lower inflammatory response, decreased fibrin deposition, and reduced neointimal hyperplasia than BMS or hydrophobic ODT-coating stent implantation in the porcine coronary restenosis model.
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Affiliation(s)
- Jeong Cheon Choe
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Jong Ha Park
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Han Cheol Lee
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea.
| | - Tae Sik Park
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Jinhee Ahn
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Jin Sup Park
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Hye Won Lee
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Jun-Hyok Oh
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Jung Hyun Choi
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Kwang Soo Cha
- Division of Cardiology, Medical Research Institute, Department of Internal Medicine, Pusan National University Hospital, Busan, Republic of Korea
| | - Changyong Yim
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Sangmin Jeon
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
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6
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Keskin D, Mergel O, van der Mei HC, Busscher HJ, van Rijn P. Inhibiting Bacterial Adhesion by Mechanically Modulated Microgel Coatings. Biomacromolecules 2019; 20:243-253. [PMID: 30512925 PMCID: PMC6335679 DOI: 10.1021/acs.biomac.8b01378] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/02/2018] [Indexed: 02/06/2023]
Abstract
Bacterial infection is a severe problem especially when associated with biomedical applications. This study effectively demonstrates that poly- N-isopropylmethacrylamide based microgel coatings prevent bacterial adhesion. The coating preparation via a spraying approach proved to be simple and both cost and time efficient creating a homogeneous dense microgel monolayer. In particular, the influence of cross-linking density, microgel size, and coating thickness was investigated on the initial bacterial adhesion. Adhesion of Staphylococcus aureus ATCC 12600 was imaged using a parallel plate flow chamber setup, which gave insights in the number of the total bacteria adhering per unit area onto the surface and the initial bacterial deposition rates. All microgel coatings successfully yielded more than 98% reduction in bacterial adhesion. Bacterial adhesion depends both on the cross-linking density/stiffness of the microgels and on the thickness of the microgel coating. Bacterial adhesion decreased when a lower cross-linking density was used at equal coating thickness and at equal cross-linking density with a thicker microgel coating. The highest reduction in the number of bacterial adhesion was achieved with the microgel that produced the thickest coating ( h = 602 nm) and had the lowest cross-linking density. The results provided in this paper indicate that microgel coatings serve as an interesting and easy applicable approach and that it can be fine-tuned by manipulating the microgel layer thickness and stiffness.
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Affiliation(s)
- Damla Keskin
- University
of Groningen, University Medical Center Groningen, Department of Biomedical
Engineering (FB40), W.J. Kolff Institute
for Biomedical Engineering and Materials Science (FB41), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Olga Mergel
- University
of Groningen, University Medical Center Groningen, Department of Biomedical
Engineering (FB40), W.J. Kolff Institute
for Biomedical Engineering and Materials Science (FB41), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Henny C. van der Mei
- University
of Groningen, University Medical Center Groningen, Department of Biomedical
Engineering (FB40), W.J. Kolff Institute
for Biomedical Engineering and Materials Science (FB41), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Henk J. Busscher
- University
of Groningen, University Medical Center Groningen, Department of Biomedical
Engineering (FB40), W.J. Kolff Institute
for Biomedical Engineering and Materials Science (FB41), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Patrick van Rijn
- University
of Groningen, University Medical Center Groningen, Department of Biomedical
Engineering (FB40), W.J. Kolff Institute
for Biomedical Engineering and Materials Science (FB41), Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
- University of
Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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7
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Tang L, Zheng Y, Melo MB, Mabardi L, Castaño AP, Xie YQ, Li N, Kudchodkar SB, Wong HC, Jeng EK, Maus MV, Irvine DJ. Enhancing T cell therapy through TCR-signaling-responsive nanoparticle drug delivery. Nat Biotechnol 2018; 36:707-716. [PMID: 29985479 PMCID: PMC6078803 DOI: 10.1038/nbt.4181] [Citation(s) in RCA: 406] [Impact Index Per Article: 67.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 06/07/2018] [Indexed: 12/24/2022]
Abstract
Adoptive cell therapy (ACT) with antigen-specific T cells has shown remarkable clinical success, but approaches to safely and effectively augment T cell function, especially in solid tumors, remain of great interest. Here we describe a strategy to “backpack” large quantities of supporting protein drugs on T cells using protein nanogels (NGs) that selectively release these cargos in response to T cell receptor (TCR) activation. We design cell surface-conjugated NGs that respond to an increase in T cell surface reduction potential upon antigen recognition, limiting drug release to sites of antigen encounter such as the tumor microenvironment. Using NGs carrying an IL-15 superagonist complex, we demonstrate that relative to systemic administration of free cytokines, NG delivery selectively expands T cells 16-fold in tumors, and allows at least 8-fold higher doses of cytokine to be administered without toxicity. The improved therapeutic window enables substantially increased tumor clearance by murine T cell and human CAR-T cell therapy in vivo.
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Affiliation(s)
- Li Tang
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA.,Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Yiran Zheng
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Mariane Bandeira Melo
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Llian Mabardi
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA
| | - Ana P Castaño
- Cellular Immunotherapy Program, Massachusetts General Hospital (MGH) Cancer Center, Charlestown, Massachusetts, USA
| | - Yu-Qing Xie
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Na Li
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | | | - Hing C Wong
- Altor BioScience Corporation, Miramar, Florida, USA
| | - Emily K Jeng
- Altor BioScience Corporation, Miramar, Florida, USA
| | - Marcela V Maus
- Cellular Immunotherapy Program, Massachusetts General Hospital (MGH) Cancer Center, Charlestown, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Darrell J Irvine
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA.,Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.,Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
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8
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Covalent Immobilization of Enoxacin onto Titanium Implant Surfaces for Inhibiting Multiple Bacterial Species Infection and In Vivo Methicillin-Resistant Staphylococcus aureus Infection Prophylaxis. Antimicrob Agents Chemother 2016; 61:AAC.01766-16. [PMID: 27799220 DOI: 10.1128/aac.01766-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 10/25/2016] [Indexed: 12/19/2022] Open
Abstract
Infection is one of the most important causes of titanium implant failure in vivo A developing prophylactic method involves the immobilization of antibiotics, especially vancomycin, onto the surface of the titanium implant. However, these methods have a limited effect in curbing multiple bacterial infections due to antibiotic specificity. In the current study, enoxacin was covalently bound to an amine-functionalized Ti surface by use of a polyethylene glycol (PEG) spacer, and the bactericidal effectiveness was investigated in vitro and in vivo The titanium surface was amine functionalized with 3-aminopropyltriethoxysilane (APTES), through which PEG spacer molecules were covalently immobilized onto the titanium, and then the enoxacin was covalently bound to the PEG, which was confirmed by X-ray photoelectron spectrometry (XPS). A spread plate assay, confocal laser scanning microscopy (CLSM), and scanning electron microscopy (SEM) were used to characterize the antimicrobial activity. For the in vivo study, Ti implants were inoculated with methicillin-resistant Staphylococcus aureus (MRSA) and implanted into the femoral medullary cavity of rats. The degree of infection was assessed by radiography, micro-computed tomography, and determination of the counts of adherent bacteria 3 weeks after surgery. Our data demonstrate that the enoxacin-modified PEGylated Ti surface effectively prevented bacterial colonization without compromising cell viability, adhesion, or proliferation in vitro Furthermore, it prevented MRSA infection of the Ti implants in vivo Taken together, our results demonstrate that the use of enoxacin-modified Ti is a potential approach to the alleviation of infections of Ti implants by multiple bacterial species.
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9
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Nyström L, Malmsten M. Surface-bound microgels - From physicochemical properties to biomedical applications. Adv Colloid Interface Sci 2016; 238:88-104. [PMID: 27865424 DOI: 10.1016/j.cis.2016.11.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/02/2016] [Accepted: 11/04/2016] [Indexed: 12/18/2022]
Abstract
Microgels offer robust and facile approaches for surface modification, as well as opportunities to introduce biological functionality by loading such structures with bioactive agents, e.g., in the context of drug delivery, functional biomaterials, and biosensors. As such, they provide a versatile approach for the design of surfaces with pre-determined characteristics compared to more elaborate bottom-up approaches, such as layer-by-layer deposition and surface-initiated polymerization. In the present overview, properties of surface-bound microgels are discussed, ranging from physical adsorption and covalent grafting in dilute systems, to directed self-assembly, multilayer structures, and composites, as well as loading an release of drugs and other cargo molecules into/from such systems, and biomedical applications of these.
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10
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Zhang Y, Zhang J, Xing C, Zhang M, Wang L, Zhao H. Protein Nanogels with Temperature-Induced Reversible Structures and Redox Responsiveness. ACS Biomater Sci Eng 2016; 2:2266-2275. [DOI: 10.1021/acsbiomaterials.6b00490] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Yue Zhang
- Key
Laboratory of Functional Polymer Materials, Ministry of Education,
College of Chemistry, Nankai University, Tianjin 300071, China
- Collaborative
Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
| | - Jiamin Zhang
- The
Key Laboratory of Bioactive Materials, Ministry of Education, College
of Life Sciences, Nankai University, Tianjin 300071, China
| | - Cheng Xing
- The
Key Laboratory of Bioactive Materials, Ministry of Education, College
of Life Sciences, Nankai University, Tianjin 300071, China
| | - Mingming Zhang
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China
| | - Lianyong Wang
- The
Key Laboratory of Bioactive Materials, Ministry of Education, College
of Life Sciences, Nankai University, Tianjin 300071, China
| | - Hanying Zhao
- Key
Laboratory of Functional Polymer Materials, Ministry of Education,
College of Chemistry, Nankai University, Tianjin 300071, China
- Collaborative
Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China
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11
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Sivakumaran D, Mueller E, Hoare T. Temperature-Induced Assembly of Monodisperse, Covalently Cross-Linked, and Degradable Poly(N-isopropylacrylamide) Microgels Based on Oligomeric Precursors. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:5767-5778. [PMID: 25977976 DOI: 10.1021/acs.langmuir.5b01421] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A simple, rapid, solvent-free, and scalable thermally driven self-assembly approach is described to produce monodisperse, covalently cross-linked, and degradable poly(N-isopropylacrylamide) (PNIPAM) microgels based on mixing hydrazide (PNIPAM-Hzd) and aldehyde (PNIPAM-Ald) functionalized PNIPAM precursors. Preheating of a seed PNIPAM-Hzd solution above its phase transition temperature produces nanoaggregates that are subsequently stabilized and cross-linked by the addition of PNIPAM-Ald. The ratio of PNIPAM-Hzd:PNIPAM-Ald used to prepare the microgels, the time between PNIPAM-Ald addition and cooling, the temperature to which the PNIPAM-Hzd polymer solution is preheated, and the concentration of PNIPAM-Hzd in the initial seed solution can all be used to control the size of the resulting microgels. The microgels exhibit similar thermal phase transition behavior to conventional precipitation-based microgels but are fully degradable into oligomeric precursor polymers. The microgels can also be lyophilized and redispersed without any change in colloidal stability or particle size and exhibit no significant cytotoxicity in vitro. We anticipate that microgels fabricated using this approach may facilitate translation of the attractive properties of such microgels in vivo without the concerns regarding microgel clearance that exist with other PNIPAM-based microgels.
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Affiliation(s)
- Daryl Sivakumaran
- Department of Chemical Engineering, McMaster University, 1280 Main St. W, Hamilton, Ontario, Canada L8S 4L7
| | - Eva Mueller
- Department of Chemical Engineering, McMaster University, 1280 Main St. W, Hamilton, Ontario, Canada L8S 4L7
| | - Todd Hoare
- Department of Chemical Engineering, McMaster University, 1280 Main St. W, Hamilton, Ontario, Canada L8S 4L7
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12
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Jeong KS, Kim HJ, Lim HL, Ryu GC, Seo ES, You NH, Jun J. Synthesis and Biocompatibility of Silicone Hydrogel Functionalized with Polysaccharide. B KOREAN CHEM SOC 2015. [DOI: 10.1002/bkcs.10315] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Keun-Seung Jeong
- Department of Optometry and Optic Science; Dongshin University; Naju 520-714 Korea
| | - Ho-Joong Kim
- Department of Chemistry; Chosun University; Gwangju 501-759 Korea
| | - Hwa-Lim Lim
- Department of Optometry and Optic Science; Dongshin University; Naju 520-714 Korea
| | - Geun-Chang Ryu
- Department of Optometry and Optic Science; Dongshin University; Naju 520-714 Korea
| | - Eun-Sun Seo
- Department of Optometry and Optic Science; Dongshin University; Naju 520-714 Korea
| | - Nam-Ho You
- Carbon Convergence Materials Research Center; Institute of Advanced Composites Materials, Korea Institute of Science and Technology; Wanju-gun 565-905 Korea
| | - Jin Jun
- Department of Optometry and Optic Science; Dongshin University; Naju 520-714 Korea
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13
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Kim HJ, Ryu GC, Jeong KS, Jun J. Hydrogel lenses functionalized with polysaccharide for reduction of protein adsorption. Macromol Res 2014. [DOI: 10.1007/s13233-015-3009-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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Wilson KA, Finch CA, Anderson P, Vollmer F, Hickman JJ. Combining an optical resonance biosensor with enzyme activity kinetics to understand protein adsorption and denaturation. Biomaterials 2014; 38:86-96. [PMID: 25453976 DOI: 10.1016/j.biomaterials.2014.10.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/02/2014] [Indexed: 11/30/2022]
Abstract
Understanding protein adsorption and resultant conformation changes on modified and unmodified silicon dioxide surfaces is a subject of keen interest in biosensors, microfluidic systems and for medical diagnostics. However, it has been proven difficult to investigate the kinetics of the adsorption process on these surfaces as well as understand the topic of the denaturation of proteins and its effect on enzyme activity. A highly sensitive optical whispering gallery mode (WGM) resonator was used to study a catalytic enzyme's adsorption processes on different silane modified glass substrates (plain glass control, DETA, 13 F, and SiPEG). The WGM sensor was able to obtain high resolution kinetic data of glucose oxidase (GO) adsorption with sensitivity of adsorption better than that possible with SPR. The kinetic data, in combination with a functional assay of the enzyme activity, was used to test hypotheses on adsorption mechanisms. By fitting numerical models to the WGM sensograms for protein adsorption, and by confirming numerical predictions of enzyme activity in a separate assay, we were able to identify mechanisms for GO adsorption on different alkylsilanes and infer information about the adsorption of protein on nanostructured surfaces.
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Affiliation(s)
- Kerry A Wilson
- Nanoscience Technology Center, University of Central Florida, 12424 Research Parkway, Orlando, FL 32826, USA
| | - Craig A Finch
- Nanoscience Technology Center, University of Central Florida, 12424 Research Parkway, Orlando, FL 32826, USA
| | - Phillip Anderson
- Nanoscience Technology Center, University of Central Florida, 12424 Research Parkway, Orlando, FL 32826, USA
| | - Frank Vollmer
- The Wyss & Rowland Institutes, Harvard University, 100 Edwin H. Land Blvd, Cambridge, MA 02142, USA
| | - James J Hickman
- Nanoscience Technology Center, University of Central Florida, 12424 Research Parkway, Orlando, FL 32826, USA.
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Biomimetic modified clinical-grade POSS-PCU nanocomposite polymer for bypass graft applications: a preliminary assessment of endothelial cell adhesion and haemocompatibility. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2014; 46:400-8. [PMID: 25492004 DOI: 10.1016/j.msec.2014.10.065] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/25/2014] [Accepted: 10/21/2014] [Indexed: 01/26/2023]
Abstract
BACKGROUND To date, there are no small internal diameter (<5mm) vascular grafts that are FDA approved for clinical use due to high failure rates from thrombosis and unwanted cell proliferation. The ideal conditions to enhance bioengineered grafts would be the blood contacting lumen of the bypass graft fully covered by endothelial cells (ECs). As a strategy towards this aim, we hypothesized that by immobilising biomolecules on the surface of the polyhedral oligomeric silsesquioxane-poly(carbonate-urea)urethane (POSS-PCU) nanocomposite polymers, which contain binding sites and ligands for cell surface receptors similar to extracellular matrix (ECM) will positively influence the attachment and proliferation of ECs. Since, the surface of POSS-PCU is inert and not directly suitable for immobilisation of biomolecules, plasma graft polymerisation is a suitable method to modify the surface properties ready for immobilisation and biofunctionalisation. METHODS POSS-PCU was activated by plasma treatment in air/O2 to from hydroperoxides (-OH, -OOH), and then carboxylated via plasma polymerisation of a 30% acrylic acid solution (Poly-AA) using a two-step plasma treatment (TSPT) process. Collagen type I, a major component of ECM, was covalently immobilised to mimic the ECM structures to ECs (5mg/ml) using a two-step chemical reaction using EDC chemistry. Successful immobilisation of poly-AA and collagen on to the nanocomposites was confirmed using Toluidine Blue staining and the Bradford assay. Un-treated POSS-PCU served as a simple control. The impact of collagen grafting on the physical, mechanical and biological properties of POSS-PCU was evaluated via contact angle (θ) measurements, scanning electron microscopy (SEM), atomic force microscopy (AFM), dynamic mechanical thermal analysis (DMTA), ECs adhesion and proliferation followed by platelet adhesion and haemolysis ratio (HR) tests. RESULTS Poly-AA content on each of the plasma treated nanocomposite films increased on Low, Med and High samples due to more carboxylic acid (-COOH) groups at the surface forming amide (-NH2) bonds. The amount of -COOH groups on each of the Low, Med and High nanocomposites correlated with Poly-AA grafting density at 14.7±0.9, 18.9±0.9, and 34.2±2.4 μg/cm(2). Immobilisation of collagen type I on to nanocomposite surface was also found to increase significantly on the Low, Med and High samples from 22±4, 150±15, and 219±17 μg/cm(2), respectively. The level of ECs and their adhesion efficiency were improved with increasing amounts of grafted collagen I. The maximum adhesion of ECs was found on the highest collagen type I coated nanocomposites. Platelet adhesion and activation also increased with increasing collagen density. The obtained HR values for all of the treated samples were well within the acceptable standards for biomaterials (<5% HR). CONCLUSION Poly-AA-g-POSS-PCU surfaces offer binding sites for the covalent bonding of collagen type I and other biomolecules such as fibronectin by exposure of RGD cell binding domains and growth factors using EDC cross-linking chemistry. Collagen type I modification can yield accelerated EC growth and enhance the endothelialisation of POSS-PCU nanocomposites, and the amount of immobilised collagen can control the level of platelet adhesion on functionalized POSS-PCU via TSPT and poly acrylic acid (poly-AA) treatment. Such surface modification procedures of polymeric surfaces can improve the patency rate of POSS-PCU nanocomposites as vascular bypass grafts in the preparation of a range of medical devices ready for pre-clinical and in vivo evaluation.
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Gust A, Zander A, Gietl A, Holzmeister P, Schulz S, Lalkens B, Tinnefeld P, Grohmann D. A starting point for fluorescence-based single-molecule measurements in biomolecular research. Molecules 2014; 19:15824-65. [PMID: 25271426 PMCID: PMC6271140 DOI: 10.3390/molecules191015824] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/17/2014] [Accepted: 09/17/2014] [Indexed: 01/24/2023] Open
Abstract
Single-molecule fluorescence techniques are ideally suited to provide information about the structure-function-dynamics relationship of a biomolecule as static and dynamic heterogeneity can be easily detected. However, what type of single-molecule fluorescence technique is suited for which kind of biological question and what are the obstacles on the way to a successful single-molecule microscopy experiment? In this review, we provide practical insights into fluorescence-based single-molecule experiments aiming for scientists who wish to take their experiments to the single-molecule level. We especially focus on fluorescence resonance energy transfer (FRET) experiments as these are a widely employed tool for the investigation of biomolecular mechanisms. We will guide the reader through the most critical steps that determine the success and quality of diffusion-based confocal and immobilization-based total internal reflection fluorescence microscopy. We discuss the specific chemical and photophysical requirements that make fluorescent dyes suitable for single-molecule fluorescence experiments. Most importantly, we review recently emerged photoprotection systems as well as passivation and immobilization strategies that enable the observation of fluorescently labeled molecules under biocompatible conditions. Moreover, we discuss how the optical single-molecule toolkit has been extended in recent years to capture the physiological complexity of a cell making it even more relevant for biological research.
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Affiliation(s)
- Alexander Gust
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany
| | - Adrian Zander
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany
| | - Andreas Gietl
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany
| | - Phil Holzmeister
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany
| | - Sarah Schulz
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany
| | - Birka Lalkens
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany
| | - Philip Tinnefeld
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany
| | - Dina Grohmann
- Physikalische und Theoretische Chemie - NanoBioSciences, Technische Universität Braunschweig, Hans-Sommer-Strasse 10, Braunschweig 38106, Germany.
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Schönwälder SMS, Bally F, Heinke L, Azucena C, Bulut ÖD, Heißler S, Kirschhöfer F, Gebauer TP, Neffe AT, Lendlein A, Brenner-Weiß G, Lahann J, Welle A, Overhage J, Wöll C. Interaction of human plasma proteins with thin gelatin-based hydrogel films: a QCM-D and ToF-SIMS study. Biomacromolecules 2014; 15:2398-406. [PMID: 24956040 PMCID: PMC4215905 DOI: 10.1021/bm500750v] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In the fields of surgery and regenerative medicine, it is crucial to understand the interactions of proteins with the biomaterials used as implants. Protein adsorption directly influences cell-material interactions in vivo and, as a result, regulates, for example, cell adhesion on the surface of the implant. Therefore, the development of suitable analytical techniques together with well-defined model systems allowing for the detection, characterization, and quantification of protein adsorbates is essential. In this study, a protocol for the deposition of highly stable, thin gelatin-based films on various substrates has been developed. The hydrogel films were characterized morphologically and chemically. Due to the obtained low thickness of the hydrogel layer, this setup allowed for a quantitative study on the interaction of human proteins (albumin and fibrinogen) with the hydrogel by Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D). This technique enables the determination of adsorbant mass and changes in the shear modulus of the hydrogel layer upon adsorption of human proteins. Furthermore, Secondary Ion Mass Spectrometry and principal component analysis was applied to monitor the changed composition of the topmost adsorbate layer. This approach opens interesting perspectives for a sensitive screening of viscoelastic biomaterials that could be used for regenerative medicine.
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Affiliation(s)
- Sina M S Schönwälder
- Karlsruhe Institute of Technology (KIT), Institute of Functional Interfaces (IFG) , 76344 Eggenstein-Leopoldshafen, Germany
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Liang Y, Kiick KL. Multifunctional lipid-coated polymer nanogels crosslinked by photo-triggered Michael-type addition. Polym Chem 2014. [DOI: 10.1039/c3py01269g] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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19
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Tan A, Goh D, Farhatnia Y, G N, Lim J, Teoh SH, Rajadas J, Alavijeh MS, Seifalian AM. An anti-CD34 antibody-functionalized clinical-grade POSS-PCU nanocomposite polymer for cardiovascular stent coating applications: a preliminary assessment of endothelial progenitor cell capture and hemocompatibility. PLoS One 2013; 8:e77112. [PMID: 24116210 PMCID: PMC3793009 DOI: 10.1371/journal.pone.0077112] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 08/30/2013] [Indexed: 12/29/2022] Open
Abstract
In situ endothelialization of cardiovascular implants has emerged in recent years as an attractive means of targeting the persistent problems of thrombosis and intimal hyperplasia. This study aimed to investigate the efficacy of immobilizing anti-CD34 antibodies onto a POSS-PCU nanocomposite polymer surface to sequester endothelial progenitor cells (EPCs) from human blood, and to characterize the surface properties and hemocompatibility of this surface. Amine-functionalized fumed silica was used to covalently conjugate anti-CD34 to the polymer surface. Water contact angle, fluorescence microscopy, and scanning electron microscopy were used for surface characterization. Peripheral blood mononuclear cells (PBMCs) were seeded on modified and pristine POSS-PCU polymer films. After 7 days, adhered cells were immunostained for the expression of EPC and endothelial cell markers, and assessed for the formation of EPC colonies. Hemocompatibility was assessed by thromboelastography, and platelet activation and adhesion assays. The number of EPC colonies formed on anti-CD34-coated POSS-PCU surfaces was not significantly higher than that of POSS-PCU (5.0±1.0 vs. 1.7±0.6, p>0.05). However, antibody conjugation significantly improved hemocompatibility, as seen from the prolonged reaction and clotting times, decreased angle and maximum amplitude (p<0.05), as well as decreased platelet adhesion (76.8±7.8 vs. 8.4±0.7, p<0.05) and activation. Here, we demonstrate that POSS-PCU surface immobilized anti-CD34 antibodies selectively captured CD34+ cells from peripheral blood, although only a minority of these were EPCs. Nevertheless, antibody conjugation significantly improves the hemocompatibility of POSS-PCU, and should therefore continue to be explored in combination with other strategies to improve the specificity of EPC capture to promote in situ endothelialization.
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Affiliation(s)
- Aaron Tan
- Centre for Nanotechnology and Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, United Kingdom
- UCL Medical School, University College London, London, United Kingdom
| | - Debbie Goh
- Centre for Nanotechnology and Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, United Kingdom
- UCL Medical School, University College London, London, United Kingdom
| | - Yasmin Farhatnia
- Centre for Nanotechnology and Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, United Kingdom
| | - Natasha G
- Centre for Nanotechnology and Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, United Kingdom
- UCL Medical School, University College London, London, United Kingdom
| | - Jing Lim
- Division of Bioengineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Swee-Hin Teoh
- Division of Bioengineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Jayakumar Rajadas
- Biomaterials and Advanced Drug Delivery Laboratory, School of Medicine, Stanford University, Stanford, California, United States of America
| | | | - Alexander M. Seifalian
- Centre for Nanotechnology and Regenerative Medicine, UCL Division of Surgery & Interventional Science, University College London, London, United Kingdom
- Royal Free London NHS Foundation Trust, London, United Kingdom
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20
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Affiliation(s)
- Smriti Singh
- DWI an der RWTH Aachen e.V. Functional and Interactive Polymers and Institute for Technical and Macromolecular Chemistry, RWTH Aachen University; 52056 Aachen Germany
| | - Martin Möller
- DWI an der RWTH Aachen e.V. Functional and Interactive Polymers and Institute for Technical and Macromolecular Chemistry, RWTH Aachen University; 52056 Aachen Germany
| | - Andrij Pich
- DWI an der RWTH Aachen e.V. Functional and Interactive Polymers and Institute for Technical and Macromolecular Chemistry, RWTH Aachen University; 52056 Aachen Germany
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Multilayered textile coating based on a β-cyclodextrin polyelectrolyte for the controlled release of drugs. Carbohydr Polym 2013; 93:718-30. [DOI: 10.1016/j.carbpol.2012.12.055] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Revised: 12/14/2012] [Accepted: 12/19/2012] [Indexed: 12/30/2022]
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22
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Donahoe CD, Cohen TL, Li W, Nguyen PK, Fortner JD, Mitra RD, Elbert DL. Ultralow protein adsorbing coatings from clickable PEG nanogel solutions: benefits of attachment under salt-induced phase separation conditions and comparison with PEG/albumin nanogel coatings. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:4128-39. [PMID: 23441808 PMCID: PMC3618222 DOI: 10.1021/la3051115] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Clickable nanogel solutions were synthesized by using the copper catalyzed azide/alkyne cycloaddition (CuAAC) to partially polymerize solutions of azide and alkyne functionalized poly(ethylene glycol) (PEG) monomers. Coatings were fabricated using a second click reaction: a UV thiol-yne attachment of the nanogel solutions to mercaptosilanated glass. Because the CuAAC reaction was effectively halted by the addition of a copper-chelator, we were able to prevent bulk gelation and limit the coating thickness to a single monolayer of nanogels in the absence of the solution reaction. This enabled the inclusion of kosmotropic salts, which caused the PEG to phase-separate and nearly double the nanogel packing density, as confirmed by quartz crystal microbalance with dissipation (QCM-D). Protein adsorption was analyzed by single molecule counting with total internal reflection fluorescence (TIRF) microscopy and cell adhesion assays. Coatings formed from the phase-separated clickable nanogel solutions attached with salt adsorbed significantly less fibrinogen than other 100% PEG coatings tested, as well as poly(L-lysine)-g-PEG (PLL-g-PEG) coatings. However, PEG/albumin nanogel coatings still outperformed the best 100% PEG clickable nanogel coatings. Additional surface cross-linking of the clickable nanogel coating in the presence of copper further reduced levels of fibrinogen adsorption closer to those of PEG/albumin nanogel coatings. However, this step negatively impacted long-term resistance to cell adhesion and dramatically altered the morphology of the coating by atomic force microscopy (AFM). The main benefit of the click strategy is that the partially polymerized solutions are stable almost indefinitely, allowing attachment in the phase-separated state without danger of bulk gelation, and thus producing the best performing 100% PEG coating that we have studied to date.
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Affiliation(s)
- Casey D. Donahoe
- Department of Biomedical Engineering, Washington University in St. Louis, Campus Box 1097, 1 Brookings Drive, St. Louis, MO 63130, United States
| | - Thomas L. Cohen
- Department of Genetics, Washington University in St. Louis, Campus Box 8510, 4444 Forest Park Boulevard, St. Louis, MO 63108, United States
| | - Wenlu Li
- Department of Energy, Environmental, & Chemical Engineering, Washington University in St. Louis, 1 Brookings Drive, St. Louis, MO 63130, United States
| | - Peter K. Nguyen
- Department of Biomedical Engineering, Washington University in St. Louis, Campus Box 1097, 1 Brookings Drive, St. Louis, MO 63130, United States
| | - John D. Fortner
- Department of Energy, Environmental, & Chemical Engineering, Washington University in St. Louis, 1 Brookings Drive, St. Louis, MO 63130, United States
| | - Robi D. Mitra
- Department of Biomedical Engineering, Washington University in St. Louis, Campus Box 1097, 1 Brookings Drive, St. Louis, MO 63130, United States
- Department of Genetics, Washington University in St. Louis, Campus Box 8510, 4444 Forest Park Boulevard, St. Louis, MO 63108, United States
| | - Donald L. Elbert
- Department of Biomedical Engineering, Washington University in St. Louis, Campus Box 1097, 1 Brookings Drive, St. Louis, MO 63130, United States
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Leclercq L, Modena E, Vert M. Adsorption of proteins at physiological concentrations on pegylated surfaces and the compatibilizing role of adsorbed albumin with respect to other proteins according to optical waveguide lightmode spectroscopy (OWLS). JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2013; 24:1499-518. [DOI: 10.1080/09205063.2013.772045] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Laurent Leclercq
- a Faculty of Pharmacy, Max Mousseron Institute of Biomolecules , UMR CNRS 5247, University Montpellier 1, Team CRBA, 15 Avenue Charles Flahault, BP 14491, 34093, Montpellier Cedex 5 , France
| | - Enrico Modena
- a Faculty of Pharmacy, Max Mousseron Institute of Biomolecules , UMR CNRS 5247, University Montpellier 1, Team CRBA, 15 Avenue Charles Flahault, BP 14491, 34093, Montpellier Cedex 5 , France
| | - Michel Vert
- a Faculty of Pharmacy, Max Mousseron Institute of Biomolecules , UMR CNRS 5247, University Montpellier 1, Team CRBA, 15 Avenue Charles Flahault, BP 14491, 34093, Montpellier Cedex 5 , France
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Wang Y, Hong Q, Chen Y, Lian X, Xiong Y. Surface properties of polyurethanes modified by bioactive polysaccharide-based polyelectrolyte multilayers. Colloids Surf B Biointerfaces 2012; 100:77-83. [DOI: 10.1016/j.colsurfb.2012.05.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 05/22/2012] [Accepted: 05/28/2012] [Indexed: 10/28/2022]
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Bearat HH, Lee BH, Vernon BL. Comparison of properties between NIPAAm-based simultaneously physically and chemically gelling polymer systems for use in vivo. Acta Biomater 2012; 8:3629-42. [PMID: 22705635 DOI: 10.1016/j.actbio.2012.06.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 05/02/2012] [Accepted: 06/07/2012] [Indexed: 11/17/2022]
Abstract
In this work, a comparison between two different physical-chemical gels, poly(NIPAAm-co-cysteamine) with poly(NIPAAm-co-cysteamine-vinylsulfone) and poly(NIPAAm-co-cysteamine) with poly(NIPAAm-co-HEMA-acrylate), is made. These hydrogels undergo gelation via dual mechanisms: temperature sensitivity (physical gelation) and chemical crosslinking (chemical gelation). The advantages of using both gelation mechanisms are to reduce the creep experienced by purely physical gels and to increase the elastic modulus of purely chemical gels. Here, the physical-chemical gels were synthesized and characterized for their chemical, structural, thermal, mechanical and morphological properties. The gels were also tested for their gelation kinetics, swelling, degradation and cytotoxicity. The copolymers were successfully synthesized and their phase transition temperatures fall in a feasible range (29-34°C) for use in vivo. With rheology, it was shown that use of simultaneous physical and chemical gelation resulted in improved properties, with increased elastic moduli and reduced frequency dependence. The rates of reaction of thiols to vinyls differ between the two systems, demonstrating a greater effect of chemical gelation in one gelling system over the other, due to the faster rate of thiols consumed into reaction. The morphology of the gels proved to be quite different when analyzed by scanning electron microscopy, showing differences in swelling behaviors. Cell studies illustrated good growth of cells exposed to the gels. Both hydrogels, although possessing slight differences, demonstrate the capability of being injected in vivo for use as embolic agents for occlusion of aneurysms.
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Affiliation(s)
- Hanin H Bearat
- The School of Biological and Health Systems Engineering, Center for Interventional Biomaterials, ECG 334, Arizona State University, Tempe, AZ 85287-9709, USA
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Singh S, Blöhbaum J, Möller M, Pich A. Biohybrid nanogels by crosslinking of ovalbumin with reactive star-PEGs in W/O emulsions. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/pola.26236] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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27
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Tseng PY, Chang YC. Tethered fibronectin liposomes on supported lipid bilayers as a prepackaged controlled-release platform for cell-based assays. Biomacromolecules 2012; 13:2254-62. [PMID: 22721275 DOI: 10.1021/bm300426u] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A biomimetic construct containing an extracellular matrix protein-liposome composite tethered on supported lipid bilayers (SLBs) was formed with fibronectin (FN), and polyethylene glycol (PEG) and cholesterol-containing liposomes. The construct can serve as a multifunctional platform for cell attachment and drug release. The successful fabrication of the FN-liposome-SLB model platform was analyzed in situ with a quartz crystal microbalance with dissipation. The long-term stability of the surface tethered liposomes was measured via an encapsulated fluorescent probe. Less than 20% of the fluorescent probe content was released in 8 days, which compared favorably to the release of 90% of the probe content in one day from a similar construct made without PEG and cholesterol. HeLa cells were used to study the cellular interactions with the model platform. The extracellular matrix composition, FN, was found to be essential to promote HeLa cell adhesion on the liposome-SLB surfaces. Upon cell adhesion, the liposomes were spatially reorganized and absorbed by the cells. The rate of HeLa cell apoptosis was correlated with the surface density of doxorubicin-loaded liposomes, confirming the effective drug delivery through liposomes. The multifunctional model platform could be useful as preadministered, controlled-release platforms for cell- and tissue-based assays.
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Affiliation(s)
- Po-Yuan Tseng
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
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Guha S, Wayment JR, Li M, Tarlov MJ, Zachariah MR. Protein adsorption–desorption on electrospray capillary walls – No influence on aggregate distribution. J Colloid Interface Sci 2012; 377:476-84. [DOI: 10.1016/j.jcis.2012.03.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 03/19/2012] [Accepted: 03/20/2012] [Indexed: 02/02/2023]
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Protein deposition on contact lenses: The past, the present, and the future. Cont Lens Anterior Eye 2012; 35:53-64. [DOI: 10.1016/j.clae.2011.12.005] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2010] [Revised: 12/18/2011] [Accepted: 12/24/2011] [Indexed: 11/19/2022]
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Meyers SR, Grinstaff MW. Biocompatible and bioactive surface modifications for prolonged in vivo efficacy. Chem Rev 2012; 112:1615-32. [PMID: 22007787 PMCID: PMC3878818 DOI: 10.1021/cr2000916] [Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Steven R. Meyers
- Departments of Biomedical Engineering and Chemistry, Boston University, Boston, MA 02215, USA
| | - Mark W. Grinstaff
- Departments of Biomedical Engineering and Chemistry, Boston University, Boston, MA 02215, USA
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Gopishetty V, Tokarev I, Minko S. Biocompatible stimuli-responsive hydrogel porous membranes via phase separation of a polyvinyl alcohol and Na-alginate intermolecular complex. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm31778h] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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NCO-sP(EO-stat-PO) coatings on gold sensors--a QCM study of hemocompatibility. SENSORS 2011; 11:5253-69. [PMID: 22163899 PMCID: PMC3231391 DOI: 10.3390/s110505253] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 04/19/2011] [Accepted: 05/09/2011] [Indexed: 11/17/2022]
Abstract
The reliability of implantable blood sensors is often hampered by unspecific adsorption of plasma proteins and blood cells. This not only leads to a loss of sensor signal over time, but can also result in undesired host vs. graft reactions. Within this study we evaluated the hemocompatibility of isocyanate conjugated star shaped polytheylene oxide-polypropylene oxide co-polymers NCO-sP(EO-stat-PO) when applied to gold surfaces as an auspicious coating material for gold sputtered blood contacting sensors. Quartz crystal microbalance (QCM) sensors were coated with ultrathin NCO-sP(EO-stat-PO) films and compared with uncoated gold sensors. Protein resistance was assessed by QCM measurements with fibrinogen solution and platelet poor plasma (PPP), followed by quantification of fibrinogen adsorption. Hemocompatibility was tested by incubation with human platelet rich plasma (PRP). Thrombin antithrombin-III complex (TAT), β-thromboglobulin (β-TG) and platelet factor 4 (PF4) were used as coagulation activation markers. Furthermore, scanning electron microscopy (SEM) was used to visualize platelet adhesion to the sensor surfaces. Compared to uncoated gold sensors, NCO-sP(EO-stat-PO) coated sensors revealed significant better resistance against protein adsorption, lower TAT generation and a lower amount of adherent platelets. Moreover, coating with ultrathin NCO-sP(EO-stat-PO) films creates a cell resistant hemocompatible surface on gold that increases the chance of prolonged sensor functionality and can easily be modified with specific receptor molecules.
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In vivo PEG modification of vascular surfaces for targeted delivery. J Vasc Surg 2011; 55:1087-95. [PMID: 22169667 DOI: 10.1016/j.jvs.2011.09.081] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 09/23/2011] [Accepted: 09/24/2011] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Thrombosis and restenosis remain problematic for many intravascular procedures. Previously, it has been demonstrated that modifying an injured vascular surface with a protein-reactive polymer could block undesirable platelet deposition. As an added benefit, it would be advantageous if one could target therapeutics to the injured site. This study investigates a site-specific delivery system to target microspheres to vascular surfaces modified with a reactive polyethylene glycol tagged with biotin. METHODS Rabbit femoral arteries were injured with a 2F embolectomy catheter. Modification of the vascular surface was achieved using a channeled balloon catheter or small-diameter tube. Microspheres were injected intravenously through catheterization of the ear vein. Polymer modification on the injured surface and delivery of microspheres was quantified using epifluorescence microscopy at 0, 24, 48, and 72 hours. RESULTS Polymer modification of the vascular surface could be achieved using a channeled drug delivery catheter or small-diameter tube with similar results. Maximum polymer coverage occurred at 0 hours and decreased to 85% maximal at 24 hours, 72% at 48 hours, and 67% at 72 hours. The initial number of microspheres per mm(2) binding to modified, injured arteries was 304 versus 141 for the unmodified, damaged control (P < .01). At subsequent times, the number of adherent microspheres to modified, injured arteries decreased by 50%, 70%, and 84% at 24, 48, and 72 hours, respectively; while nonspecific binding to unmodified, injured arteries quickly decreased by 93%. Initial microsphere binding to modified, healthy arteries was 153 microspheres/mm(2) as opposed to 26 microspheres/mm(2) for the unmodified, healthy controls (P < .01). CONCLUSIONS Chemical modification of injured vessels following intravascular procedures can be readily accomplished in vivo to create a substrate for targeted delivery systems. As a proof of concept, targeted microspheres preferentially adhered to polymer-modified surfaces as opposed to injured, unmodified, or healthy vascular surfaces.
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Tessler LA, Mitra RD. Sensitive single-molecule protein quantification and protein complex detection in a microarray format. Proteomics 2011; 11:4731-5. [PMID: 22038904 DOI: 10.1002/pmic.201100361] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 10/03/2011] [Indexed: 01/21/2023]
Abstract
Single-molecule protein analysis provides sensitive protein quantitation with a digital read-out and is promising for studying biological systems and detecting biomarkers clinically. However, current single-molecule platforms rely on the quantification of one protein at a time. Conventional antibody microarrays are scalable to detect many proteins simultaneously, but they rely on less sensitive and less quantitative quantification by the ensemble averaging of fluorescent molecules. Here, we demonstrate a single-molecule protein assay in a microarray format enabled by an ultra-low background surface and single-molecule imaging. The digital read-out provides a highly sensitive, low femtomolar limit of detection and four orders of magnitude of dynamic range through the use of hybrid digital-analog quantification. From crude cell lysate, we measured levels of p53 and MDM2 in parallel, proving the concept of a digital antibody microarray for use in proteomic profiling. We also applied the single-molecule microarray to detect the p53-MDM2 protein complex in cell lysate. Our study is promising for development and application of single-molecule protein methods because it represents a technological bridge between single-plex and highly multiplex studies.
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Affiliation(s)
- Lee A Tessler
- Department of Genetics, Center for Genome Sciences and Systems Biology, Washington University, St. Louis, MO 63108, USA
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Chen N, Zhang Z, Soontornworajit B, Zhou J, Wang Y. Cell adhesion on an artificial extracellular matrix using aptamer-functionalized PEG hydrogels. Biomaterials 2011; 33:1353-62. [PMID: 22079002 DOI: 10.1016/j.biomaterials.2011.10.062] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2011] [Accepted: 10/22/2011] [Indexed: 01/12/2023]
Abstract
The development of an artificial extracellular matrix (ECM) is important to regenerative medicine because the ECM plays complex and dynamic roles in the regulation of cell behavior. In this study, nucleic acid aptamers were applied to functionalize hydrogels for mimicking the adhesion sites of the ECM. The results showed that nucleic acid aptamers could be incorporated into polyethylene glycol (PEG) hydrogels via free radical polymerization. The incorporation of the aptamers produced only a moderate effect on the mechanical properties of the PEG hydrogels. Importantly, the results also showed that the aptamers effectively induced cell type-specific adhesion to the PEG hydrogels without affecting cell viability. The cell adhesion was a function of the aptamer concentration, the spacer length and the cell seeding time. In addition, cell adhesion to the aptamer-functionalized hydrogel could be attenuated by means of aptamer inactivation in a physiological condition. Thus, aptamer-functionalized hydrogels are promising biomaterials for the development of artificial ECMs.
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Affiliation(s)
- Niancao Chen
- Program of Biomedical Engineering, School of Engineering, University of Connecticut, Storrs, CT 06269-3222, USA
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Mizrahi B, Irusta S, McKenna M, Stefanescu C, Yedidsion L, Myint M, Langer R, Kohane DS. Microgels for efficient protein purification. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:H258-H262. [PMID: 21805505 PMCID: PMC4157732 DOI: 10.1002/adma.201101258] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Indexed: 05/31/2023]
Affiliation(s)
- Boaz Mizrahi
- Children's Hospital Boston Division of Critical Care Medicine, Harvard Medical School, 300 Longwood Avenue. Bader 634 Boston, MA 02115, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Silvia Irusta
- Institute of Nanoscience of Aragón, University of Zaragoza, Mariano Esquillor s/n, Zaragoza, 50018, Spain
| | - Marshall McKenna
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Cristina Stefanescu
- Children's Hospital Boston Division of Critical Care Medicine, Harvard Medical School, 300 Longwood Avenue. Bader 634 Boston, MA 02115, USA
| | - Liron Yedidsion
- Operations Research Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - MyatNoeZin Myint
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Robert Langer
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Daniel S. Kohane
- Children's Hospital Boston Division of Critical Care Medicine, Harvard Medical School, 300 Longwood Avenue. Bader 634 Boston, MA 02115, USA
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Mahmud G, Huda S, Yang W, Kandere-Grzybowska K, Pilans D, Jiang S, Grzybowski BA. Carboxybetaine methacrylate polymers offer robust, long-term protection against cell adhesion. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:10800-4. [PMID: 21711048 PMCID: PMC3597224 DOI: 10.1021/la201066y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Films of poly(carboxybetaine methacrylate), poly(CBMA), grafted onto microetched gold slides are effective in preventing nonspecific adhesion of cells of different types. The degree of adhesion resistance is comparable to that achieved with the self-assembled monolayers, SAMs, of oligo(ethylene glycol) alkanethiolates. In sharp contrast to the SAMs, however, substrates protected with poly(CBMA) can be stored in dry state without losing their protective properties for periods up to 2 weeks.
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Affiliation(s)
- Goher Mahmud
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
| | - Sabil Huda
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
| | - Wei Yang
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195
| | - Kristiana Kandere-Grzybowska
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
| | - Didzis Pilans
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
| | - Shaoyi Jiang
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195
| | - Bartosz A. Grzybowski
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
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Vasdekis AE, Laporte GP. Enhancing single molecule imaging in optofluidics and microfluidics. Int J Mol Sci 2011; 12:5135-56. [PMID: 21954349 PMCID: PMC3179156 DOI: 10.3390/ijms12085135] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 05/23/2011] [Accepted: 07/25/2011] [Indexed: 12/25/2022] Open
Abstract
Microfluidics and optofluidics have revolutionized high-throughput analysis and chemical synthesis over the past decade. Single molecule imaging has witnessed similar growth, due to its capacity to reveal heterogeneities at high spatial and temporal resolutions. However, both resolution types are dependent on the signal to noise ratio (SNR) of the image. In this paper, we review how the SNR can be enhanced in optofluidics and microfluidics. Starting with optofluidics, we outline integrated photonic structures that increase the signal emitted by single chromophores and minimize the excitation volume. Turning then to microfluidics, we review the compatible functionalization strategies that reduce noise stemming from non-specific interactions and architectures that minimize bleaching and blinking.
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Affiliation(s)
- Andreas E. Vasdekis
- Optics Laboratory, School of Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland; E-Mail:
| | - Gregoire P.J. Laporte
- Optics Laboratory, School of Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland; E-Mail:
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Ravindran S, Roam JL, Nguyen PK, Hering TM, Elbert DL, McAlinden A. Changes of chondrocyte expression profiles in human MSC aggregates in the presence of PEG microspheres and TGF-β3. Biomaterials 2011; 32:8436-45. [PMID: 21820171 DOI: 10.1016/j.biomaterials.2011.07.056] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 07/17/2011] [Indexed: 11/27/2022]
Abstract
Biomaterial microparticles are commonly utilized as growth factor delivery vehicles to induce chondrogenic differentiation of mesenchymal stem/stromal cells (MSCs). To address whether the presence of microparticles could themselves affect differentiation of MSCs, a 3D co-aggregate system was developed containing an equal volume of human primary bone marrow-derived MSCs and non-degradable RGD-conjugated poly(ethylene glycol) microspheres (PEG-μs). Following TGF-β3 induction, differences in cell phenotype, gene expression and protein localization patterns were found when compared to MSC aggregate cultures devoid of PEG-μs. An outer fibrous layer always found in differentiated MSC aggregate cultures was not formed in the presence of PEG-μs. Type II collagen protein was synthesized by cells in both culture systems, although increased levels of the long (embryonic) procollagen isoforms were found in MSC/PEG-μs aggregates. Ubiquitous deposition of type I and type X collagen proteins was found in MSC/PEG-μs cultures while the expression patterns of these collagens was restricted to specific areas in MSC aggregates. These findings show that MSCs respond differently to TGF-β3 when in a PEG-μs environment due to effects of cell dilution, altered growth factor diffusion and/or cellular interactions with the microspheres. Although not all of the expression patterns pointed toward improved chondrogenic differentiation in the MSC/PEG-μs cultures, the surprisingly large impact of the microparticles themselves should be considered when designing drug delivery/scaffold strategies.
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Affiliation(s)
- Soumya Ravindran
- Department of Orthopaedic Surgery, Washington University School of Medicine, 660 South Euclid Avenue, St Louis, MO 63110, USA
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Contreras AE, Steiner Z, Miao J, Kasher R, Li Q. Studying the role of common membrane surface functionalities on adsorption and cleaning of organic foulants using QCM-D. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:6309-6315. [PMID: 21728383 DOI: 10.1021/es200570t] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Adsorption of organic foulants on nanofiltration (NF) and reverse osmosis (RO) membrane surfaces strongly affects subsequent fouling behavior by modifying the membrane surface. In this study, impact on organic foulant adsorption of specific chemistries including those in commercial thin-film composite membranes was investigated using self-assembled monolayers with seven different ending chemical functionalities (-CH(3), -O-phenyl, -NH(2), ethylene-glycol, -COOH, -CONH(2), and -OH). Adsorption and cleaning of protein (bovine serum albumin) and polysaccharide (sodium alginate) model foulants in two solution conditions were measured using quartz crystal microbalance with dissipation monitoring, and were found to strongly depend on surface functionality. Alginate adsorption correlated with surface hydrophobicity as measured by water contact angle in air; however, adsorption of BSA on hydrophilic -COOH, -NH(2), and -CONH(2) surfaces was high and dominated by hydrogen bond formation and electrostatic attraction. Adsorption of both BSA and alginate was the fastest on -COOH, and adsorption on -NH(2) and -CONH(2) was difficult to remove by surfactant cleaning. BSA adsorption kinetics was shown to be markedly faster than that of alginate, suggesting its importance in the formation of the conditioning layer. Surface modification to render -OH or ethylene-glycol functionalities are expected to reduce membrane fouling.
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Affiliation(s)
- Alison E Contreras
- Department of Civil and Environmental Engineering, Rice University, Houston Texas 77005, United States
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Dykstra PH, Roy V, Byrd C, Bentley WE, Ghodssi R. Microfluidic electrochemical sensor array for characterizing protein interactions with various functionalized surfaces. Anal Chem 2011; 83:5920-7. [PMID: 21688780 DOI: 10.1021/ac200835s] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a unique microfluidic platform to allow for quick and sensitive probing of protein adsorption to various functionalized surfaces. The ability to tailor a sensor surface for a specific analyte is crucial for the successful application of portable gas and fluid sensors and is of great interest to the drug screening community. However, choosing the correct surface chemistry to successfully passivate against nonspecific binding typically requires repeated trial and error experiments. The presented device incorporates an array of integrated electrochemical sensors for fast, sensitive, label-free detection of these binding interactions. The layout of the electrodes allows for loading various surface chemistries in one direction while sensing their interactions with particular compounds in another without any cross-contamination. Impedance data is collected for three commonly used passivation compounds (mercaptohexanol, polyethylene glycol, and bovine serum albumin) and demonstrates their interaction with three commonly studied proteins in genetic and cancer research (cAMP receptor protein, tumor necrosis factor α, and tumor necrosis factor β). The ability to quickly characterize various surface interactions provides knowledge for selecting optimal functionalization for any biosensor.
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Affiliation(s)
- Peter H Dykstra
- MEMS Sensors and Actuators Laboratory (MSAL), Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland, United States.
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Ignacio C, Barcellos L, Ferreira MD, Moura SAL, Soares IA, Oréfice RL. In vivo tests of a novel wound dressing based on biomaterials with tissue adhesion controlled through external stimuli. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:1357-1364. [PMID: 21437637 DOI: 10.1007/s10856-011-4299-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Accepted: 03/16/2011] [Indexed: 05/30/2023]
Abstract
The high incidence of wounds by second intention and the high costs associated with their treatment give rise to the need for the development of wound dressings that protect not only the wounds themselves but that are also able to promote cell proliferation and skin regeneration. Moreover, it is also very important that no damage to the new regenerated tissue is generated while removing the dressing. In this work, a novel wound dressing, which would be able to favor tissue repair and be removed at an appropriate scheduled moment by means of an external stimulus without promoting extensive damage to the new tissue, was produced and tested. Polyurethane membranes were modified by grafting polymers based on poly(n-isopropylacrylamide) (P-N-IPAAm). P-N-IPAAm undergoes a phase transition at approximately 32°C, which changes its behavior from hydrophilic (below 32°C) to hydrophobic. It was hypothesized that, by reducing the temperature near the wound dressing to values lower than 32°C, the detachment of the dressing would become more effective. The wound dressings containing P-N-IPAAm grafts were tested in vivo by covering excisional wounds produced in mice. The produced dressings were placed in direct contact with the lesions for 3 days. Results showed that the hypothermia due to anesthesia required to remove the dressings from mice lowered the local temperature to 28°C and favored the detachment of the wound dressings containing P-N-IPAAm grafts. Histological analyses showed that lesions covered by dressings presented less intense inflammatory events and denser connective tissue than did the wounds without dressings. The wounds covered by polyurethane membranes with P-N-IPAAm grafts showed signs of more intense re-epithelization and angiogenesis than did the lesions covered by polyurethane without grafts.
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Affiliation(s)
- C Ignacio
- Universidade Federal dos Vales do Jequitinhonha e Mucuri-UFVJM, Diamantina, MG, Brazil.
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Tessler LA, Donahoe CD, Garcia DJ, Jun YS, Elbert DL, Mitra RD. Nanogel surface coatings for improved single-molecule imaging substrates. J R Soc Interface 2011; 8:1400-8. [PMID: 21325313 DOI: 10.1098/rsif.2010.0669] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Surfaces that resist protein adsorption are important for many bioanalytical applications. Bovine serum albumin (BSA) coatings and multi-arm poly(ethylene glycol) (PEG) coatings display low levels of non-specific protein adsorption and have enabled highly quantitative single-molecule (SM) protein studies. Recently, a method was developed for coating a glass with PEG-BSA nanogels, a promising hybrid of these two low-background coatings. We characterized the nanogel coating to determine its suitability for SM protein experiments. SM adsorption counting revealed that nanogel-coated surfaces exhibit lower protein adsorption than covalently coupled BSA surfaces and monolayers of multi-arm PEG, so this surface displays one of the lowest degrees of protein adsorption yet observed. Additionally, the nanogel coating was resistant to DNA adsorption, underscoring the utility of the coating across a variety of SM experiments. The nanogel coating was found to be compatible with surfactants, whereas the BSA coating was not. Finally, applying the coating to a real-world study, we found that single ligand molecules could be tethered to this surface and detected with high sensitivity and specificity by a digital immunoassay. These results suggest that PEG-BSA nanogel coatings will be highly useful for the SM analysis of proteins.
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Affiliation(s)
- Lee A Tessler
- Department of Genetics and Center for Genome Sciences, Washington University School of Medicine, 4444 Forest Park Parkway, Campus Box 8510, St. Louis, MO 63108, USA
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Khoo X, O'Toole GA, Nair SA, Snyder BD, Kenan DJ, Grinstaff MW. Staphylococcus aureus resistance on titanium coated with multivalent PEGylated-peptides. Biomaterials 2010; 31:9285-92. [PMID: 20863561 DOI: 10.1016/j.biomaterials.2010.08.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 08/16/2010] [Indexed: 11/30/2022]
Abstract
Bacterial infections can have adverse effects on the efficacy, lifetime and safety of an implanted device and are the second most commonly attributed cause of orthopedic implant failure. We have previously shown the assembly of PEGylated titanium-binding peptides (TBPs) on Ti to obtain a bacteriophobic surface coating that can effectively resist protein adsorption and Staphylococcus aureus (S. aureus) adhesion. In the present study, we examine the effect of multiple TBP repeats on coating performance in vitro. Mono, di, and tetravalent peptides were synthesized and assessed for binding affinity and serum stability. PEGylated analogs were prepared and evaluated for their effect on S. aureus attachment and biofilm formation. Coating performance improved with the number of TBP repeats, with the tetravalent coating, TBP(4)-PEG, showing the best performance in all assays. In particular, TBP(4)-PEG forms a serum-resistant surface coating capable of preventing S. aureus colonization and subsequent biofilm formation. These results further support the role that multivalency can play in the development of improved surface coatings with enhanced stabilities and efficacy for in vivo clinical use.
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Affiliation(s)
- Xiaojuan Khoo
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
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Surface modification on polyurethanes by using bioactive carboxymethylated fungal glucan from Poria cocos. Colloids Surf B Biointerfaces 2010; 81:629-33. [PMID: 20817490 DOI: 10.1016/j.colsurfb.2010.08.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2010] [Revised: 07/19/2010] [Accepted: 08/06/2010] [Indexed: 11/21/2022]
Abstract
In this work, a water-insoluble β-D-glucan (PCSG), isolated from Poria cocos, was carboxymethylated to create a water-soluble derivative named as CP. After free amino groups have been introduced, CP was covalently immobilized onto PU surface. The hydrophilicity and the concentration of carboxyl group on the modified PU surface were determined. The fibrinogen and albumin adsorption to the surface, in vitro blood compatibility, and antibacterial activity of the surface against Pseudomonas aeruginosa were evaluated. The water contact angle measurement indicated that the hydrophilicity of PU surface increased after modification. The fibrinogen adsorption of the modified PU surface decreased 51.5%, compared with control PU. CP immobilization could prolong the blood coagulation time was suggested by APTT experiment. Antibacterial activity experiments indicated that CP modified surface obviously suppressed the growth of P. aeruginosa. Thereby, CP immobilization improves blood compatibility of PU surface and introduces special antibacterial bioactivity.
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Anand G, Jamadagni SN, Garde S, Belfort G. Self-assembly of TMAO at hydrophobic interfaces and its effect on protein adsorption: insights from experiments and simulations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:9695-9702. [PMID: 20334401 DOI: 10.1021/la100363m] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We offer a novel process to render hydrophobic surfaces resistant to relatively small proteins during adsorption. This was accomplished by self-assembly of a well-known natural osmolyte, trimethylamine oxide (TMAO), a small amphiphilic molecule, on a hydrophobic alkanethiol surface. Measurements of lysozyme (LYS) adsorption on several homogeneous substrates formed from functionalized alkanethiol self-assembled monolayers (SAMs) in the presence and absence of TMAO, and direct interaction energy between the protein and functionalized surfaces, demonstrate the protein-resistant properties of a noncovalently adsorbed self-assembled TMAO layer. Molecular dynamics simulations clearly show that TMAO molecules concentrate near the CH(3)-SAM surface and are preferentially excluded from LYS. Interestingly, TMAO molecules adsorb strongly on a hydrophobic CH(3)-SAM surface, but a trade-off between hydrogen bonding with water, and hydrophobic interactions with the underlying substrate results in a nonintuitive orientation of TMAO molecules at the interface. Additionally, hydrophobic interactions, usually responsible for nonspecific adsorption of proteins, are weakly affected by TMAO. In addition to TMAO, other osmolytes (sucrose, taurine, and betaine) and a larger homologue of TMAO (N,N-dimethylheptylamine-N-oxide) were tested for protein resistance and only N,N-dimethylheptylamine-N-oxide exhibited resistance similar to TMAO. The principle of osmolyte exclusion from the protein backbone is responsible for the protein-resistant property of the surface. We speculate that this novel process of surface modification may have wide applications due to its simplicity, low cost, regenerability, and flexibility.
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Affiliation(s)
- Gaurav Anand
- The Howard P. Isermann Department of Chemical Biological Engineering, and The Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
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Truong MY, Dutta NK, Choudhury NR, Kim M, Elvin CM, Hill AJ, Thierry B, Vasilev K. A pH-responsive interface derived from resilin-mimetic protein Rec1-resilin. Biomaterials 2010; 31:4434-46. [DOI: 10.1016/j.biomaterials.2010.02.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Accepted: 02/08/2010] [Indexed: 10/19/2022]
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Nezu T, Taira M, Saitoh S, Sasaki K, Araki Y. Viscoelastic adlayers of collagen and lysozyme studied using quartz crystal microbalance with dissipation monitoring. Int J Biol Macromol 2010; 46:396-403. [DOI: 10.1016/j.ijbiomac.2010.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 02/03/2010] [Accepted: 02/03/2010] [Indexed: 11/29/2022]
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