1
|
Upadhya R, Di Mare E, Tamasi MJ, Kosuri S, Murthy NS, Gormley AJ. Examining polymer-protein biophysical interactions with small-angle x-ray scattering and quartz crystal microbalance with dissipation. J Biomed Mater Res A 2023; 111:440-450. [PMID: 36537182 PMCID: PMC9908847 DOI: 10.1002/jbm.a.37479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/29/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022]
Abstract
Polymer-protein hybrids can be deployed to improve protein solubility and stability in denaturing environments. While previous work used robotics and active machine learning to inform new designs, further biophysical information is required to ascertain structure-function behavior. Here, we show the value of tandem small-angle x-ray scattering (SAXS) and quartz crystal microbalance with dissipation (QCMD) experiments to reveal detailed polymer-protein interactions with horseradish peroxidase (HRP) as a test case. Of particular interest was the process of polymer-protein complex formation under thermal stress whereby SAXS monitors formation in solution while QCMD follows these dynamics at an interface. The radius of gyration (Rg ) of the protein as measured by SAXS does not change significantly in the presence of polymer under denaturing conditions, but thickness and dissipation changes were observed in QCMD data. SAXS data with and without thermal stress were utilized to create bead models of the potential complexes and denatured enzyme, and each model fit provided insight into the degree of interactions. Additionally, QCMD data demonstrated that HRP deforms by spreading upon surface adsorption at low concentration as shown by longer adsorption times and smaller frequency shifts. In contrast, thermally stressed and highly inactive HRP had faster adsorption kinetics. The combination of SAXS and QCMD serves as a framework for biophysical characterization of interactions between proteins and polymers which could be useful in designing polymer-protein hybrids.
Collapse
Affiliation(s)
- Rahul Upadhya
- Department of Biomedical Engineering, RutgersThe State University of New JerseyPiscatawayNew JerseyUSA
| | - Elena Di Mare
- Department of Biomedical Engineering, RutgersThe State University of New JerseyPiscatawayNew JerseyUSA
| | - Matthew J. Tamasi
- Department of Biomedical Engineering, RutgersThe State University of New JerseyPiscatawayNew JerseyUSA
| | - Shashank Kosuri
- Department of Biomedical Engineering, RutgersThe State University of New JerseyPiscatawayNew JerseyUSA
| | - N. Sanjeeva Murthy
- Department of Biomedical Engineering, RutgersThe State University of New JerseyPiscatawayNew JerseyUSA
| | - Adam J. Gormley
- Department of Biomedical Engineering, RutgersThe State University of New JerseyPiscatawayNew JerseyUSA
| |
Collapse
|
2
|
Tamasi MJ, Patel RA, Borca CH, Kosuri S, Mugnier H, Upadhya R, Murthy NS, Webb MA, Gormley AJ. Machine Learning on a Robotic Platform for the Design of Polymer-Protein Hybrids. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2201809. [PMID: 35593444 PMCID: PMC9339531 DOI: 10.1002/adma.202201809] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/26/2022] [Indexed: 06/04/2023]
Abstract
Polymer-protein hybrids are intriguing materials that can bolster protein stability in non-native environments, thereby enhancing their utility in diverse medicinal, commercial, and industrial applications. One stabilization strategy involves designing synthetic random copolymers with compositions attuned to the protein surface, but rational design is complicated by the vast chemical and composition space. Here, a strategy is reported to design protein-stabilizing copolymers based on active machine learning, facilitated by automated material synthesis and characterization platforms. The versatility and robustness of the approach is demonstrated by the successful identification of copolymers that preserve, or even enhance, the activity of three chemically distinct enzymes following exposure to thermal denaturing conditions. Although systematic screening results in mixed success, active learning appropriately identifies unique and effective copolymer chemistries for the stabilization of each enzyme. Overall, this work broadens the capabilities to design fit-for-purpose synthetic copolymers that promote or otherwise manipulate protein activity, with extensions toward the design of robust polymer-protein hybrid materials.
Collapse
Affiliation(s)
- Matthew J Tamasi
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Roshan A Patel
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Carlos H Borca
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Shashank Kosuri
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Heloise Mugnier
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Rahul Upadhya
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - N Sanjeeva Murthy
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| | - Michael A Webb
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Adam J Gormley
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
| |
Collapse
|
3
|
Plikusiene I, Maciulis V, Ramanavicius A, Ramanaviciene A. Spectroscopic Ellipsometry and Quartz Crystal Microbalance with Dissipation for the Assessment of Polymer Layers and for the Application in Biosensing. Polymers (Basel) 2022; 14:polym14051056. [PMID: 35267879 PMCID: PMC8915094 DOI: 10.3390/polym14051056] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 02/24/2022] [Accepted: 02/28/2022] [Indexed: 01/07/2023] Open
Abstract
Polymers represent materials that are applied in almost all areas of modern life, therefore, the characterization of polymer layers using different methods is of great importance. In this review, the main attention is dedicated to the non-invasive and label-free optical and acoustic methods, namely spectroscopic ellipsometry (SE) and quartz crystal microbalance with dissipation (QCM-D). The specific advantages of these techniques applied for in situ monitoring of polymer layer formation and characterization, biomolecule immobilization, and registration of specific interactions were summarized and discussed. In addition, the exceptional benefits and future perspectives of combined spectroscopic ellipsometry and QCM-D (SE/QCM-D) in one measurement are overviewed. Recent advances in the discussed area allow us to conclude that especially significant breakthroughs are foreseen in the complementary application of both QCM-D and SE techniques for the investigation of polymer structure and assessment of the interaction between biomolecules such as antigens and antibodies, receptors and ligands, and complementary DNA strands.
Collapse
Affiliation(s)
- Ieva Plikusiene
- Nanotechnas–Center of Nanotechnology and Materials Science, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT-03225 Vilnius, Lithuania; (V.M.); (A.R.)
- State Research Institute Centre for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania
- Correspondence: (I.P.); (A.R.)
| | - Vincentas Maciulis
- Nanotechnas–Center of Nanotechnology and Materials Science, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT-03225 Vilnius, Lithuania; (V.M.); (A.R.)
- State Research Institute Centre for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania
| | - Arunas Ramanavicius
- Nanotechnas–Center of Nanotechnology and Materials Science, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT-03225 Vilnius, Lithuania; (V.M.); (A.R.)
- State Research Institute Centre for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania
| | - Almira Ramanaviciene
- Nanotechnas–Center of Nanotechnology and Materials Science, Faculty of Chemistry and Geosciences, Vilnius University, Naugarduko Str. 24, LT-03225 Vilnius, Lithuania; (V.M.); (A.R.)
- Department of Immunology, State Research Institute Centre for Innovative Medicine, Santariskiu g. 5, LT-08406 Vilnius, Lithuania
- Correspondence: (I.P.); (A.R.)
| |
Collapse
|
4
|
Koçoğlu İO, Erden PE, Kılıç E. Disposable biogenic amine biosensors for histamine determination in fish. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:3802-3812. [PMID: 32760948 DOI: 10.1039/d0ay00802h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This study presents the development of disposable biosensors employed in the determination of histamine in fish samples. Screen printed carbon electrodes (SPCEs) were first modified with a mixture of titanium dioxide nanoparticles (TiO2), carboxylated multiwalled carbon nanotubes (c-MWCNTs), hexaammineruthenium(iii) chloride (RU) and chitosan (CS). Diamine oxidase (DAO) or monoamine oxidase (MAO) enzymes were further immobilized onto the TiO2-c-MWCNT-RU-CS/SPCEs via 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride (EDC) and hydroxysuccinimide (NHS) chemistry for the fabrication of the biosensors. The morphological and electrochemical properties of the proposed biosensors were studied using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, cyclic voltammetry (CV), chronoamperometry and electrochemical impedance spectroscopy (EIS). A performance comparison of two biosensors indicated that the one based on DAO had a linear concentration range from 9.9 × 10-6 to 1.1 × 10-3 M and the other based on MAO, from 5.6 × 10-5 to 1.1 × 10-3 M for histamine. The sensitivity of the DAO based biosensor was almost 1.5 times higher than that of the MAO based biosensor. The proposed biosensors were successfully employed to determine histamine in fish samples and the recoveries were between 100.0% and 104.6%.
Collapse
Affiliation(s)
- İrem Okman Koçoğlu
- Department of Chemistry, Faculty of Science, Ankara University, 06100, Ankara, Turkey.
| | | | | |
Collapse
|
5
|
Enhancement of hemostatic property of plant derived oxidized nanocellulose-silk fibroin based scaffolds by thrombin loading. Carbohydr Polym 2018; 208:168-179. [PMID: 30658788 DOI: 10.1016/j.carbpol.2018.12.056] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 11/15/2018] [Accepted: 12/18/2018] [Indexed: 01/04/2023]
Abstract
To combat post-surgical and traumatic bleeding conditions effective hemostasis is of great importance. The study was designed to investigate the effect of thrombin (Th) loading on hemostatic performance of TEMPO-oxidized cellulose nanofiber (TOCN)-silk fibroin (SF) scaffolds. Addition of SF with TOCN significantly (***P < 0.001) increased blood absorption capacity and improved biocompatibility of TOCN. Thrombin loading potentiated platelet activation and hemostatic property of scaffolds (TOCN-SF-Th) compared to samples without thrombin (TOCN-SF). The hemostatic time of TOCN-SF5-Th in rabbit ear artery bleeding model was reduced (*** P < 0.001) to 114 s from 220 s of TOCN-SF5. Reduction in bleeding time and blood loss of TOCN-SF5-Th in rat tail amputation and liver avulsion model was comparable to commercial hemostat (Floseal). Surface morphology (SEM) of samples applied on bleeding site showed that RBCs and fibrin fiber could strongly interact with TOCN-SF and TOCN-SF-Th scaffolds. The result suggests that TOCN-SF-Th can be a promising candidate for designing hemostatic agents.
Collapse
|
6
|
Biosensor-Based Approaches for Detecting Ochratoxin A and 2,4,6-Trichloroanisole in Beverages. BEVERAGES 2018. [DOI: 10.3390/beverages4010024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
7
|
Development of a QCM-D biosensor for Ochratoxin A detection in red wine. Talanta 2017; 166:193-197. [PMID: 28213222 DOI: 10.1016/j.talanta.2017.01.054] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 01/13/2017] [Accepted: 01/18/2017] [Indexed: 01/27/2023]
Abstract
Ochratoxin A (OTA), a highly toxic compound, is one of the most widely spread mycotoxins that contaminates a large variety of agricultural commodities. Due to its presence in the food chain, it imposes a hazard on both human and animal health. Therefore, there is a need for precise, fast and simple methods for toxin quantification. Herein, a novel sensor based on a quartz crystal microbalance with dissipation monitoring (QCM-D) and antibodies for specific analyte recognition was developed for rapid and sensitive detection of OTA in red wine. The combination of indirect competitive assay with QCM-D gives a straightforward device, which can simultaneously measure frequency (Δf) and dissipation (ΔD) changes resulting in detailed information about the mass attached to the sensor surface as well as conformational changes, viscoelastic properties and the hydration state of the film. Small molecules (such as OTA) suffer from poor LOD due to the high concentration of primary antibody needed to generate adequate signal. In the present study, amplification of the QCM-D signal was obtained by applying secondary antibodies conjugated with gold nanoparticles (AuNPs). Thanks to this, a linear detection range of 0.2-40ngmL-1 has been achieved with an excellent LOD of 0.16ngmL-1, which is one order of magnitude lower than LOD specified by European Union legislation concerning the limit of OTA in food. Moreover, a matrix effect (caused by the occurrence of polyphenols in wine) and associated non-specific interactions with the sensor surface was completely eliminated by a simple pre-treatment of the wine with the addition of 3% poly(vinylpyrrolidone) (PVP).
Collapse
|
8
|
Wang W, Zhou W, Wei W, Li J, Hao D, Su Z, Ma G. Towards A Deeper Understanding of the Interfacial Adsorption of Enzyme Molecules in Gigaporous Polymeric Microspheres. Polymers (Basel) 2016; 8:polym8040116. [PMID: 30979221 PMCID: PMC6431888 DOI: 10.3390/polym8040116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 03/06/2016] [Accepted: 03/24/2016] [Indexed: 11/21/2022] Open
Abstract
Compared with the one immobilized in the conventional mesoporous microspheres, the enzyme immobilized in gigaporous microspheres showed much higher activity and better stability. To gain a deeper understanding, we herein selected lipase as a prototype to comparatively analyze the adsorption behavior of lipase at interfaces in gigaporous and mesoporous polystyrene microspheres at very low lipase concentration, and further compared with the adsorption on a completely flat surface (a chip). Owing to the limited space of narrow pores, lipase molecules were inclined to be adsorbed as a monolayer in mesoporous microspheres. During this process, the interaction between lipase molecules and the interface was stronger, which could result in the structural change of lipase molecular and compromised specific activity. In addition to monolayer adsorption, more multilayer adsorption of enzyme molecules also occurred in gigaporous microspheres. Besides the adsorption state, the pore curvature also affected the lipase adsorption. Due to the multilayer adsorption, the excellent mass transfer properties for the substrate and the product in the large pores, and the small pore curvature, lipase immobilized in gigaporous microspheres showed better behaviors.
Collapse
Affiliation(s)
- Weichen Wang
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Weiqing Zhou
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Wei Wei
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Juan Li
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Dongxia Hao
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Zhiguo Su
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Guanghui Ma
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| |
Collapse
|
9
|
|
10
|
Misra N, Kumar V, Goel NK, Varshney L. Laccase immobilization on radiation synthesized epoxy functionalized polyethersulfone beads and their application for degradation of acid dye. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.09.035] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
11
|
Che HX, Yeap SP, Osman MS, Ahmad AL, Lim J. Directed assembly of bifunctional silica-iron oxide nanocomposite with open shell structure. ACS APPLIED MATERIALS & INTERFACES 2014; 6:16508-16518. [PMID: 25198872 DOI: 10.1021/am5050949] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The synthesis of nanocomposite with controlled surface morphology plays a key role for pollutant removal from aqueous environments. The influence of the molecular size of the polyelectrolyte in synthesizing silica-iron oxide core-shell nanocomposite with open shell structure was investigated by using dynamic light scattering, atomic force microscopy, and quartz crystal microbalance with dissipation (QCM-D). Here, poly(diallydimethylammonium chloride) (PDDA) was used to promote the attachment of iron oxide nanoparticles (IONPs) onto the silica surface to assemble a nanocomposite with magnetic and catalytic bifunctionality. High molecular weight PDDA tended to adsorb on silica colloid, forming a more extended conformation layer than low molecular weight PDDA. Subsequent attachment of IONPs onto this extended PDDA layer was more randomly distributed, forming isolated islands with open space between them. By taking amoxicillin, an antibiotic commonly found in pharmaceutical waste, as the model system, better removal was observed for silica-iron oxide nanocomposite with a more extended open shell structure.
Collapse
Affiliation(s)
- Hui Xin Che
- School of Chemical Engineering, Universiti Sains Malaysia , 14300 Nibong Tebal, Penang, Malaysia
| | | | | | | | | |
Collapse
|
12
|
Song J, Krause WE, Rojas OJ. Adsorption of polyalkyl glycol ethers and triblock nonionic polymers on PET. J Colloid Interface Sci 2014; 420:174-81. [DOI: 10.1016/j.jcis.2014.01.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 12/21/2013] [Accepted: 01/09/2014] [Indexed: 11/17/2022]
|
13
|
Jin J, Jiang W, Yin J, Ji X, Stagnaro P. Plasma proteins adsorption mechanism on polyethylene-grafted poly(ethylene glycol) surface by quartz crystal microbalance with dissipation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:6624-6633. [PMID: 23659226 DOI: 10.1021/la4017239] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Protein adsorption has a vital role in biomaterial surface science because it is directly related to the hemocompatibility of blood-contacting materials. In this study, monomethoxy poly(ethylene glycol) (mPEG) with two different molecular weights was grafted on polyethylene as a model to elucidate the adsorption mechanisms of plasma protein through quartz crystal microbalance with dissipation (QCM-D). Combined with data from platelet adhesion, whole blood clotting time, and hemolysis rate, the blood compatibility of PE-g-mPEG film was found to have significantly improved. Two adsorption schemes were developed for real-time monitoring of protein adsorption. Results showed that the preadsorbed bovine serum albumin (BSA) on the surfaces of PE-g-mPEG films could effectively inhibit subsequent adsorption of fibrinogen (Fib). Nonspecific protein adsorption of BSA was determined by surface coverage, not by the chain length of PEG. Dense PEG brush could release more trapped water molecules to resist BSA adsorption. Moreover, the preadsorbed Fib could be gradually displaced by high-concentration BSA. However, the adsorption and displacement of Fib was determined by surface hydrophilicity.
Collapse
Affiliation(s)
- Jing Jin
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China
| | | | | | | | | |
Collapse
|
14
|
Oh JH, Lee JS, Park KM, Moon HT, Park KD. Tyrosinase-mediated surface grafting of cell adhesion peptide onto micro-fibrous polyurethane for improved endothelialization. Macromol Res 2012. [DOI: 10.1007/s13233-012-0161-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
15
|
Rivera JG, Messersmith PB. Polydopamine-assisted immobilization of trypsin onto monolithic structures for protein digestion. J Sep Sci 2012; 35:1514-20. [DOI: 10.1002/jssc.201200073] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- José G. Rivera
- Biomedical Engineering Department; Northwestern University; Evanston IL USA
- Chemistry of Life Processes Institute; Northwestern University; Evanston IL USA
| | - Phillip B. Messersmith
- Biomedical Engineering Department; Northwestern University; Evanston IL USA
- Materials Science and Engineering Department; Northwestern University; Evanston IL USA
- Chemical and Biological Engineering Department; Northwestern University; Evanston IL USA
- Chemistry of Life Processes Institute; Northwestern University; Evanston IL USA
- Institute for Bionanotechnology in Medicine; Northwestern University; Chicago IL USA. Robert H. Lurie Comprehensive Cancer Center; Northwestern University; Chicago IL USA
| |
Collapse
|
16
|
Liu X, Vesterinen AH, Genzer J, Seppälä JV, Rojas OJ. Adsorption of PEO-PPO-PEO triblock copolymers with end-capped cationic chains of poly(2-dimethylaminoethyl methacrylate). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:9769-9780. [PMID: 21721578 DOI: 10.1021/la201596x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We study the adsorption of a symmetric triblock copolymer of ethylene oxide, EO, and propylene oxide, PO, end-capped with quarternized poly(2-dimethylaminoethyl methacrylate), DMAEMA (DMAEMA(24)-EO(132)PO(50)EO(132)-DMAEMA(24)). Light scattering and tensiometry are used to measure the relative size of the associated structures and surface excess at the air-liquid interface. The adsorbed amount, the amount of coupled water, and the viscoelasticity of the adsorbed polymer layer are measured on hydrophobic and hydrophilic surfaces (polypropylene, cellulose, and silica) by using quartz crystal microgravimetry (QCM) and surface plasmon resonance (SPR) at different ionic strengths and temperatures. The results of the experiments are compared with those obtained after adsorption of the uncharged precursor copolymer, without the cationic end-caps (EO(132)PO(50)EO(132)). DMAEMA(24)-EO(132)PO(50)EO(132)-DMAEMA(24) possesses higher affinity with the negatively charged silica and cellulose surfaces while the uncharged copolymer adsorbs to a larger extent on polypropylene surfaces. In this latter case, adsorption increases with increasing solution ionic strength and temperature. Adsorption of EO(132)PO(50)EO(132) on silica surfaces has little effect on the water contact angle (WCA), while adsorption of DMAEMA(24)-EO(132)PO(50)EO(132)-DMAEMA(24) increases the WCA of silica to 32°, indicating a large density of exposed PPO blocks upon adsorption. After adsorption of EO(132)PO(50)EO(132) and DMAEMA(24)-EO(132)PO(50)EO(132)-DMAEMA(24) on PP, the WCA is reduced by ≈14° and ≈28°, respectively, due to the exposed hydrophilic EO and highly water-soluble DMAEMA segments on the surfaces. The extent of surface coverage at saturation at the polypropylene/liquid interfaces (≈31 and 40 nm(2)/molecule obtained by QCM and SPR, respectively) is much lower, as expected, when compared with results obtained at the air/liquid interface, where a tighter packing is observed. The percentage of water coupled to the adsorbed cationic polymer decreases with solution ionic strength. Overall, these observations are ascribed to the effects of electrostatic screening, polymer hydrodynamic size, and solvency.
Collapse
Affiliation(s)
- Xiaomeng Liu
- Department of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina 27695, United States
| | | | | | | | | |
Collapse
|
17
|
Ali M, Ramirez P, Tahir MN, Mafe S, Siwy Z, Neumann R, Tremel W, Ensinger W. Biomolecular conjugation inside synthetic polymer nanopores via glycoprotein-lectin interactions. NANOSCALE 2011; 3:1894-1903. [PMID: 21423941 DOI: 10.1039/c1nr00003a] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We demonstrate the supramolecular bioconjugation of concanavalin A (Con A) protein with glycoenzyme horseradish peroxidase (HRP) inside single nanopores, fabricated in heavy ion tracked polymer membranes. Firstly, the HRP-enzyme was covalently immobilized on the inner wall of the pores using carbodiimide coupling chemistry. The immobilized HRP-enzyme molecules bear sugar (mannose) groups available for the binding of Con A protein. Secondly, the bioconjugation of Con A on the pore wall was achieved through its biospecific interactions with the mannose residues of the HRP enzyme. The immobilization of biomolecules inside the nanopore leads to the reduction of the available area for ionic transport, and this blocking effect can be exploited to tune the conductance and selectivity of the nanopore in aqueous solution. Both cylindrical and conical nanopores were used in the experiments. The possibility of obtaining two or more conductance states (output), dictated by the degree of nanopore blocking resulted from the different biomolecules in solution (input), as well as the current rectification properties obtained with the conical nanopore, could also allow implementing information processing at the nanometre scale. Model simulations based on the transport equations further verify the feasibility of the sensing procedure that involves concepts from supramolecular chemistry, molecular imprinting, recognition, and nanotechnology.
Collapse
Affiliation(s)
- Mubarak Ali
- Technische Universität Darmstadt, Fachbereich Material-u. Geowissenschaften, Fachgebiet Materialanalytik, Petersenstraβe 23, D-64287, Darmstadt, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Liu X, Wu D, Turgman-Cohen S, Genzer J, Theyson TW, Rojas OJ. Adsorption of a nonionic symmetric triblock copolymer on surfaces with different hydrophobicity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:9565-9574. [PMID: 20355719 DOI: 10.1021/la100156a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This study investigates the adsorption of a symmetric triblock nonionic polymer comprising ethylene oxide (EO) and propylene oxide (PO) blocks (Pluronic P-105, EO(37)PO(56)EO(37)) on a range of substrates including hydrophobic, i.e., polypropylene (PP), poly(ethylene terephthalate) (PET), nylon, and graphite, and hydrophilic, i.e., cellulose and silica. The adsorption process and the structure of the hydrated adsorbed layers are followed by quartz crystal microgravimetry (QCM), surface plasmon resonance (SPR), and atomic force microscopy. The unhydrated surfaces are characterized by ellipsometry and contact angle techniques. The adsorption kinetics and the extent of adsorption are determined by monitoring the changes in resonance frequency and refractive index of sensors coated with ultrathin films of the various substrates. Langmuirian-type adsorption kinetics is observed in all cases studied. The amount of adsorbed Pluronic on hydrophobic polymer surfaces (PP, PET, and nylon) exceeds that on the hydrophilic cellulose. The hydrophobic (graphite) mineral surface adsorbs relatively low polymer mass, typical of a monolayer, while micellar structures are observed on the hydrophilic silica surface. The amount of water coupled to the adsorbed polymer layers is quantified by combining data from QCM, and SPR are found to increase with increasing polarity of the substrate. On the basis of contact angle data, the nonhydrated adsorbed structures produce modest increases in hydrophilicity of all the substrates investigated. Overall, insights are provided into the structure and stability of both hydrated and nonhydrated adsorbed triblock copolymer.
Collapse
Affiliation(s)
- Xiaomeng Liu
- Department of Forest Biomaterials, North Carolina State University, Raleigh, Raleigh, North Carolina 27695, USA
| | | | | | | | | | | |
Collapse
|
19
|
Song J, Yamagushi T, Silva DJ, Hubbe MA, Rojas OJ. Effect of Charge Asymmetry on Adsorption and Phase Separation of Polyampholytes on Silica and Cellulose Surfaces. J Phys Chem B 2009; 114:719-27. [DOI: 10.1021/jp909047t] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Junlong Song
- Department of Forest Biomaterials, North Carolina State University, Campus Box 8005, Raleigh, North Carolina 27695-8005, Nippon Paper Industries Co., Ltd., 1-2-2, Hitotsubashi, Chiyoda-ku, Tokyo 100-0003, Japan, Department of Chemical Engineering, Polytechnic School of São Paulo University, SP, Brazil, and Department of Forest Products Technology, Faculty of Chemistry and Materials Sciences, Helsinki University of Technology, P.O. Box 3320, FIN-02015 TKK, Espoo, Finland
| | - Takashi Yamagushi
- Department of Forest Biomaterials, North Carolina State University, Campus Box 8005, Raleigh, North Carolina 27695-8005, Nippon Paper Industries Co., Ltd., 1-2-2, Hitotsubashi, Chiyoda-ku, Tokyo 100-0003, Japan, Department of Chemical Engineering, Polytechnic School of São Paulo University, SP, Brazil, and Department of Forest Products Technology, Faculty of Chemistry and Materials Sciences, Helsinki University of Technology, P.O. Box 3320, FIN-02015 TKK, Espoo, Finland
| | - Deusanilde J. Silva
- Department of Forest Biomaterials, North Carolina State University, Campus Box 8005, Raleigh, North Carolina 27695-8005, Nippon Paper Industries Co., Ltd., 1-2-2, Hitotsubashi, Chiyoda-ku, Tokyo 100-0003, Japan, Department of Chemical Engineering, Polytechnic School of São Paulo University, SP, Brazil, and Department of Forest Products Technology, Faculty of Chemistry and Materials Sciences, Helsinki University of Technology, P.O. Box 3320, FIN-02015 TKK, Espoo, Finland
| | - Martin A. Hubbe
- Department of Forest Biomaterials, North Carolina State University, Campus Box 8005, Raleigh, North Carolina 27695-8005, Nippon Paper Industries Co., Ltd., 1-2-2, Hitotsubashi, Chiyoda-ku, Tokyo 100-0003, Japan, Department of Chemical Engineering, Polytechnic School of São Paulo University, SP, Brazil, and Department of Forest Products Technology, Faculty of Chemistry and Materials Sciences, Helsinki University of Technology, P.O. Box 3320, FIN-02015 TKK, Espoo, Finland
| | - Orlando J. Rojas
- Department of Forest Biomaterials, North Carolina State University, Campus Box 8005, Raleigh, North Carolina 27695-8005, Nippon Paper Industries Co., Ltd., 1-2-2, Hitotsubashi, Chiyoda-ku, Tokyo 100-0003, Japan, Department of Chemical Engineering, Polytechnic School of São Paulo University, SP, Brazil, and Department of Forest Products Technology, Faculty of Chemistry and Materials Sciences, Helsinki University of Technology, P.O. Box 3320, FIN-02015 TKK, Espoo, Finland
| |
Collapse
|
20
|
Wisitsoraat A, Karuwan C, Wong-Ek K, Phokharatkul D, Sritongkham P, Tuantranont A. High sensitivity electrochemical cholesterol sensor utilizing a vertically aligned carbon nanotube electrode with electropolymerized enzyme immobilization. SENSORS 2009; 9:8658-68. [PMID: 22291529 PMCID: PMC3260606 DOI: 10.3390/s91108658] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 09/30/2009] [Accepted: 10/10/2009] [Indexed: 11/16/2022]
Abstract
In this report, a new cholesterol sensor is developed based on a vertically aligned CNT electrode with two-step electrochemical polymerized enzyme immobilization. Vertically aligned CNTs are selectively grown on a 1 mm(2) window of gold coated SiO(2)/Si substrate by thermal chemical vapor deposition (CVD) with gravity effect and water-assisted etching. CNTs are then simultaneously functionalized and enzyme immobilized by electrochemical polymerization of polyaniline and cholesterol enzymes. Subsequently, ineffective enzymes are removed and new enzymes are electrochemically recharged. Scanning electron microscopic characterization indicates polymer-enzyme nanoparticle coating on CNT surface. Cyclic voltammogram (CV) measurements in cholesterol solution show the oxidation and reduction peaks centered around 450 and -220 mV, respectively. An approximately linear relationship between the cholesterol concentration and the response current could be observed in the concentration range of 50-300 mg/dl with a sensitivity of approximately 0.22 μA/mg·dl(-1), which is considerably higher compared to previously reported CNT bioprobe. In addition, good specificity toward glucose, uric acid acetaminophen and ascorbic acid have been obtained. Moreover, sensors have satisfactory stability, repeatability and life time. Therefore, the electropolymerized CNT bioprobe is promising for cholesterol detection in normal cholesterol concentration in human blood.
Collapse
Affiliation(s)
- Anurat Wisitsoraat
- Nanoelectronics and MEMS Laboratory, National Electronics and Computer Technology Center, 112 Thailand Science Park, Pahol Yothin Rd., Klong Luang, Pathumthani 12120, Thailand; E-Mails: (C.K.); (K.W.); (D.P.); (P.S.); (A.T.)
| | | | | | | | | | | |
Collapse
|
21
|
Volden S, Zhu K, Nyström B, Glomm WR. Use of cellulose derivatives on gold surfaces for reduced nonspecific adsorption of immunoglobulin G. Colloids Surf B Biointerfaces 2009; 72:266-71. [DOI: 10.1016/j.colsurfb.2009.04.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 04/01/2009] [Accepted: 04/16/2009] [Indexed: 11/30/2022]
|
22
|
Volden S, Moen AR, Glomm WR, Anthonsen T, Sjöblom J. Immobilization of Lipases fromCandida antarctica. Influence of Surface Polarity on Adsorption and Transesterification Activity. J DISPER SCI TECHNOL 2009. [DOI: 10.1080/01932690802644053] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
23
|
Gopalan AI, Lee KP, Ragupathy D. Development of a stable cholesterol biosensor based on multi-walled carbon nanotubes–gold nanoparticles composite covered with a layer of chitosan–room-temperature ionic liquid network. Biosens Bioelectron 2009; 24:2211-7. [DOI: 10.1016/j.bios.2008.11.034] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 11/06/2008] [Accepted: 11/27/2008] [Indexed: 02/07/2023]
|
24
|
Yang Y, Zhu Y, Chen Q, Liu Y, Zeng Y, Xu F. Carbon-nanotube-activated Pt quartz-crystal microbalance for the immunoassay of human IgG. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:351-355. [PMID: 19148888 DOI: 10.1002/smll.200801043] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Affiliation(s)
- Yu Yang
- Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai, PR China
| | | | | | | | | | | |
Collapse
|
25
|
Lee H, Rho J, Messersmith PB. Facile Conjugation of Biomolecules onto Surfaces via Mussel Adhesive Protein Inspired Coatings. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2009; 21:431-434. [PMID: 19802352 PMCID: PMC2755254 DOI: 10.1002/adma.200801222] [Citation(s) in RCA: 1026] [Impact Index Per Article: 68.4] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Affiliation(s)
- Haeshin Lee
- Biomedical Engineering Department, Northwestern University, 2145 Sheridan Rd. Evanston, IL 60208 (USA)
| | | | | |
Collapse
|
26
|
Amirkhani M, Volden S, Zhu K, Glomm WR, Nyström B. Adsorption of cellulose derivatives on flat gold surfaces and on spherical gold particles. J Colloid Interface Sci 2008; 328:20-8. [DOI: 10.1016/j.jcis.2008.09.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 09/01/2008] [Accepted: 09/05/2008] [Indexed: 10/21/2022]
|
27
|
Otzen D. Differential adsorption of variants of the Thermomyces lanuginosus lipase on a hydrophobic surface suggests a role for local flexibility. Colloids Surf B Biointerfaces 2008; 64:223-8. [DOI: 10.1016/j.colsurfb.2008.01.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 01/21/2008] [Accepted: 01/25/2008] [Indexed: 10/22/2022]
|
28
|
Datta S, Cecil C, Bhattacharyya D. Functionalized Membranes by Layer-By-Layer Assembly of Polyelectrolytes and In Situ Polymerization of Acrylic Acid for Applications in Enzymatic Catalysis. Ind Eng Chem Res 2008; 47:4586-4597. [PMID: 31130775 PMCID: PMC6533002 DOI: 10.1021/ie800142d] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This research work was directed toward the development of highly active, stable, and reusable functionalized polymeric membrane domains for enzymatic catalysis. Functionalized membranes were created by two different approaches. In the first approach, which involved alternative attachment of cationic and anionic polyelectrolytes, functionalization was performed using a layer-by-layer (LBL) assembly technique within a nylon-based microfiltration (MF) membrane. In the second approach, a hydrophobic polyvinylidene fluoride (PVDF) MF membrane was functionalized by the in situ polymerization of acrylic acid. The enzyme, glucose oxidase (GOX), was then electrostatically immobilized inside the functionalized membrane domains to study the catalytic oxidation of glucose to gluconic acid and H2O2. Characterization of the functionalized membranes, in terms of polyelectrolyte/polymer domains and permeate flux, was also conducted. The kinetics of H2O2 formation was discussed, along with the effects of residence time and pH on the activity of GOX. The stability and reusability of the electrostatically immobilized enzymatic system were also investigated.
Collapse
Affiliation(s)
- Saurav Datta
- Department of Chemical and Materials Engineering, UniVersity of Kentucky, Lexington, Kentucky 40506-0046
| | - Caitlyn Cecil
- Department of Chemical and Materials Engineering, UniVersity of Kentucky, Lexington, Kentucky 40506-0046
| | - D. Bhattacharyya
- Department of Chemical and Materials Engineering, UniVersity of Kentucky, Lexington, Kentucky 40506-0046
| |
Collapse
|
29
|
Glomm WR, Halskau, Ø, Hanneseth AMD, Volden S. Adsorption Behavior of Acidic and Basic Proteins onto Citrate-Coated Au Surfaces Correlated to Their Native Fold, Stability, and pI. J Phys Chem B 2007; 111:14329-45. [DOI: 10.1021/jp074839d] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
30
|
De Giglio E, Cometa S, Cioffi N, Torsi L, Sabbatini L. Analytical investigations of poly(acrylic acid) coatings electrodeposited on titanium-based implants: a versatile approach to biocompatibility enhancement. Anal Bioanal Chem 2007; 389:2055-63. [PMID: 17516054 DOI: 10.1007/s00216-007-1299-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Revised: 04/04/2007] [Accepted: 04/05/2007] [Indexed: 11/27/2022]
Abstract
A polyacrylic acid film was synthesized on titanium substrates from aqueous solutions via an electroreductive process for the first time. This work was done in order to develop a versatile coating for titanium-based orthopaedic implants that acts as both an effective bioactive surface and an effective anti-corrosion barrier. The chemical structure of the PAA coating was investigated by X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) was employed to evaluate the effect of annealing treatment on the morphology of the coatings in terms of their uniformity and porosity. Inductively coupled plasma mass spectrometry was used to measure ion concentrations in ion release tests performed on Ti-6Al-4V sheets modified with PAA coatings (annealed and unannealed). Results indicate that the annealing process produces coatings that possess considerable anti-corrosion performance. Moreover, the availability and the reactivity of the surface carboxylic groups were exploited in order to graft biological molecules onto the PAA-modified titanium implants. The feasibility of the grafting reaction was tested using a single aminoacid residue. A fluorinated aminoacid was selected, and the grafting reaction was monitored both by XPS, using fluorine as a marker element, and via quartz crystal microbalance (QCM) measurements. The success of the grafting reaction opens the door to the synthesis of a wide variety of PAA-based coatings that are functionalized with selected bioactive molecules and promote positive reactions with the biological system interfacing the implant while considerably reducing ion release into surrounding tissues.
Collapse
Affiliation(s)
- E De Giglio
- Department of Chemistry, University of Bari, Via E. Orabona 4, 70126, Bari, Italy.
| | | | | | | | | |
Collapse
|
31
|
Aravamudhan S, Kumar A, Mohapatra S, Bhansali S. Sensitive estimation of total cholesterol in blood using Au nanowires based micro-fluidic platform. Biosens Bioelectron 2007; 22:2289-94. [PMID: 17215119 DOI: 10.1016/j.bios.2006.11.027] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 10/02/2006] [Accepted: 11/20/2006] [Indexed: 10/23/2022]
Abstract
Determination of cholesterol level in blood is important in clinical applications. In this work, modified Au nanowires-electrochemical biosensor based on MEMS micro-fluidic platform is proposed for estimating total cholesterol in blood. This sensor consists of "aligned" Au nanowires as working electrode, platinum counter electrode deposited on the silicon platform and Ag/AgCl (3M KCl) reference electrode. The "aligned" Au nanowires are immobilized with cholesterol oxidase and cholesterol esterase using specific covalent chemistry. Further, Au nanowires promotes better electron transfer between the enzymes and electrodes, because of their large surface to volume ratio, small diffusion time, large electrical conductivity and their aligned nature. The modified Au nanowires showed a stable calibration line and a quasi-linear relationship between cholesterol level and current response in the range of 1-6 mM (in steps of 1 mM over the baseline blood serum). The sensitivity of the modified electrode was found to be about 69 nA/mM with good storage and interference stability.
Collapse
Affiliation(s)
- Shyam Aravamudhan
- BioMEMS and Microsystems Laboratory, Department of Electrical Engineering, University of South Florida, Tampa, FL 33620, USA
| | | | | | | |
Collapse
|
32
|
Gan BK, Kondyurin A, Bilek MMM. Comparison of protein surface attachment on untreated and plasma immersion ion implantation treated polystyrene: protein islands and carpet. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:2741-6. [PMID: 17243737 DOI: 10.1021/la062722v] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Surface attachment of the enzyme horseradish peroxidase (HRP) was studied on untreated and ion beam implanted polystyrene (PS) films. The PS films of 100 nm thickness on a silicon wafer were treated using the plasma immersion ion implantation (PIII) technique, with argon ions of energy 20 keV and fluences of up to 2 x 10(16) ions/cm2. Differential transmittance Fourier transform infrared (FTIR) spectra confirmed the presence of proteins on the PS surfaces by detection of the amide A, I, and II protein vibrations. Spectroscopic ellipsometry over the UV-vis spectral region provided the optical constants and thickness of the protein layer, while tapping mode atomic force microscopy (AFM) was used to image the protein distribution on the surface. The combination of AFM, ellipsometry, and FTIR analysis showed that, on the untreated PS surface, HRP formed islands 8 nm in height and 30 nm in lateral size, covering approximately 27% of the PS surface. After PIII modification of the PS surface, the protein covered 100% of the surface area.
Collapse
Affiliation(s)
- B K Gan
- Applied and Plasma Physics, School of Physics (A28), The University of Sydney, New South Wales 2006, Australia
| | | | | |
Collapse
|
33
|
Cooper MA, Singleton VT. A survey of the 2001 to 2005 quartz crystal microbalance biosensor literature: applications of acoustic physics to the analysis of biomolecular interactions. J Mol Recognit 2007; 20:154-84. [PMID: 17582799 DOI: 10.1002/jmr.826] [Citation(s) in RCA: 294] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The widespread exploitation of biosensors in the analysis of molecular recognition has its origins in the mid-1990s following the release of commercial systems based on surface plasmon resonance (SPR). More recently, platforms based on piezoelectric acoustic sensors (principally 'bulk acoustic wave' (BAW), 'thickness shear mode' (TSM) sensors or 'quartz crystal microbalances' (QCM)), have been released that are driving the publication of a large number of papers analysing binding specificities, affinities, kinetics and conformational changes associated with a molecular recognition event. This article highlights salient theoretical and practical aspects of the technologies that underpin acoustic analysis, then reviews exemplary papers in key application areas involving small molecular weight ligands, carbohydrates, proteins, nucleic acids, viruses, bacteria, cells and lipidic and polymeric interfaces. Key differentiators between optical and acoustic sensing modalities are also reviewed.
Collapse
Affiliation(s)
- Matthew A Cooper
- Akubio Ltd., 181 Cambridge Science Park, Cambridge, United Kingdom, UK.
| | | |
Collapse
|
34
|
Roy S, Vedala H, Choi W. Vertically aligned carbon nanotube probes for monitoring blood cholesterol. NANOTECHNOLOGY 2006; 17:S14-S18. [PMID: 21727348 DOI: 10.1088/0957-4484/17/4/003] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Detection of blood cholesterol is of great clinical significance. The amperometric detection technique was used for the enzymatic assay of total cholesterol. Multiwall carbon nanotubes (MWNTs), vertically aligned on a silicon platform, promote heterogeneous electron transfer between the enzyme and the working electrode. Surface modification of the MWNT with a biocompatible polymer, polyvinyl alcohol (PVA), converted the hydrophobic nanotube surface into a highly hydrophilic one, which facilitates efficient attachment of biomolecules. The fabricated working electrodes showed a linear relationship between cholesterol concentration and the output signal. The efficacy of the multiwall carbon nanotubes in promoting heterogeneous electron transfer was evident by distinct electrochemical peaks and higher signal-to-noise ratio as compared to the Au electrode with identical enzyme immobilization protocol. The selectivity of the cholesterol sensor in the presence of common interferents present in human blood, e.g. uric acid, ascorbic acid and glucose, is also reported.
Collapse
Affiliation(s)
- Somenath Roy
- Mechanical and Materials Engineering Department, Florida International University, Miami, FL 33174, USA
| | | | | |
Collapse
|
35
|
Abstract
Acoustic microsensors are commonly known as high-resolution mass-sensitive devices. This is a restricted view in many chemical and biosensor applications, especially in liquids. Sensitivity to non-gravimetric effects is a challenging feature of acoustic sensors. In this review we give an overview of recent developments in resonant sensors including micromachined devices and also list recent activity relating to the (bio)chemical interface of acoustic sensors. Major results from theoretical analysis of quartz crystal resonators, descriptive for all acoustic microsensors are summarized, and non-gravimetric contributions to the sensor signal from viscoelasticity and interfacial effects are discussed. We finally conclude with some future perspectives.
Collapse
Affiliation(s)
- Ralf Lucklum
- Institute for Micro and Sensor Systems (IMOS), Otto-von-Guericke-University, Magdeburg, Germany.
| | | |
Collapse
|