51
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Lee C, Lee SY. Mussel-inspired bolaamphiphile sticky self-assemblies for the preparation of magnetic nanoparticles. Colloids Surf B Biointerfaces 2015; 127:89-95. [DOI: 10.1016/j.colsurfb.2014.11.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 10/30/2014] [Accepted: 11/16/2014] [Indexed: 10/24/2022]
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52
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Nakajima H, Kondo M, Nakane T, Abe S, Nakao T, Watanabe Y, Ueno T. Construction of an enterobactin analogue with symmetrically arranged monomer subunits of ferritin. Chem Commun (Camb) 2015; 51:16609-12. [DOI: 10.1039/c5cc06904a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The symmetric arrangement of ferritin subunits served as a versatile foundation to produce a symmetric coordination space with designed ligands.
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Affiliation(s)
- Hiroshi Nakajima
- Division of Molecular Materials Science
- Graduate School of Science
- Osaka City University
- Osaka
- Japan
| | - Mio Kondo
- Department of Chemistry
- Graduate School of Science
- Nagoya University
- Nagoya
- Japan
| | - Taiki Nakane
- Department of Biomolecular Engineering
- Graduate School of Bioscience and Biotechnology
- Tokyo Institute of Technology
- Midori-ku
- Japan
| | - Satoshi Abe
- Department of Biomolecular Engineering
- Graduate School of Bioscience and Biotechnology
- Tokyo Institute of Technology
- Midori-ku
- Japan
| | - Takahiro Nakao
- Department of Chemistry
- Graduate School of Science
- Nagoya University
- Nagoya
- Japan
| | | | - Takafumi Ueno
- Department of Biomolecular Engineering
- Graduate School of Bioscience and Biotechnology
- Tokyo Institute of Technology
- Midori-ku
- Japan
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53
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Cencer M, Murley M, Liu Y, Lee BP. Effect of Nitro-Functionalization on the Cross-Linking and Bioadhesion of Biomimetic Adhesive Moiety. Biomacromolecules 2014; 16:404-10. [PMID: 25495043 PMCID: PMC4294588 DOI: 10.1021/bm5016333] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
Dopamine
mimics the exceptional moisture-resistant adhesive properties
of the amino acid, DOPA, found in adhesive proteins secreted by marine
mussels. The catechol side chain of dopamine was functionalized with
a nitro-group, and the effect of the electron withdrawing group modification
on the cross-linking chemistry and bioadhesive properties of the adhesive
moiety was evaluated. Both nitrodopamine and dopamine were covalently
attached as a terminal group onto an inert, 4-armed poly(ethylene
glygol) (PEG-ND and PEG-D, respectively). PEG-ND and PEG-D exhibited
different dependence on the concentration of NaIO4 and
pH, which affected the curing rate, mechanical properties, and adhesive
performance of these biomimetic adhesives differently. PEG-ND cured
instantly and its bioadhesive properties were minimally affected by
the change in pH (5.7–8) within the physiological range. Under
mildly acidic conditions (pH 5.7 and 6.7), PEG-ND outperformed PEG-D
in lap shear adhesion testing using wetted pericardium tissues. However,
nitrodopamine only formed dimers, which resulted in the formation
of loosely cross-linked network and adhesive with reduced cohesive
properties. UV–vis spectroscopy further confirmed nitrodopamine’s
ability for rapid dimer formation. The ability for nitrodopamine to
rapidly cure and adhere to biological substrates in an acidic pH make
it suitable for designing adhesive biomaterials targeted at tissues
that are more acidic (i.e., subcutaneous, dysoxic, or tumor tissues).
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Affiliation(s)
- Morgan Cencer
- Departments of †Chemistry and ‡Biomedical Engineering, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Meridith Murley
- Departments of †Chemistry and ‡Biomedical Engineering, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Yuan Liu
- Departments of †Chemistry and ‡Biomedical Engineering, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Bruce P. Lee
- Departments of †Chemistry and ‡Biomedical Engineering, Michigan Technological University, Houghton, Michigan 49931, United States
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54
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Yang J, Cohen Stuart MA, Kamperman M. Jack of all trades: versatile catechol crosslinking mechanisms. Chem Soc Rev 2014; 43:8271-98. [PMID: 25231624 DOI: 10.1039/c4cs00185k] [Citation(s) in RCA: 410] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Catechols play an important role in many natural systems. They are known to readily interact with both organic (e.g., amino acids) and inorganic (e.g., metal ions, metal oxides) compounds, thereby providing a powerful system for protein curing. Catechol crosslinked protein networks, such as sclerotized cuticle and byssal threads of the mussel, have been shown to exhibit excellent mechanical properties. A lot of effort has been devoted to mimicking the natural proteins using synthetic catechol-functionalized polymers. Despite the success in developing catechol-functionalized materials, the crosslinking chemistry of catechols is still a subject of debate. To develop materials with controlled and superior properties, a clear understanding of the crosslinking mechanism of catechols is of vital importance. This review describes the crosslinking pathways of catechol and derivatives in both natural and synthetic systems. We discuss existing pathways of catechol crosslinking and parameters that affect the catechol chemistry in detail. This overview will point towards a rational direction for further investigation of the complicated catechol chemistry.
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Affiliation(s)
- Juan Yang
- Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703HB Wageningen, The Netherlands.
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55
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Yang C, Wu H, Shi J, Wang X, Xie J, Jiang Z. Preparation of Dopamine/Titania Hybrid Nanoparticles through Biomimetic Mineralization and Titanium(IV)–Catecholate Coordination for Enzyme Immobilization. Ind Eng Chem Res 2014. [DOI: 10.1021/ie501734g] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
| | - Hong Wu
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Jiafu Shi
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | | | | | - Zhongyi Jiang
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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56
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Lee BP, Konst S. Novel hydrogel actuator inspired by reversible mussel adhesive protein chemistry. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:3415-3419. [PMID: 24596273 DOI: 10.1002/adma.201306137] [Citation(s) in RCA: 186] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 01/21/2014] [Indexed: 06/03/2023]
Abstract
A novel hydrogel actuator that combines ionoprinting techniques with reversible catechol-metal ion coordination chemistry found in mussel adhesive proteins is developed. Deposited metal ions increase the local crosslinking density, which induces sharp bending of the hydrogel. Reversibly bound metal ions can be removed and reintroduced in a different pattern so that the hydrogel can be reprogrammed to transform into a different 3-dimentional shape.
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Affiliation(s)
- Bruce P Lee
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI, 49931, USA
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57
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Holten-Andersen N, Jaishankar A, Harrington M, Fullenkamp DE, DiMarco G, He L, McKinley GH, Messersmith PB, Lee KYC. Metal-coordination: Using one of nature's tricks to control soft material mechanics. J Mater Chem B 2014; 2:2467-2472. [PMID: 26413297 PMCID: PMC4582448 DOI: 10.1039/c3tb21374a] [Citation(s) in RCA: 153] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Growing evidence supports a critical role of dynamic metal-coordination crosslinking in soft biological material properties such as self-healing and underwater adhesion1. Using bio-inspired metal-coordinating polymers, initial efforts to mimic these properties have shown promise2. Here we demonstrate how bio-inspired aqueous polymer network mechanics can be easily controlled via metal-coordination crosslink dynamics; metal ion-based crosslink stability control allows aqueous polymer network relaxation times to be finely tuned over several orders of magnitude. In addition to further biological material insights, our demonstration of this compositional scaling mechanism should provide inspiration for new polymer material property-control designs.
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Affiliation(s)
- Niels Holten-Andersen
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Aditya Jaishankar
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Matthew Harrington
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany
| | - Dominic E. Fullenkamp
- Department of Biomedical Engineering and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA
| | - Genevieve DiMarco
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Lihong He
- Department of Biomedical Engineering and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA
| | - Gareth H. McKinley
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Phillip B. Messersmith
- Department of Biomedical Engineering and Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA
| | - Ka Yee C. Lee
- Department of Chemistry, Institute for Biophysical Dynamics, and the James Franck Institute, The University of Chicago, Chicago, IL 60637, USA
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58
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Gao J, Xing F, Bai Y, Zhu S. Synthesis, spectroscopy, and binding constants of ketocatechol-containing iminodiacetic acid and its Fe(iii), Cu(ii), and Zn(ii) complexes and reaction of Cu(ii) complex with H2O2 in aqueous solution. Dalton Trans 2014; 43:7964-78. [DOI: 10.1039/c4dt00118d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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59
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Fullenkamp DE, Barrett DG, Miller DR, Kurutz JW, Messersmith PB. pH-dependent cross-linking of catechols through oxidation via Fe 3+ and potential implications for mussel adhesion. RSC Adv 2014; 4:25127-25134. [PMID: 25243062 DOI: 10.1039/c4ra03178d] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The mussel byssus is a remarkable attachment structure that is formed by injection molding and rapid in-situ hardening of concentrated solutions of proteins enriched in the catecholic amino acid 3,4-dihydroxy-L-phenylalanine (DOPA). Fe3+, found in high concentrations in the byssus, has been speculated to participate in redox reactions with DOPA that lead to protein polymerization, however direct evidence to support this hypothesis has been lacking. Using small molecule catechols, DOPA-containing peptides, and native mussel foot proteins, we report the first direct observation of catechol oxidation and polymerization accompanied by reduction of Fe3+ to Fe2+. In the case of the small molecule catechol, we identified two dominant dimer species and characterized their connectivities by nuclear magnetic resonance (NMR), with the C6-C6 and C5-C6 linked species as the major and minor products, respectively. For the DOPA-containing peptide, we studied the pH dependence of the reaction and demonstrated that catechol polymerization occurs readily at low pH, but is increasingly diminished in favor of metal-catechol coordination interactions at higher pH. Finally, we demonstrate that Fe3+ can induce cross-links in native byssal mussel proteins mefp-1 and mcfp-1 at acidic pH. Based on these findings, we discuss the potential implications to the chemistry of mussel adhesion.
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Affiliation(s)
- Dominic E Fullenkamp
- Biomedical Engineering Department, Northwestern University, Evanston, IL 60208 ; Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208
| | - Devin G Barrett
- Biomedical Engineering Department, Northwestern University, Evanston, IL 60208 ; Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208 ; Institute for Bionanotechnology in Medicine, Northwestern University, Evanston, IL 60208
| | - Dusty R Miller
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, California 93106, USA
| | - Josh W Kurutz
- Integrated Molecular Structure Education and Research Center, Northwestern University, Evanston, IL 60208
| | - Phillip B Messersmith
- Biomedical Engineering Department, Northwestern University, Evanston, IL 60208 ; Materials Science and Engineering Department, Northwestern University, Evanston, IL 60208 ; Chemical and Biological Engineering Department, Northwestern University, Evanston, IL 60208 ; Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208 ; Institute for Bionanotechnology in Medicine, Northwestern University, Evanston, IL 60208 ; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Evanston, IL 60208
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60
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Wang X, Jiang Z, Shi J, Zhang C, Zhang W, Wu H. Dopamine-Modified Alginate Beads Reinforced by Cross-Linking via Titanium Coordination or Self-Polymerization and Its Application in Enzyme Immobilization. Ind Eng Chem Res 2013. [DOI: 10.1021/ie401239e] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Xiaoli Wang
- Key Laboratory
for Green Chemical Technology of Ministry of Education, School of
Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Zhongyi Jiang
- Key Laboratory
for Green Chemical Technology of Ministry of Education, School of
Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- National Key Laboratory
of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Jiafu Shi
- School of Environmental Science & Engineering, Tianjin University, Tianjin 300072, China
| | - Chunhong Zhang
- Key Laboratory
for Green Chemical Technology of Ministry of Education, School of
Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Wenyan Zhang
- Key Laboratory
for Green Chemical Technology of Ministry of Education, School of
Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Hong Wu
- Key Laboratory
for Green Chemical Technology of Ministry of Education, School of
Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
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61
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Morris G, Robertson I, Tatko CD. Iron binding β-hairpin peptides. Biometals 2013; 26:667-75. [DOI: 10.1007/s10534-013-9638-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Accepted: 05/26/2013] [Indexed: 10/26/2022]
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62
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Wang X, Jiang Z, Shi J, Liang Y, Zhang C, Wu H. Metal-organic coordination-enabled layer-by-layer self-assembly to prepare hybrid microcapsules for efficient enzyme immobilization. ACS APPLIED MATERIALS & INTERFACES 2012; 4:3476-3483. [PMID: 22724538 DOI: 10.1021/am300559j] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A novel layer-by-layer self-assembly approach enabled by metal-organic coordination was developed to prepare polymer-inorganic hybrid microcapsules. Alginate was first activated via N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxy succinimide (NHS) coupling chemistry, and subsequently reacted with dopamine. Afterward, the dopamine modified alginate (Alg-DA) and titanium(IV) bis(ammonium lactato) dihydroxide (Ti(IV)) were alternatively deposited onto CaCO3 templates. The coordination reaction between the catechol groups of Alg-DA and the Ti(IV) allowed the alternative assembly to form a series of multilayers. After removing the templates, the alginate-titanium hybrid microcapsules were obtained. The high mechanical stability of hybrid microcapsules was demonstrated by osmotic pressure experiment. Furthermore, the hybrid microcapsules displayed superior thermal stability due to Ti(IV) coordination. Catalase (CAT) was used as model enzyme, either encapsulated inside or covalently attached on the surface of the resultant microcapsules. No CAT leakage from the microcapsules was detected after incubation for 48 h. The encapsulated CAT, with a loading capacity of 450-500 mg g(-1) microcapsules, exhibited desirable long-term storage stability, whereas the covalently attached CAT, with a loading capacity of 100-150 mg g(-1) microcapsules, showed desirable operational stability.
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Affiliation(s)
- Xiaoli Wang
- Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University , Tianjin, P. R. China
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63
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Dehaen G, Eliseeva SV, Kimpe K, Laurent S, Vander Elst L, Muller RN, Dehaen W, Binnemans K, Parac-Vogt TN. A Self-Assembled Complex with a Titanium(IV) Catecholate Core as a Potential Bimodal Contrast Agent. Chemistry 2011; 18:293-302. [DOI: 10.1002/chem.201101413] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 08/23/2011] [Indexed: 11/06/2022]
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64
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Holten-Andersen N, Harrington MJ, Birkedal H, Lee BP, Messersmith PB, Lee KYC, Waite JH. pH-induced metal-ligand cross-links inspired by mussel yield self-healing polymer networks with near-covalent elastic moduli. Proc Natl Acad Sci U S A 2011; 108:2651-5. [PMID: 21278337 PMCID: PMC3041094 DOI: 10.1073/pnas.1015862108] [Citation(s) in RCA: 928] [Impact Index Per Article: 71.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Growing evidence supports a critical role of metal-ligand coordination in many attributes of biological materials including adhesion, self-assembly, toughness, and hardness without mineralization [Rubin DJ, Miserez A, Waite JH (2010) Advances in Insect Physiology: Insect Integument and Color, eds Jérôme C, Stephen JS (Academic Press, London), pp 75-133]. Coordination between Fe and catechol ligands has recently been correlated to the hardness and high extensibility of the cuticle of mussel byssal threads and proposed to endow self-healing properties [Harrington MJ, Masic A, Holten-Andersen N, Waite JH, Fratzl P (2010) Science 328:216-220]. Inspired by the pH jump experienced by proteins during maturation of a mussel byssus secretion, we have developed a simple method to control catechol-Fe(3+) interpolymer cross-linking via pH. The resonance Raman signature of catechol-Fe(3+) cross-linked polymer gels at high pH was similar to that from native mussel thread cuticle and the gels displayed elastic moduli (G') that approach covalently cross-linked gels as well as self-healing properties.
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Affiliation(s)
- Niels Holten-Andersen
- Department of Chemistry, Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA.
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65
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Doraiswamy A, Dunaway TM, Wilker JJ, Narayan RJ. Inkjet printing of bioadhesives. J Biomed Mater Res B Appl Biomater 2009; 89:28-35. [PMID: 18712812 DOI: 10.1002/jbm.b.31183] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Over the past century, synthetic adhesives have largely displaced their natural counterparts in medical applications. However, rising concerns over the environmental and toxicological effects of the solvents, monomers, and additives used in synthetic adhesives have recently led the scientific community to seek natural substitutes. Marine mussel adhesive protein is a formaldehyde-free natural adhesive that demonstrates excellent adhesion to several classes of materials, including glasses, metals, metal oxides, and polymers. In this study, we have demonstrated computer aided design (CAD) patterning of various biological adhesives using piezoelectric inkjet technology. A MEMS-based piezoelectric actuator was used to control the flow of the mussel adhesive protein solution through the ink jet nozzles. Fourier transform infrared spectroscopy (FTIR), microscopy, and adhesion studies were performed to examine the chemical, structural, and functional properties of these patterns, respectively. FTIR revealed the piezoelectric inkjet technology technique to be nondestructive. Atomic force microscopy was used to determine the extent of chelation caused by Fe(III). The adhesive strength in these materials was correlated with the extent of chelation by Fe(III). Piezoelectric inkjet printing of naturally-derived biological adhesives may overcome several problems associated with conventional tissue bonding materials. This technique may significantly improve wound repair in next generation eye repair, fracture fixation, wound closure, and drug delivery devices.
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Affiliation(s)
- Anand Doraiswamy
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7575, USA
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66
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Contreras D, Rodríguez J, Freer J, Schwederski B, Kaim W. Enhanced hydroxyl radical production by dihydroxybenzene-driven Fenton reactions: implications for wood biodegradation. J Biol Inorg Chem 2007; 12:1055-61. [PMID: 17636352 DOI: 10.1007/s00775-007-0274-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Accepted: 06/28/2007] [Indexed: 11/25/2022]
Abstract
Brown rot fungi degrade wood, in initial stages, mainly through hydroxyl radicals (.OH) produced by Fenton reactions. These Fenton reactions can be promoted by dihydroxybenzenes (DHBs), which can chelate and reduce Fe(III), increasing the reactivity for different substrates. This mechanism allows the extensive degradation of carbohydrates and the oxidation of lignin during wood biodegradation by brown rot fungi. To understand the enhanced reactivity in these systems, kinetics experiments were carried out, measuring .OH formation by the spin-trapping technique of electron paramagnetic resonance spectroscopy. As models of the fungal DHBs, 1,2-dihydroxybenzene (catechol), 2,3-dihydroxybenzoic acid and 3,4-dihydroxybenzoic acid were utilized as well as 1,2-dihydroxy-3,5-benzenedisulfonate as a non-Fe(III)-reducing substance for comparison. Higher amounts and maintained concentrations of .OH were observed in the driven Fenton reactions versus the unmodified Fenton process. A linear correlation between the logarithms of complex stability constants and the .OH production was observed, suggesting participation of such complexes in the radical production.
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Affiliation(s)
- David Contreras
- Faculty of Chemical Sciences, University of Concepción, Casilla 160-C, Concepción, Chile.
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67
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Loizou E, Weisser JT, Dundigalla A, Porcar L, Schmidt G, Wilker JJ. Structural Effects of Crosslinking a Biopolymer Hydrogel Derived from Marine Mussel Adhesive Protein. Macromol Biosci 2006; 6:711-8. [PMID: 16967473 DOI: 10.1002/mabi.200600097] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In an effort to explore new biocompatible substrates for biomedical technologies, we present a structural study on a crosslinked gelatinous protein extracted from marine mussels. Prior studies have shown the importance of iron in protein crosslinking and mussel adhesive formation. Here, the structure and properties of an extracted material were examined both before and after crosslinking with iron. The structures of these protein hydrogels were studied by SEM, SANS, and SAXS. Viscoelasticity was tested by rheological means. The starting gel was found to have a heterogeneous porous structure on a micrometer scale and, surprisingly, a regular structure on the micron to nanometer scale. However disorder, or "no periodic structure", was deduced from scattering on nanometer length scales at very high q. Crosslinking with iron condensed the structure on a micrometer level. On nanometer length scales at high q, small angle neutron scattering showed no significant differences between the samples, possibly due to strong heterogeneity. X-ray scattering also confirmed the absence of any defined periodic structure. Partial crosslinking transformed the viscoelastic starting gel into one with more rigid and elastic properties.
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Affiliation(s)
- Elena Loizou
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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