151
|
Onyskiw PJ, Eniola-Adefeso O. Effect of PEGylation on ligand-based targeting of drug carriers to the vascular wall in blood flow. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:11127-34. [PMID: 23919766 DOI: 10.1021/la402182j] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The blood vessel wall plays a prominent role in the development of many life-threatening diseases and as such is an attractive target for treatment. To target diseased tissue, particulate drug carriers often have their surfaces modified with antibodies or epitopes specific to vascular wall-expressed molecules, along with poly(ethylene glycol) (PEG) to improve carrier blood circulation time. However, little is known about the effect of poly(ethylene glycol) on carrier adhesion dynamics-specifically in blood flow. Here we examine the influence of different molecular weight PEG spacers on particle adhesion in blood flow. Anti-ICAM-1 or Sialyl Lewis(a) were grafted onto polystyrene 2 μm and 500 nm spheres via PEG spacers and perfused in blood over activated endothelial cells at physiological shear conditions. PEG spacers were shown to improve, reduce, or have no effect on the binding density of targeted-carriers depending on the PEG surface conformation, shear rate, and targeting moiety.
Collapse
Affiliation(s)
- Peter J Onyskiw
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | | |
Collapse
|
152
|
Sai H, Tan KW, Hur K, Asenath-Smith E, Hovden R, Jiang Y, Riccio M, Muller DA, Elser V, Estroff LA, Gruner SM, Wiesner U. Hierarchical Porous Polymer Scaffolds from Block Copolymers. Science 2013; 341:530-4. [DOI: 10.1126/science.1238159] [Citation(s) in RCA: 221] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
|
153
|
Browning MB, Russell B, Rivera J, Höök M, Cosgriff-Hernandez EM. Bioactive hydrogels with enhanced initial and sustained cell interactions. Biomacromolecules 2013; 14:2225-33. [PMID: 23758437 PMCID: PMC3749781 DOI: 10.1021/bm400634j] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The highly tunable properties of poly(ethylene glycol) (PEG)-based hydrogel systems permit their use in a wide array of regenerative medicine and drug delivery applications. One of the most valuable properties of PEG hydrogels is their intrinsic resistance to protein adsorption and cell adhesion, as it allows for a controlled introduction of desired bioactive factors including proteins, peptides, and drugs. Acrylate-PEG-N-hydroxysuccinimide (Acr-PEG-NHS) is widely utilized as a PEG linker to functionalize bioactive factors with photo-cross-linkable groups. This enables their facile incorporation into PEG hydrogel networks or the use of PEGylation strategies for drug delivery. However, PEG linkers can sterically block integrin binding sites on functionalized proteins and reduce cell-material interactions. In this study we demonstrate that reducing the density of PEG linkers on protein backbones during functionalization results in significantly improved cell adhesion and spreading to bioactive hydrogels. However, this reduction in functionalization density also increases protein loss from the matrix over time due to ester hydrolysis of the Acr-PEG-NHS linkers. To address this, a novel PEG linker, acrylamide-PEG-isocyanate (Aam-PEG-I), with enhanced hydrolytic stability was synthesized. It was found that decreasing functionalization density with Aam-PEG-I resulted in comparable increases in cell adhesion and spreading to Acr-PEG-NHS systems while maintaining protein and bioactivity levels within the hydrogel network over a significantly longer time frame. Thus, Aam-PEG-I provides a new option for protein functionalization for use in a wide range of applications that improves initial and sustained cell-material interactions to enhance control of bioactivity.
Collapse
Affiliation(s)
- Mary Beth Browning
- Department of Biomedical Engineering, Texas A&M University, 5045 Emerging Technologies Building, College Station, TX 77843-3120
| | - Brooke Russell
- Institute of Biosciences and Technology, Texas A&M University System Health Science Center, 2121 West Holcombe Boulevard, Houston, Texas 77303-3303
| | - Jose Rivera
- Institute of Biosciences and Technology, Texas A&M University System Health Science Center, 2121 West Holcombe Boulevard, Houston, Texas 77303-3303
| | - Magnus Höök
- Institute of Biosciences and Technology, Texas A&M University System Health Science Center, 2121 West Holcombe Boulevard, Houston, Texas 77303-3303
| | - Elizabeth M. Cosgriff-Hernandez
- Institute of Biosciences and Technology, Texas A&M University System Health Science Center, 2121 West Holcombe Boulevard, Houston, Texas 77303-3303
| |
Collapse
|
154
|
Direct grafting of anti-fouling polyglycerol layers to steel and other technically relevant materials. Colloids Surf B Biointerfaces 2013; 111:360-6. [PMID: 23856542 DOI: 10.1016/j.colsurfb.2013.05.026] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Revised: 05/14/2013] [Accepted: 05/17/2013] [Indexed: 12/29/2022]
Abstract
Direct grafting of hyperbranched polyglycerol (PG) layers onto the oxide surfaces of steel, aluminum, and silicon has been achieved through surface-initiated polymerization of 2-hydroxymethyloxirane (glycidol). Optimization of the deposition conditions led to a protocol that employed N-methyl-2-pyrrolidone (NMP) as the solvent and temperatures of 100 and 140 °C, depending on the substrate material. In all cases, a linear growth of the PG layers could be attained, which allows for control of film thickness by altering the reaction time. At layer thicknesses >5 nm, the PG layers completely suppressed the adhesion of albumin, fibrinogen, and globulin. These layers were also at least 90% bio-repulsive for two bacteria strains, E. coli and Acinetobacter baylyi, with further improvement being observed when the PG film thickness was increased to 17 nm (up to 99.9% bio-repulsivity on silicon).
Collapse
|
155
|
Buitinga M, Truckenmüller R, Engelse MA, Moroni L, Ten Hoopen HWM, van Blitterswijk CA, de Koning EJP, van Apeldoorn AA, Karperien M. Microwell scaffolds for the extrahepatic transplantation of islets of Langerhans. PLoS One 2013; 8:e64772. [PMID: 23737999 PMCID: PMC3667808 DOI: 10.1371/journal.pone.0064772] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Accepted: 04/17/2013] [Indexed: 11/30/2022] Open
Abstract
Allogeneic islet transplantation into the liver has the potential to restore normoglycemia in patients with type 1 diabetes. However, the suboptimal microenvironment for islets in the liver is likely to be involved in the progressive islet dysfunction that is often observed post-transplantation. This study validates a novel microwell scaffold platform to be used for the extrahepatic transplantation of islet of Langerhans. Scaffolds were fabricated from either a thin polymer film or an electrospun mesh of poly(ethylene oxide terephthalate)-poly(butylene terephthalate) (PEOT/PBT) block copolymer (composition: 4000PEOT30PBT70) and were imprinted with microwells, ∼400 µm in diameter and ∼350 µm in depth. The water contact angle and water uptake were 39±2° and 52.1±4.0 wt%, respectively. The glucose flux through electrospun scaffolds was three times higher than for thin film scaffolds, indicating enhanced nutrient diffusion. Human islets cultured in microwell scaffolds for seven days showed insulin release and insulin content comparable to those of free-floating control islets. Islet morphology and insulin and glucagon expression were maintained during culture in the microwell scaffolds. Our results indicate that the microwell scaffold platform prevents islet aggregation by confinement of individual islets in separate microwells, preserves the islet’s native rounded morphology, and provides a protective environment without impairing islet functionality, making it a promising platform for use in extrahepatic islet transplantation.
Collapse
Affiliation(s)
- Mijke Buitinga
- Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Roman Truckenmüller
- Department of Tissue Regeneration, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Marten A. Engelse
- Department of Nephrology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Lorenzo Moroni
- Department of Tissue Regeneration, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Hetty W. M. Ten Hoopen
- Department of BioMedical Chemisty, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | | | - Eelco JP. de Koning
- Department of Nephrology, Leiden University Medical Centre, Leiden, The Netherlands
- Department of Endocrinology, Leiden University Medical Centre, Leiden, The Netherlands
- Hubrecht Institute–Royal Netherlands Academy of Arts and Sciences (KNAW) and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Aart A. van Apeldoorn
- Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
- * E-mail:
| | - Marcel Karperien
- Department of Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| |
Collapse
|
156
|
Page JM, Harmata AJ, Guelcher SA. Design and development of reactive injectable and settable polymeric biomaterials. J Biomed Mater Res A 2013; 101:3630-45. [DOI: 10.1002/jbm.a.34665] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 02/05/2013] [Accepted: 02/14/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Jonathan M. Page
- Department of Chemical and Biomolecular Engineering; Vanderbilt University; Nashville Tennessee
- Center for Bone Biology; Department of Medicine; Vanderbilt University Medical Center; Nashville Tennessee
| | - Andrew J. Harmata
- Department of Chemical and Biomolecular Engineering; Vanderbilt University; Nashville Tennessee
- Center for Bone Biology; Department of Medicine; Vanderbilt University Medical Center; Nashville Tennessee
| | - Scott A. Guelcher
- Department of Chemical and Biomolecular Engineering; Vanderbilt University; Nashville Tennessee
- Center for Bone Biology; Department of Medicine; Vanderbilt University Medical Center; Nashville Tennessee
- Department of Biomedical Engineering; Vanderbilt University; Nashville Tennessee
| |
Collapse
|
157
|
Yañez-Soto B, Liliensiek S, Murphy CJ, Nealey PF. Biochemically and topographically engineered poly(ethylene glycol) diacrylate hydrogels with biomimetic characteristics as substrates for human corneal epithelial cells. J Biomed Mater Res A 2013; 101:1184-94. [PMID: 23255502 PMCID: PMC3581740 DOI: 10.1002/jbm.a.34412] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 06/18/2012] [Accepted: 08/06/2012] [Indexed: 11/11/2022]
Abstract
Incorporation of biophysical and biochemical cues into the design of biomaterials is an important strategy for tissue engineering, the design of biomedical implants and cell culture. Hydrogels synthesized from poly(ethylene glycol) diacrylate (PEGDA) were investigated as a platform to simultaneously present human corneal epithelial cells (HCECs) in vitro with topography and adhesion peptides to mimic the native physical and chemical attributes of the basement membrane underlying the epithelium in vivo. Hydrogels synthesized from aqueous solutions of 20% PEGDA (M(w) = 3400 g/mol) prevented nonspecific cell adhesion and were functionalized with the integrin-binding peptide Arg-Gly-Asp (RGD) in concentrations from 5 to 20 mM. The hydrogels swelled minimally after curing and were molded with ridge and groove features with lateral dimensions from 200 to 2000 nm and 300-nm depth. HCECs were cultured on topographic surfaces functionalized with RGD and compared with control unfunctionalized topographic substrates. HCEC alignment, either parallel or perpendicular to ridges, was influenced by the culture media on substrates promoting nonspecific attachment. In contrast, the alignment of HCECs cultured on RGD hydrogels showed substantially less dependence on the culture media. In the latter case, the moldable RGD-functionalized hydrogels allowed for decoupling the cues from surface chemistry, soluble factors, and topography that simultaneously impact HCEC behavior.
Collapse
Affiliation(s)
- B. Yañez-Soto
- Department of Chemical and Biological Engineering, School of Engineering, University of Wisconsin, Madison, 53706, WI, USA
| | - S.J. Liliensiek
- Department of Chemical and Biological Engineering, School of Engineering, University of Wisconsin, Madison, 53706, WI, USA
| | - C. J. Murphy
- Department of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, Davis, CA, 95616, USA
- Department of Ophthalmology and Vision Sciences, School of Medicine, University of California, Davis, Davis, CA, 95817, USA
| | - P. F. Nealey
- Department of Chemical and Biological Engineering, School of Engineering, University of Wisconsin, Madison, 53706, WI, USA
| |
Collapse
|
158
|
Salmaso S, Caliceti P. Stealth properties to improve therapeutic efficacy of drug nanocarriers. JOURNAL OF DRUG DELIVERY 2013; 2013:374252. [PMID: 23533769 PMCID: PMC3606770 DOI: 10.1155/2013/374252] [Citation(s) in RCA: 194] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Accepted: 02/06/2013] [Indexed: 12/23/2022]
Abstract
Over the last few decades, nanocarriers for drug delivery have emerged as powerful tools with unquestionable potential to improve the therapeutic efficacy of anticancer drugs. Many colloidal drug delivery systems are underdevelopment to ameliorate the site specificity of drug action and reduce the systemic side effects. By virtue of their small size they can be injected intravenously and disposed into the target tissues where they release the drug. Nanocarriers interact massively with the surrounding environment, namely, endothelium vessels as well as cells and blood proteins. Consequently, they are rapidly removed from the circulation mostly by the mononuclear phagocyte system. In order to endow nanosystems with long circulation properties, new technologies aimed at the surface modification of their physicochemical features have been developed. In particular, stealth nanocarriers can be obtained by polymeric coating. In this paper, the basic concept underlining the "stealth" properties of drug nanocarriers, the parameters influencing the polymer coating performance in terms of opsonins/macrophages interaction with the colloid surface, the most commonly used materials for the coating process and the outcomes of this peculiar procedure are thoroughly discussed.
Collapse
Affiliation(s)
- Stefano Salmaso
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via F. Marzolo 5, 35131 Padova, Italy
| | - Paolo Caliceti
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via F. Marzolo 5, 35131 Padova, Italy
| |
Collapse
|
159
|
Podila R, Moore T, Alexis F, Rao A. Graphene coatings for biomedical implants. J Vis Exp 2013:e50276. [PMID: 23486380 DOI: 10.3791/50276] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Atomically smooth graphene as a surface coating has potential to improve implant properties. This demonstrates a method for coating nitinol alloys with nanometer thick layers of graphene for applications as a stent material. Graphene was grown on copper substrates via chemical vapor deposition and then transferred onto nitinol substrates. In order to understand how the graphene coating could change biological response, cell viability of rat aortic endothelial cells and rat aortic smooth muscle cells was investigated. Moreover, the effect of graphene-coatings on cell adhesion and morphology was examined with fluorescent confocal microscopy. Cells were stained for actin and nuclei, and there were noticeable differences between pristine nitinol samples compared to graphene-coated samples. Total actin expression from rat aortic smooth muscle cells was found using western blot. Protein adsorption characteristics, an indicator for potential thrombogenicity, were determined for serum albumin and fibrinogen with gel electrophoresis. Moreover, the transfer of charge from fibrinogen to substrate was deduced using Raman spectroscopy. It was found that graphene coating on nitinol substrates met the functional requirements for a stent material and improved the biological response compared to uncoated nitinol. Thus, graphene-coated nitinol is a viable candidate for a stent material.
Collapse
|
160
|
Kirschner CM, Anseth KS. Hydrogels in Healthcare: From Static to Dynamic Material Microenvironments. ACTA MATERIALIA 2013; 61:931-944. [PMID: 23929381 PMCID: PMC3735227 DOI: 10.1016/j.actamat.2012.10.037] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Advances in hydrogel design have revolutionized the way biomaterials are applied to address biomedical needs. Hydrogels were introduced in medicine over 50 years ago and have evolved from static, bioinert materials to dynamic, bioactive microenvironments, which can be used to direct specific biological responses such as cellular ingrowth in wound healing or on-demand delivery of therapeutics. Two general classes of mechanisms, those defined by the user and those dictated by the endogenous cells and tissues, can control dynamic hydrogel microenvironments. These highly tunable materials have provided bioengineers and biological scientists with new ways to not only treat patients in the clinic but to study the fundamental cellular responses to engineered microenvironments as well. Here, we provide a brief history of hydrogels in medicine and follow with a discussion of the synthesis and implementation of dynamic hydrogel microenvironments for healthcare-related applications.
Collapse
Affiliation(s)
- Chelsea M. Kirschner
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado, USA
| | - Kristi S. Anseth
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado, USA
- Biofrontiers Institute, University of Colorado, Boulder, Colorado, USA
- Howard Hughes Medical Institute, University of Colorado, Boulder, Colorado, USA
| |
Collapse
|
161
|
Hlídková H, Horák D, Proks V, Kučerová Z, Pekárek M, Kučka J. PEG-Modified Macroporous Poly(Glycidyl Methacrylate) and Poly(2-Hydroxyethyl Methacrylate) Microspheres to Reduce Non-Specific Protein Adsorption. Macromol Biosci 2013; 13:503-11. [DOI: 10.1002/mabi.201200446] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Indexed: 11/05/2022]
|
162
|
Abstract
We report that proteins labeled with fluorescein-doped silica nanoparticles (FSNPs) showed drastically different fouling behavior than those labeled with the fluorescein dye. Arrays of polymer films were covalently immobilized on silicon wafers and were treated with protein conjugated on FSNPs. Fluorescence imaging showed that the protein-FSNP conjugate adsorbed strongly on hydrophilic polymers such as poly(ethylene oxide) (PEO) and weakly on hydrophobic polymers such as polystyrene (PS), and the extent of adsorption decreased with increasing hydrophobicity of the polymer film. Thus, carbohydrate microarrays probed with FSNP-labeled lectin showed significantly enhanced signals when PS was used as the antifouling coating than when PEO was used, or when using bovine serum albumin as the blocking agent.
Collapse
Affiliation(s)
- Hui Wang
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA 01854
| | - Qi Tong
- Department of Chemistry, Portland State University, Portland, OR 97207
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA 01854
| |
Collapse
|
163
|
Horinouchi A, Tanaka K. An effect of stereoregularity on the structure of poly(methyl methacrylate) at air and water interfaces. RSC Adv 2013. [DOI: 10.1039/c3ra40631h] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
164
|
Gong YH, Yang J, Cao FY, Zhang J, Cheng H, Zhuo RX, Zhang XZ. Photoresponsive smart template for reversible cell micropatterning. J Mater Chem B 2013; 1:2013-2017. [DOI: 10.1039/c3tb20073f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
165
|
Boardman AK, Allison S, Sharon A, Sauer-Budge AF. Comparison of anti-fouling surface coatings for applications in bacteremia diagnostics. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2013; 5:273-280. [PMID: 25147402 PMCID: PMC4137785 DOI: 10.1039/c2ay25662b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To accurately diagnose microbial infections in blood, it is essential to recover as many microorganisms from a sample as possible. Unfortunately, recovering such microorganisms depends significantly on their adhesion to the surfaces of diagnostic devices. Consequently, we sought to minimize the adhesion of methicillin-sensitive Staphylococcus aureus (MSSA) to the surface of polypropylene- and acrylic-based bacteria concentration devices. These devices were treated with 11 different coatings having various charges and hydrophobicities. Some coatings promoted bacterial adhesion under centrifugation, whereas others were more likely to prevent it. Experiments were run using a simple buffer system and lysed blood, both inoculated with MSSA. Under both conditions, Hydromer's 7-TS-13 and Aqua65JL were most effective at reducing bacterial adhesion.
Collapse
Affiliation(s)
- Anna K. Boardman
- Center for Manufacturing Innovation, Fraunhofer USA, Brookline, MA 02446, USA
| | - Sandra Allison
- Center for Manufacturing Innovation, Fraunhofer USA, Brookline, MA 02446, USA
| | - Andre Sharon
- Center for Manufacturing Innovation, Fraunhofer USA, Brookline, MA 02446, USA
- Department of Mechanical Engineering, Boston University, Boston, MA 02215, USA
| | - Alexis F. Sauer-Budge
- Center for Manufacturing Innovation, Fraunhofer USA, Brookline, MA 02446, USA
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| |
Collapse
|
166
|
|
167
|
Kim HS, Ham HO, Son YJ, Messersmith PB, Yoo HS. Electrospun catechol-modified poly(ethyleneglycol) nanofibrous mesh for anti-fouling properties. J Mater Chem B 2013; 1:3940-3949. [DOI: 10.1039/c3tb20444h] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
168
|
Podila R, Moore T, Alexis F, Rao AM. Graphene coatings for enhanced hemo-compatibility of nitinol stents. RSC Adv 2013. [DOI: 10.1039/c2ra23073a] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
169
|
Feng Y, Zhao H, Behl M, Lendlein A, Guo J, Yang D. Grafting of poly(ethylene glycol) monoacrylates on polycarbonateurethane by UV initiated polymerization for improving hemocompatibility. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2013; 24:61-70. [PMID: 22661245 DOI: 10.1007/s10856-012-4685-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 05/16/2012] [Indexed: 06/01/2023]
Abstract
Poly(ethylene glycol) monoacrylates (PEGMAs) with a molecular weight between 400 and 1,000 g mol(-1) were grafted by ultraviolet initiated photopolymerization on the surface of polycarbonateurethane (PCU) for increasing its hydrophilicity and improving its hemocompatibility. The surface-grafted PCU films were characterized by Fourier transformation infrared spectroscopy, X-ray photoelectron spectroscopy, water contact angle, scanning electron microscopy (SEM) and atomic force microscopy measurements. The surface properties of the modified films were studied in dry and wetted state. Blood compatibility of the surfaces was evaluated by platelet adhesion tests and adhered platelets were determined by SEM. The results showed that the hydrophilicity of the films had been increased significantly by grafting PEGMAs, and platelets adhesion onto the film surface was obviously suppressed. Furthermore, the molecular weight of PEGMAs had a great effect on the hydrophilicity and hemocompatibility of the PCU films after surface modification and increased with increasing molecular weight of PEGMAs.
Collapse
Affiliation(s)
- Yakai Feng
- Key Laboratory of Systems Bioengineering, Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.
| | | | | | | | | | | |
Collapse
|
170
|
Thalla PK, Contreras-García A, Fadlallah H, Barrette J, De Crescenzo G, Merhi Y, Lerouge S. A versatile star PEG grafting method for the generation of nonfouling and nonthrombogenic surfaces. BIOMED RESEARCH INTERNATIONAL 2012; 2013:962376. [PMID: 23509823 PMCID: PMC3591106 DOI: 10.1155/2013/962376] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Accepted: 11/16/2012] [Indexed: 11/18/2022]
Abstract
Polyethylene glycol (PEG) grafting has a great potential to create nonfouling and nonthrombogenic surfaces, but present techniques lack versatility and stability. The present work aimed to develop a versatile PEG grafting method applicable to most biomaterial surfaces, by taking advantage of novel primary amine-rich plasma-polymerized coatings. Star-shaped PEG covalent binding was studied using static contact angle, X-ray photoelectron spectroscopy (XPS), and quartz crystal microbalance with dissipation monitoring (QCM-D). Fluorescence and QCM-D both confirmed strong reduction of protein adsorption when compared to plasma-polymerized coatings and pristine poly(ethyleneterephthalate) (PET). Moreover, almost no platelet adhesion was observed after 15 min perfusion in whole blood. Altogether, our results suggest that primary amine-rich plasma-polymerized coatings offer a promising stable and versatile method for PEG grafting in order to create nonfouling and nonthrombogenic surfaces and micropatterns.
Collapse
Affiliation(s)
- Pradeep Kumar Thalla
- Laboratory of Endovascular Biomaterials (LBeV), Research Centre, Centre Hospitalier de l'Université de Montreal (CRCHUM), 2099 Alexandre de Sève, Montreal, QC, Canada H2L 2W5
- Department of Mechanical Engineering, École de Technologie Supérieure (ÉTS), 1100 Boulevard Notre-Dame Ouest, Montreal, QC, Canada H3C 1K3
| | - Angel Contreras-García
- Department of Engineering Physics, École Polytechnique de Montreal, P.O. Box 6079, Succ. Centre-Ville, Montreal, QC, Canada H3C 3A7
| | - Hicham Fadlallah
- Laboratory of Endovascular Biomaterials (LBeV), Research Centre, Centre Hospitalier de l'Université de Montreal (CRCHUM), 2099 Alexandre de Sève, Montreal, QC, Canada H2L 2W5
- Laboratory of Thrombosis and Haemostasis Research Centre, Montreal Heart Institute, 5000 Belanger Street, Montreal, QC, Canada H1T 1C8
| | - Jérémie Barrette
- Laboratory of Endovascular Biomaterials (LBeV), Research Centre, Centre Hospitalier de l'Université de Montreal (CRCHUM), 2099 Alexandre de Sève, Montreal, QC, Canada H2L 2W5
- Department of Mechanical Engineering, École de Technologie Supérieure (ÉTS), 1100 Boulevard Notre-Dame Ouest, Montreal, QC, Canada H3C 1K3
| | - Gregory De Crescenzo
- Department of Chemical Engineering, École Polytechnique de Montreal, P.O. Box 6079, Succ. Centre-Ville, Montreal, QC, Canada H3C 3A7
| | - Yahye Merhi
- Laboratory of Thrombosis and Haemostasis Research Centre, Montreal Heart Institute, 5000 Belanger Street, Montreal, QC, Canada H1T 1C8
| | - Sophie Lerouge
- Laboratory of Endovascular Biomaterials (LBeV), Research Centre, Centre Hospitalier de l'Université de Montreal (CRCHUM), 2099 Alexandre de Sève, Montreal, QC, Canada H2L 2W5
- Department of Mechanical Engineering, École de Technologie Supérieure (ÉTS), 1100 Boulevard Notre-Dame Ouest, Montreal, QC, Canada H3C 1K3
| |
Collapse
|
171
|
Bailey BM, Fei R, Munoz-Pinto D, Hahn MS, Grunlan MA. PDMS(star)-PEG hydrogels prepared via solvent-induced phase separation (SIPS) and their potential utility as tissue engineering scaffolds. Acta Biomater 2012; 8:4324-33. [PMID: 22842033 DOI: 10.1016/j.actbio.2012.07.034] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Revised: 07/10/2012] [Accepted: 07/20/2012] [Indexed: 12/20/2022]
Abstract
Inorganic-organic hydrogels based on methacrylated star polydimethylsiloxane (PDMS(star)-MA) and diacrylated poly(ethylene glycol) (PEG-DA) macromers were prepared via solvent-induced phase separation (SIPS). The macromers were combined in a dichloromethane precursor solution and sequentially photopolymerized, dried and hydrated. The chemical and physical properties of the hydrogels were further tailored by varying the number average molecular weight (M(n)) of PEG-DA (M(n)=3.4k and 6k gmol(-1)) as well as the weight percent ratio of PDMS(star)-MA (M(n)=7k gmol(-1)) to PEG-DA from 0:100 to 20:80. Compared to analogous hydrogels fabricated from aqueous precursor solutions, SIPS produced hydrogels with a macroporous morphology, a more even distribution of PDMS(star)-MA, increased modulus and enhanced degradation rates. The morphology, swelling ratio, mechanical properties, bioactivity, non-specific protein adhesion, controlled introduction of cell adhesion, and cytocompatibility of the hydrogels were characterized. As a result of their tunable properties, this library of hydrogels is useful to study material-guided cell behavior and ultimate tissue regeneration.
Collapse
Affiliation(s)
- Brennan M Bailey
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120, USA
| | | | | | | | | |
Collapse
|
172
|
Becerra-Bayona S, Guiza-Arguello V, Qu X, Munoz-Pinto DJ, Hahn MS. Influence of select extracellular matrix proteins on mesenchymal stem cell osteogenic commitment in three-dimensional contexts. Acta Biomater 2012; 8:4397-404. [PMID: 22871641 DOI: 10.1016/j.actbio.2012.07.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2012] [Revised: 06/20/2012] [Accepted: 07/31/2012] [Indexed: 12/31/2022]
Abstract
Growth factors have been shown to be powerful mediators of mesenchymal stem cell (MSC) osteogenic differentiation. However, their use in tissue engineered scaffolds not only can be costly but also can induce undesired responses in surrounding tissues. Thus, the ability to specifically promote MSC osteogenic differentiation in the absence of exogenous growth factors via the manipulation of scaffold material properties would be beneficial. The current work examines the influence of select extracellular matrix (ECM) proteins on MSC osteogenesis toward the goal of developing scaffolds with intrinsically osteoinductive properties. Fibrinogen (FG), fibronectin (FN) and laminin-1 (LN) were chosen for evaluation due to their known roles in bone morphogenesis or bone fracture healing. These proteins were conjugated into poly(ethylene glycol) diacrylate (PEGDA) hydrogels and their effects on encapsulated 10T½ MSCs were evaluated. Specifically, following 1week of culture, mid-term markers of various MSC lineages were examined in order to assess the strength and specificity of the observed osteogenic responses. PEG-LN gels demonstrated increased levels of the osteogenic transcription factor osterix relative to day 0 levels. In addition, PEG-FG and PEG-LN gels were associated with increased deposition of bone ECM protein osteocalcin relative to PEG-FN gels and day 0. Importantly, the osteogenic response associated with FG and LN appeared to be specific in that markers for chondrocytic, smooth muscle cell and adipocytic lineages were not similarly elevated relative to day 0 in these gels. To gain insight into the integrin dynamics underlying the observed differentiation results, initial integrin adhesion and temporal alterations in cell integrin profiles were evaluated. The associated results suggest that α(2), α(v) and α(6) integrin subunits may play key roles in integrin-mediated osteogenesis.
Collapse
|
173
|
|
174
|
Chen J, Wang J, Qi P, Li X, Ma B, Chen Z, Li Q, Zhao Y, Xiong K, Maitz MF, Huang N. Biocompatibility studies of poly(ethylene glycol)–modified titanium for cardiovascular devices. J BIOACT COMPAT POL 2012. [DOI: 10.1177/0883911512461108] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The rapid protein adsorption on a material surface causes blood coagulation, platelet activation, and complement system activation, which poses a risk for failure of cardiovascular devices. In this study, a chemically hydroxylated titanium surface was aminosilanized and covalently grafted with poly(ethylene glycol). The reaction conditions on the grafted quantity were studied by the respective amine and carboxyl densities. The blood compatibility of the PEGylated surfaces with different poly(ethylene glycol) densities and chain lengths was evaluated; the PEGylated surfaces with higher grafted density and longer chain length had less fibrinogen adsorption, less fibrinogen γ-chain exposed, less adherent platelets, and lower activation of the adherent platelets. In addition to the influence on blood, the longer chain PEGylated surfaces resisted, not only smooth muscle cell attachment and proliferation, but also macrophage attachment and death. This method is a good candidate for improving cardiovascular implant surfaces.
Collapse
Affiliation(s)
- Jialong Chen
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
- College of Stomatology, Anhui Medical University, Hefei, China
| | - Juan Wang
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
| | - Pengkai Qi
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
| | - Xin Li
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
| | - Baolong Ma
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, China
| | - Zhuoyue Chen
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
| | - Quanli Li
- College of Stomatology, Anhui Medical University, Hefei, China
| | - Yuancong Zhao
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
| | - Kaiqin Xiong
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
| | - Manfred F Maitz
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
- Max Bergmann Center of Biomaterials Dresden, Leibniz Institute of Polymer Research Dresden, Dresden, Germany
| | - Nan Huang
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu, China
| |
Collapse
|
175
|
Kurihara Y, Takama M, Sekiya T, Yoshihara Y, Ooya T, Takeuchi T. Fabrication of carboxylated silicon nitride sensor chips for detection of antigen-antibody reaction using microfluidic reflectometric interference spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:13609-13615. [PMID: 22966896 DOI: 10.1021/la302221y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this study, we report label-free detection of alpha-fetoprotein (AFP), which has been used as a biomarker for hepatocellular carcinoma, by a microfluidic reflectometric interference spectroscopy (RIfS) system adopting a simple halogen light source and an inexpensive silicon-based sensor chip. Introduction of carboxy groups on a silicon nitride sensor chip to immobilize anti-AFP monoclonal antibody (anti-AFP) was carried out simply by immersion in aqueous solution containing triethoxysilylpropylmaleamic acid bearing a carboxy group and a silanol group. The RIfS system with the anti-AFP-immobilized sensor chip was found to give a reversible response through 100 on/off cycles using a regeneration buffer with high reproducibility (coefficient of variation (CV) = 5.7%). The limit of detection (LOD) of AFP was 100 ng mL(-1), and the measurement range spanned 3 orders of magnitude. Furthermore, the sensor chip showed no cross-reactivity with human serum albumin, Immunoglobulin G, transferrin, or fibrinogen at 100 μg mL(-1) without the use of blocking reagents such as bovine serum albumin. Consequently, the proposed RIfS system is a potentially effective tool for biomarker detection and in vitro diagnostics.
Collapse
Affiliation(s)
- Yoshikazu Kurihara
- Graduate School of Engineering, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | | | | | | | | | | |
Collapse
|
176
|
Agarwal A, Luria E, Deng X, Lahann J, Hess H. Landing Rate Measurements to Detect Fibrinogen Adsorption to Non-fouling Surfaces. Cell Mol Bioeng 2012. [DOI: 10.1007/s12195-012-0239-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
|
177
|
Uhlig K, Boysen B, Lankenau A, Jaeger M, Wischerhoff E, Lutz JF, Laschewsky A, Duschl C. On the influence of the architecture of poly(ethylene glycol)-based thermoresponsive polymers on cell adhesion. BIOMICROFLUIDICS 2012; 6:24129. [PMID: 23761842 PMCID: PMC3386990 DOI: 10.1063/1.4729130] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 05/28/2012] [Indexed: 05/25/2023]
Abstract
Thermoresponsive polymer surface coatings are a promising tool for cell culture applications. They allow for a mild way of cell detachment that preserves the activity of membrane proteins-a prerequisite for reliable cell analysis. To enlarge the application range of these coatings to cells with different adhesion properties, we synthesized various novel poly(ethylene glycol)-based thermoresponsive polymers and describe how (i) their chemical structure and (ii) their surface density affect their efficiency. In order to quantify the influence of both factors, the time for cell spreading and rounding efficiency were observed. As a result, efficiency of cell rounding, which is closely correlated to cell detachment, is less affected by both factors than the time needed for cell spreading. This time can effectively be adjusted by the molecular architecture which includes the length of the polymer backbone and the side chains. Based on this work, recommendations are given for future optimization of functionality of thermoresponsive polymer coatings for cell culture applications.
Collapse
Affiliation(s)
- Katja Uhlig
- Fraunhofer Institute for Biomedical Engineering (IBMT), Potsdam, Germany
| | | | | | | | | | | | | | | |
Collapse
|
178
|
Sask KN, Berry LR, Chan AKC, Brash JL. Polyurethane modified with an antithrombin-heparin complex via polyethylene oxide linker/spacers: Influence of PEO molecular weight and PEO-ATH bond on catalytic and direct anticoagulant functions. J Biomed Mater Res A 2012; 100:2821-8. [DOI: 10.1002/jbm.a.34218] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 03/28/2012] [Accepted: 04/03/2012] [Indexed: 11/11/2022]
|
179
|
Wang Q, Uzunoglu E, Wu Y, Libera M. Self-assembled poly(ethylene glycol)-co-acrylic acid microgels to inhibit bacterial colonization of synthetic surfaces. ACS APPLIED MATERIALS & INTERFACES 2012; 4:2498-506. [PMID: 22519439 DOI: 10.1021/am300197m] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We explored the use of self-assembled microgels to inhibit the bacterial colonization of synthetic surfaces both by modulating surface cell adhesiveness at length scales comparable to bacterial dimensions (∼1 μm) and by locally storing/releasing an antimicrobial. Poly(ethylene glycol) [PEG] and poly(ethylene glycol)-co-acrylic acid [PEG-AA] microgels were synthesized by suspension photopolymerization. Consistent with macroscopic gels, a pH dependence of both zeta potential and hydrodynamic diameter was observed in AA-containing microgels but not in pure PEG microgels. The microgels were electrostatically deposited onto poly(l-lysine) (PLL) primed silicon to form submonolayer surface coatings. The microgel surface density could be controlled via the deposition time and the microgel concentration in the parent suspension. In addition to their intrinsic antifouling properties, after deposition, the microgels could be loaded with a cationic antimicrobial peptide (L5) because of favorable electrostatic interactions. Loading was significantly higher in PEG-AA microgels than in pure PEG microgels. The modification of PLL-primed Si by unloaded PEG-AA microgels reduced the short-term (6 h) S. epidermidis surface colonization by a factor of 2, and the degree of inhibition increased when the average spacing between microgels was reduced. Postdeposition L5 peptide loading into microgels further reduced bacterial colonization to the extent that, after 10 h of S. epidermidis culture in tryptic soy broth, the colonization of L5-loaded PEG-AA microgel-modified Si was comparable to the very small level of colonization observed on macroscopic PEG gel controls. The fact that these microgels can be deposited by a nonline-of-sight self-assembly process and hinder bacterial colonization opens the possibility of modifying the surfaces of topographically complex biomedical devices and reduces the rate of biomaterial-associated infection.
Collapse
Affiliation(s)
- Qichen Wang
- Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, New Jersey 07030, USA
| | | | | | | |
Collapse
|
180
|
Klenkler BJ, Chen H, Chen Y, Brook MA, Sheardown H. A high-density PEG interfacial layer alters the response to an EGF tethered polydimethylsiloxane surface. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 19:1411-24. [PMID: 18973720 DOI: 10.1163/156856208786140346] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- B. J. Klenkler
- a Department of Chemical Engineering, McMaster University, 1280 Main St. West, Hamilton, ON, Canada L8S 4L7
| | - H. Chen
- b Department of Chemical Engineering, McMaster University, 1280 Main St. West, Hamilton, ON, Canada L8S 4L7; School of Biomedical Engeineering, McMaster University, 1280 Main St. West, Hamilton, ON, Canada L8S 4L7
| | - Y. Chen
- c School of Biomedical Engeineering, McMaster University, 1280 Main St. West, Hamilton, ON, Canada L8S 4L7
| | - M. A. Brook
- d School of Biomedical Engeineering, McMaster University, 1280 Main St. West, Hamilton, ON, Canada L8S 4L7
| | - H. Sheardown
- e Department of Chemical Engineering, McMaster University, 1280 Main St. West, Hamilton, ON, Canada L8S 4L7
| |
Collapse
|
181
|
Li Z, Yang X, Wu L, Chen Z, Lin Y, Xu K, Chen GQ. Synthesis, Characterization and Biocompatibility of Biodegradable Elastomeric Poly(ether-ester urethane)s Based on Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) and Poly(ethylene glycol) via Melting Polymerization. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 20:1179-202. [DOI: 10.1163/156856209x452944] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Zibiao Li
- a Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, P.R. China
| | - Xiaodi Yang
- b Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, P.R. China
| | - Linping Wu
- c Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, P.R. China
| | - Zhifei Chen
- d Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, P.R. China
| | - Yuting Lin
- e Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, P.R. China
| | - Kaitian Xu
- f Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, P.R. China
| | - Guo-Qiang Chen
- g Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, P.R. China; Department of Biological Science and Biotechnology, Tsinghua University, Beijing 100084, P.R. China
| |
Collapse
|
182
|
Jones JA, Dadsetan M, Collier TO, Ebert M, Stokes KS, Ward RS, Hiltner PA, Anderson JM. Macrophage behavior on surface-modified polyurethanes. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 15:567-84. [PMID: 15264659 DOI: 10.1163/156856204323046843] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adherent macrophages and foreign body giant cells (FBGCs) are known to release degradative molecules that can be detrimental to the long-term biostability of polyurethanes. The modification of polyurethanes using surface modifying endgroups (SMEs) and/or the incorporation of silicone into the polyurethane soft segments may alter macrophage adhesion, fusion and apoptosis resulting in improved long-term biostability. An in vitro study of macrophage adhesion, fusion and apoptosis was performed on polyurethanes modified with fluorocarbon SMEs, polyethylene oxide (PEO) SMEs, or poly(dimethylsiloxane) (PDMS) co-soft segment and SMEs. The fluorocarbon SME and PEO SME modifications were shown to have no effect on macrophage adhesion and activity, while silicone modification had varied effects. Macrophages were capable of adapting to the surface and adhering in a similar manner to the silicone-modified and unmodified polyurethanes. In the absence of IL-4, macrophage fusion was comparable on the modified and unmodified polyurethanes, while macrophage apoptosis was promoted on the silicone modified surfaces. In contrast, when exposed to IL-4, a cytokine known to induce FBGC formation, silicone modification resulted in more macrophage fusion to form foreign body giant cells. In conclusion, fluorocarbon SME and PEO SME modification does not affect macrophage adhesion, fusion and apoptosis, while silicone modification is capable of mediating macrophage fusion and apoptosis. Silicone modification may be utilized to direct the fate of adherent macrophages towards FBGC formation or cell death through apoptosis.
Collapse
Affiliation(s)
- Jacqueline A Jones
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | | | | | | | | | | | | | | |
Collapse
|
183
|
Partitioning of haemoglobin and bovine serum albumin from whole bovine blood using aqueous two-phase systems. Sep Purif Technol 2012. [DOI: 10.1016/j.seppur.2012.02.032] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
184
|
Browning M, Dempsey D, Guiza V, Becerra S, Rivera J, Russell B, Höök M, Clubb F, Miller M, Fossum T, Dong J, Bergeron A, Hahn M, Cosgriff-Hernandez E. Multilayer vascular grafts based on collagen-mimetic proteins. Acta Biomater 2012; 8:1010-21. [PMID: 22142564 DOI: 10.1016/j.actbio.2011.11.015] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 10/14/2011] [Accepted: 11/11/2011] [Indexed: 12/20/2022]
Abstract
A major roadblock in the development of an off-the-shelf, small-caliber vascular graft is achieving rapid endothelialization of the conduit while minimizing the risk of thrombosis, intimal hyperplasia, and mechanical failure. To address this need, a collagen-mimetic protein derived from group A Streptococcus, Scl2.28 (Scl2), was conjugated into a poly(ethylene glycol) (PEG) hydrogel to generate bioactive hydrogels that bind to endothelial cells (ECs) and resist platelet adhesion. The PEG-Scl2 hydrogel was then reinforced with an electrospun polyurethane mesh to achieve suitable biomechanical properties. In the current study, initial evaluation of this multilayer design as a potential off-the-shelf graft was conducted. First, electrospinning parameters were varied to achieve composite burst pressure, compliance, and suture retention strength that matched reported values of saphenous vein autografts. Composite stability following drying, sterilization, and physiological conditioning under pulsatile flow was then demonstrated. Scl2 bioactivity was also maintained after drying and sterilization as indicated by EC adhesion and spreading. Evaluation of platelet adhesion, aggregation, and activation indicated that PEG-Scl2 hydrogels had minimal platelet interactions and thus appear to provide a thromboresistant blood contacting layer. Finally, evaluation of EC migration speed demonstrated that PEG-Scl2 hydrogels promoted higher migration speeds than PEG-collagen analogs and that migration speed was readily tuned by altering protein concentration. Collectively, these results indicate that this multilayer design warrants further investigation and may have the potential to improve on current synthetic options.
Collapse
|
185
|
Browning MB, Cosgriff-Hernandez E. Development of a biostable replacement for PEGDA hydrogels. Biomacromolecules 2012; 13:779-86. [PMID: 22324325 DOI: 10.1021/bm201707z] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The exceptional tunability of poly(ethylene glycol) (PEG) hydrogel chemical, mechanical, and biological properties enables their successful use in a wide range of biomedical applications. Although PEG diacrylate (PEGDA) hydrogels are often used as nondegradable controls in short-term in vitro studies, it is widely acknowledged that the hydrolytically labile esters formed upon acrylation of the PEG diol make them susceptible to slow degradation in vivo. A PEG hydrogel system that maintains the desirable properties of PEGDA while improving biostability would be valuable in preventing degradation-related failure of gel-based devices in long-term in vivo applications. To this end, PEG diacrylamide (PEGDAA) hydrogels were synthesized and characterized in quantitative comparison to traditional PEGDA hydrogels. It was found that PEGDAA hydrogel modulus and swelling can be tuned over a similar range and to comparable degrees as PEGDA hydrogels with changes in macromer molecular weight and concentration. Additionally, PEGDAA cytocompatibility, low cell adhesion, and capacity for incorporation of bioactivity were analogous to that of PEGDA. In vitro hydrolytic degradation studies showed that the amide-based PEGDAA had significantly increased biostability relative to PEGDA. Overall, these findings indicate that PEGDAA hydrogels are a suitable replacement for PEGDA hydrogels with enhanced hydrolytic resistance. In addition, these studies provide a quantitative measure of the hydrolytic degradation rate of PEGDA hydrogels which was previously lacking in the literature.
Collapse
Affiliation(s)
- Mary Beth Browning
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843-3120, United States
| | | |
Collapse
|
186
|
Zuo Y, Xiao W, Chen X, Tang Y, Luo H, Fan H. Bottom-up approach to build osteon-like structure by cell-laden photocrosslinkable hydrogel. Chem Commun (Camb) 2012; 48:3170-2. [PMID: 22331209 DOI: 10.1039/c2cc16744a] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Based on photocrosslinkable PEGDMA and GelMA hydrogels, two "bottom-up" approaches ("circle-and-cross" and "layer-by-layer") were successfully developed to construct osteon-like structures with microchannel networks. Significantly, the "layer-by-layer" approach employing the GelMA hydrogel with a higher biocompatibility was more favorable for building biomimetic osteon.
Collapse
Affiliation(s)
- Yicong Zuo
- National Engineering Research Center for Biomaterials, Sichuan University, 610064, Chengdu, China
| | | | | | | | | | | |
Collapse
|
187
|
Biofunctionalization of titanium with PEG and anti-CD34 for hemocompatibility and stimulated endothelialization. J Colloid Interface Sci 2012; 368:636-47. [DOI: 10.1016/j.jcis.2011.11.039] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 11/15/2011] [Accepted: 11/16/2011] [Indexed: 11/23/2022]
|
188
|
Sask KN, Berry LR, Chan AKC, Brash JL. Modification of polyurethane surface with an antithrombin-heparin complex for blood contact: influence of molecular weight of polyethylene oxide used as a linker/spacer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:2099-2106. [PMID: 22149666 DOI: 10.1021/la203821g] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Polyurethane (PU) was modified using isocyanate chemistry to graft polyethylene oxide (PEO) of various molecular weights (range 300-4600). An antithrombin-heparin (ATH) covalent complex was subsequently attached to the free PEO chain ends, which had been functionalized with N-hydroxysuccinimide (NHS) groups. Surfaces were characterized by water contact angle and X-ray photoelectron spectroscopy (XPS) to confirm the modifications. Adsorption of fibrinogen from buffer was found to decrease by ~80% for the PEO-modified surfaces compared to the unmodified PU. The surfaces with ATH attached to the distal chain end of the grafted PEO were equally protein resistant, and when the data were normalized to the ATH surface density, PEO in the lower MW range showed greater protein resistance. Western blots of proteins eluted from the surfaces after plasma contact confirmed these trends. The uptake of ATH on the PEO-modified surfaces was greatest for the PEO of lower MW (300 and 600), and antithrombin binding from plasma (an indicator of heparin anticoagulant activity) was highest for these same surfaces. The PEO-ATH- and PEO-modified surfaces also showed low platelet adhesion from flowing whole blood. It is concluded that for the PEO-ATH surfaces, PEO in the low MW range, specifically MW 600, may be optimal for achieving an appropriate balance between resistance to nonspecific protein adsorption and the ability to take up ATH and bind antithrombin in subsequent blood contact.
Collapse
Affiliation(s)
- Kyla N Sask
- School of Biomedical Engineering, McMaster University, 1280 Main Street West, Hamilton, ON, Canada L8S 4K1
| | | | | | | |
Collapse
|
189
|
González-Ortega O, Porath J, Guzmán R. Adsorption of peptides and small proteins with control access polymer permeation to affinity binding sites. Part I: Polymer permeation-immobilized metal ion affinity chromatography separation adsorbents with polyethylene glycol and immobilized metal ions. J Chromatogr A 2012; 1227:115-25. [PMID: 22281505 DOI: 10.1016/j.chroma.2011.12.091] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 12/09/2011] [Accepted: 12/27/2011] [Indexed: 10/14/2022]
Abstract
Despite the many efforts to develop efficient protein purification techniques, the isolation of peptides and small proteins on a larger than analytical scale remains a significant challenge. Recovery of small biomolecules from diluted complex biological mixtures, such as human serum, employing porous adsorbents is a difficult task mainly due to the presence of concentrated large biomolecules that can add undesired effects in the system such as blocking of adsorbent pores, impairing diffusion of small molecules, or competition for adsorption sites. Adsorption and size exclusion chromatography (AdSEC) controlled access media, using polyethylene glycol (PEG) as a semi-permeable barrier on a polysaccharide matrix, have been developed and explored in this work to overcome such effects and to preferentially adsorb small molecules while rejecting large ones. In the first part of this work, adsorption studies were performed with small peptides and proteins from synthetic mixtures using controlled access polymer permeation adsorption (CAPPA) media created by effectively grafting PEG on an immobilized metal affinity chromatography (IMAC) agarose resin, where chelating agents and immobilized metal ions were used as the primary affinity binding sites. Synthetic mixtures consisted of bovine serum albumin (BSA) with small proteins, peptides, amino acids (such as histidine or Val⁴-Angiotensin III), and small molecules-spiked human serum. The synthesized hybrid adsorbent consisted of agarose beads modified with iminodiacetic (IDA) groups, loaded with immobilized Cu(II) ions, and PEG. These CAPPA media with grafted PEG on the interior and exterior surfaces of the agarose matrix were effective in rejecting high molecular weight proteins. Different PEG grafting densities and PEG of different molecular weight were tested to determine their effect in rejecting and controlling adsorbent permeation properties. Low grafting density of high molecular weight PEG was found to be as effective as high grafting density of low molecular weight PEG in the rejecting properties of the semi-permeable synthesized media.
Collapse
Affiliation(s)
- Omar González-Ortega
- Department of Chemical and Environmental Engineering, The University of Arizona, Tucson, AZ 85721,USA
| | | | | |
Collapse
|
190
|
Wang Y, Subbiahdoss G, de Vries J, Libera M, van der Mei HC, Busscher HJ. Effect of adsorbed fibronectin on the differential adhesion of osteoblast-like cells and Staphylococcus aureus with and without fibronectin-binding proteins. BIOFOULING 2012; 28:1011-1021. [PMID: 23004018 DOI: 10.1080/08927014.2012.725471] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The influence of fibronectin (Fn) coated surfaces patterned with poly(ethylene glycol) microgels having inter-gel spacings between 0.5 and 3.0 μm on the adhesion of Staphylococcus aureus strains with and without Fn-binding proteins and cellular adhesion/spreading was investigated. Quantitative force measurements between a S. aureus cell and a patterned surface showed that the adhesion force between the bacterium and the patterned surface increased substantially after Fn adsorption, regardless of the strain used, but decreased with decreasing inter-gel spacing. In flow-chamber experiments, the Fn-binding strain adhered at a higher rate after Fn adsorption than the strain lacking Fn-binding proteins. In both cases, the adhesion rates decreased with decreasing inter-gel spacing. Osteoblast-like cells could bind to patterned surfaces despite the microgels, and adsorbed Fn substantially amplified this effect. Even under highly non-adhesive conditions associated with closely spaced microgels, adsorbed Fn preserves a window of inter-gel spacing around 1 μm where the adhesion of staphylococcal cells is hindered while cells can still adhere and spread.
Collapse
Affiliation(s)
- Y Wang
- Department of Biomedical Engineering, W.J. Kolff Institute, University Medical Center and University of Groningen, The Netherlands
| | | | | | | | | | | |
Collapse
|
191
|
Binazadeh M, Kabiri M, Unsworth LD. Poly(ethylene glycol) and Poly(carboxy betaine) Based Nonfouling Architectures: Review and Current Efforts. ACS SYMPOSIUM SERIES 2012. [DOI: 10.1021/bk-2012-1120.ch028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
192
|
Hawkins ML, Grunlan MA. The protein resistance of silicones prepared with a PEO-silane amphiphile. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm32322b] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
193
|
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.
Collapse
|
194
|
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.
Collapse
|
195
|
Harris CA, McAllister JP. What We Should Know About the Cellular and Tissue Response Causing Catheter Obstruction in the Treatment of Hydrocephalus. Neurosurgery 2011; 70:1589-601; discussion 1601-2. [DOI: 10.1227/neu.0b013e318244695f] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
The treatment of hydrocephalus by cerebrospinal fluid shunting is plagued by ventricular catheter obstruction. Shunts can become obstructed by cells originating from tissue normal to the brain or by pathological cells in the cerebrospinal fluid for a variety of reasons. In this review, the authors examine ventricular catheter obstruction and identify some of the modifications to the ventricular catheter that may alter the mechanical and chemical cues involved in obstruction, including alterations to the surgical strategy, modifications to the chemical surface of the catheter, and changes to the catheter architecture. It is likely a combination of catheter modifications that will improve the treatment of hydrocephalus by prolonging the life of ventricular catheters to improve patient outcome.
Collapse
Affiliation(s)
- Carolyn A. Harris
- Department of Neurosurgery, Division of Pediatric Neurosurgery, University of Utah, Salt Lake City, Utah
- Department of Bioengineering, University of Utah, Salt Lake City, Utah
| | - James P. McAllister
- Department of Neurosurgery, Division of Pediatric Neurosurgery, University of Utah, Salt Lake City, Utah
- Department of Bioengineering, University of Utah, Salt Lake City, Utah
- Department of Physiology, University of Utah, Salt Lake City, Utah
| |
Collapse
|
196
|
Dimitriou MD, Zhou Z, Yoo HS, Killops KL, Finlay JA, Cone G, Sundaram HS, Lynd NA, Barteau KP, Campos LM, Fischer DA, Callow ME, Callow JA, Ober CK, Hawker CJ, Kramer EJ. A general approach to controlling the surface composition of poly(ethylene oxide)-based block copolymers for antifouling coatings. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:13762-13772. [PMID: 21888355 DOI: 10.1021/la202509m] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
To control the surface properties of a polystyrene-block-poly(ethylene oxide) diblock copolymer, perfluorinated chemical moieties were specifically incorporated into the block copolymer backbone. A polystyrene-block-poly[(ethylene oxide)-stat-(allyl glycidyl ether)] [PS-b-P(EO-stat-AGE)] statistical diblock terpolymer was synthesized with varying incorporations of allyl glycidyl ether (AGE) in the poly(ethylene oxide) block from 0 to 17 mol %. The pendant alkenes of the AGE repeat units were subsequently functionalized by thiol-ene chemistry with 1H,1H,2H,2H-perfluorooctanethiol, yielding fluorocarbon-functionalized AGE (fAGE) repeat units. (1)H NMR spectroscopy and size-exclusion chromatography indicated well-defined structures with complete functionalization of the pendant alkenes. The surfaces of the polymer films were characterized after spray coating by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure spectroscopy (NEXAFS), showing that the P(EO-stat-fAGE) block starts to compete with polystyrene to populate the surface after only 1 mol % incorporation of fAGE. Increasing the incorporation of fAGE led to an increased amount of perfluorocarbons on the surface and a decrease in the concentration of PS. At a fAGE incorporation of 8 mol %, PS was not detected at the surface, as measured by NEXAFS spectroscopy. Water contact angles measured by the captive-air-bubble technique showed the underwater surfaces to be dynamic, with advancing and receding contact angles varying by >20°. Protein adsorption studies demonstrated that the fluorinated surfaces effectively prevent nonspecific binding of proteins relative to an unmodified PS-b-PEO diblock copolymer. In biological systems, settlement of spores of the green macroalga Ulva was significantly lower for the fAGE-incorporated polymers compared to the unmodified diblock and a polydimethylsiloxane elastomer standard. Furthermore, the attachment strength of sporelings (young plants) of Ulva was also reduced for the fAGE-containing polymers, affirming their potential as fouling-release coatings.
Collapse
Affiliation(s)
- Michael D Dimitriou
- Materials Department, University of California, Santa Barbara, California 93106, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
197
|
Bailey BM, Hui V, Fei R, Grunlan MA. Tuning PEG-DA hydrogel properties via solvent-induced phase separation (SIPS)(). ACTA ACUST UNITED AC 2011; 21:18776-18782. [PMID: 22956857 DOI: 10.1039/c1jm13943f] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Poly(ethylene glycol) diacrylate (PEG-DA) hydrogels are widely utilized to probe cell-material interactions and ultimately for a material-guided approach to tissue regeneration. In this study, PEG-DA hydrogels were fabricated via solvent-induced phase separation (SIPS) to obtain hydrogels with a broader range of tunable physical properties including morphology (e.g. porosity), swelling and modulus (G'). In contrast to conventional PEG-DA hydrogels prepared from an aqueous precursor solution, the reported SIPS protocol utilized a dichloromethane (DCM) precursor solution which was sequentially photopolymerized, dried and hydrated. Physical properties were further tailored by varying the PEG-DA wt% concentration (5 wt%-25 wt%) and M(n) (3.4k and 6k g mol (-1)). SIPS produced PEG-DA hydrogels with a macroporous morphology as well as increased G' values versus the corresponding conventional PEG-DA hydrogels. Notably, since the total swelling was not significantly changed versus the corresponding conventional PEG-DA hydrogels, pairs or series of hydrogels represent scaffolds in which morphology and hydration or G' and hydration are uncoupled. In addition, PEG-DA hydrogels prepared via SIPS exhibited enhanced degradation rates.
Collapse
Affiliation(s)
- Brennan Margaret Bailey
- Texas A&M University, Department of Biomedical Engineering, Materials Science and Engineering Program, 3120 TAMU College Station, TX, USA. ; Tel: (+979) 845-2406
| | | | | | | |
Collapse
|
198
|
Wu Z, Chen H, Liu X, Brash JL. Protein-Resistant and Fibrinolytic Polyurethane Surfaces. Macromol Biosci 2011; 12:126-31. [DOI: 10.1002/mabi.201100211] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 08/12/2011] [Indexed: 12/18/2022]
|
199
|
Curley JL, Moore MJ. Facile micropatterning of dual hydrogel systems for 3D models of neurite outgrowth. J Biomed Mater Res A 2011; 99:532-43. [PMID: 21936043 DOI: 10.1002/jbm.a.33195] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 05/04/2011] [Accepted: 06/10/2011] [Indexed: 11/10/2022]
Abstract
Understanding how microenvironmental factors influence neurite growth is important to inform studies in nerve regeneration, plasticity, development, and neurophysiology. In vitro models attempting to more accurately mimic the physiological environment by provision of a 3D growth matrix may provide useful foundations. Some limitations of thick 3D culture models include hampered solute transport, less-robust neurite growth than on 2D substrates, and difficulty in achieving spatial control of growth. To this end, we describe a 3D dual hydrogel model for embryonic rat day 15 dorsal root ganglion tissue explant growth using a digital micromirror device for dynamic mask projection photolithography. The photolithography method developed allowed simple, reproducible, one-step fabrication of thick hydrogel constructs on a variety of substrates, including permeable cell culture inserts. The relationships between projected mask size, crosslinked hydrogel resolution, and gel thickness were characterized, and resolution was found generally to decrease with increasing gel thickness. Cell viability in thick (481 μm) hydrogel constructs was significantly greater on permeable supports than glass, suggesting transport limitations were somewhat alleviated. The observed neurite growth was abundant and occurred in a spatially controlled manner throughout the 3D environment, a crucial step in the quest for a more effective biomimetic model of neurite outgrowth.
Collapse
Affiliation(s)
- J Lowry Curley
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana 70118, USA
| | | |
Collapse
|
200
|
Tian L, George SC. Biomaterials to prevascularize engineered tissues. J Cardiovasc Transl Res 2011; 4:685-98. [PMID: 21892744 DOI: 10.1007/s12265-011-9301-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 06/20/2011] [Indexed: 11/30/2022]
Abstract
Tissue engineering promises to restore tissue and organ function following injury or failure by creating functional and transplantable artificial tissues. The development of artificial tissues with dimensions that exceed the diffusion limit (1-2 mm) will require nutrients and oxygen to be delivered via perfusion (or convection) rather than diffusion alone. One strategy of perfusion is to prevascularize tissues; that is, a network of blood vessels is created within the tissue construct prior to implantation, which has the potential to significantly shorten the time of functional vascular perfusion from the host. The prevascularized network of vessels requires an extracellular matrix or scaffold for 3D support, which can be either natural or synthetic. This review surveys the commonly used biomaterials for prevascularizing 3D tissue engineering constructs.
Collapse
Affiliation(s)
- Lei Tian
- The Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, CA, USA
| | | |
Collapse
|