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Coceancigh H, Xue L, Nagasaka S, Higgins DA, Ito T. Solvent-Induced Swelling Behaviors of Microphase-Separated Polystyrene- block-Poly(ethylene oxide) Thin Films Investigated Using In Situ Spectroscopic Ellipsometry and Single-Molecule Fluorescence Microscopy. J Phys Chem B 2022; 126:8338-8349. [PMID: 36219821 DOI: 10.1021/acs.jpcb.2c05025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Block copolymers have attracted considerable interest in the fields of nanoscience and nanotechnology because these polymers afford well-defined nanostructures via self-assembly. An in-depth understanding of solvent effects on the physicochemical properties of these microdomains is crucial for their preparation and utilization. Herein, we employed in situ spectroscopic ellipsometry and single-molecule fluorescence techniques to gain detailed insights into microdomain properties in polystyrene-block-poly(ethylene oxide) (PS-b-PEO) films exposed to ethanol- and water-saturated N2. We observed a quick increase and a subsequent gradual decrease in the ellipsometric thickness of PS-b-PEO films upon exposure to ethanol-saturated N2. This observation was unexpected because ethanol-saturated N2 induced negligible thickness change for PS and PEO homopolymer films. The similarity in maximum thickness gain observed under ethanol- and water-saturated N2 implied the swelling of PEO microdomains. Ethanol vapor permeation through the PEO microdomains was supported by the redshift of the ensemble and single-molecule fluorescence emission of Nile red in PS-b-PEO films. Single-molecule tracking data showed the initial enhancement and subsequent reduction of the diffusion of hydrophilic sulforhodamine B molecules in PS-b-PEO films upon exposure to ethanol-saturated N2, consistent with the spectroscopic ellipsometry results. The higher ethanol susceptibility of the PEO microdomains was attributable to their amorphous nature, as shown by FTIR data.
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Affiliation(s)
- Herman Coceancigh
- Department of Chemistry, Kansas State University, Manhattan, Kansas66506-0401, United States
| | - Lianjie Xue
- Department of Chemistry, Kansas State University, Manhattan, Kansas66506-0401, United States
| | - Shinobu Nagasaka
- Department of Chemistry, Kansas State University, Manhattan, Kansas66506-0401, United States
| | - Daniel A Higgins
- Department of Chemistry, Kansas State University, Manhattan, Kansas66506-0401, United States
| | - Takashi Ito
- Department of Chemistry, Kansas State University, Manhattan, Kansas66506-0401, United States
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Ito T, Coceancigh H, Yi Y, Sharma JN, Parks FC, Flood AH. Nanoporous Thin Films Formed from Photocleavable Diblock Copolymers on Gold Substrates Modified with Thiolate Self-Assembled Monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9259-9268. [PMID: 32683869 DOI: 10.1021/acs.langmuir.0c01572] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nanoporous thin films formed on electrodes are considered functional elements of electrochemical sensing systems, thus motivating methods for their development. We report a preparative strategy detailing the effects of surface modification of gold substrates with thiolate self-assembled monolayers (SAMs) on the properties of nanoporous thin films derived from polystyrene-block-poly(ethylene oxide) having a photocleavable o-nitrobenzyl ester junction (PS-hν-PEO). Two PS-hν-PEO having similar PEO volume fractions (≈0.2) but different molecular weights (10 and 23 kg/mol) were used to prepare films (30-100 nm thick) spin-cast on gold substrates unmodified and modified with cysteamine, thioctic acid, and 6-hydroxy-1-hexanethiol SAMs. Solvent vapor annealing followed by PEO removal led to the formation of nanopores with average diameters of 12 and 19 nm from the smaller and larger PS-hν-PEO, respectively. Cyclic voltammograms of 1,1'-ferrocenedimethanol showed that nanoporous films on cysteamine SAMs afforded nanopores reaching the underlying substrates at higher density than those on the other substrates. This result was attributed to balanced affinity of the cysteamine SAM surface with PS and PEO, which enhanced the vertical orientation of PEO microdomains. The generation of carboxyl groups associated with the photocleavage reaction was revealed by pH-dependent changes in the voltammogram of Fe(CN)63- that reflected electrostatic effects regulated by the protonation state of the carboxyl groups. The SAMs underneath the nanoporous films could be replaced by treatment with a thiol solution, as verified by voltammograms of l-ascorbic acid. These results suggest that thiolate SAM modification provides a simple means to control the interfacial orientation of PEO microdomains in thin PS-hν-PEO films.
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Affiliation(s)
- Takashi Ito
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506-0401, United States
| | - Herman Coceancigh
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506-0401, United States
| | - Yi Yi
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Jay N Sharma
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506-0401, United States
| | - Fred C Parks
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Amar H Flood
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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Zhou P, Yao L, Su B. Fabrication, Characterization, and Analytical Application of Silica Nanopore Array-Modified Platinum Electrode. ACS APPLIED MATERIALS & INTERFACES 2020; 12:4143-4149. [PMID: 31886640 DOI: 10.1021/acsami.9b20165] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this work, we report a new approach to fabricate the nanopore array electrode (NAE) by transferring silica nanochannel membrane (SNM) to the surface of Pt electrode (0.5 mm in diameter) sealed by glass capillary (designated as Pt-NAE for simplicity). The SNM is supported via the irreversible covalent-bond formation with the surrounding glass capillary treated by plasma, thus providing long-term stability to Pt-NAE. Meanwhile, this fabrication process does not require pregrafting or premodification of Pt electrode surface, providing well-defined active surface domains. Thanks to the small pore diameter (∼2.3 nm) and negatively charged channel walls, the SNM is permselective and thus the electrochemical behavior of Pt-NAE is dependent on both electrolyte concentration and charge state of redox molecules. The permeability of SNM was determined by the scanning electrochemical microscopy (SECM) approach curve measurements coupled with finite-element simulations from a quantitative viewpoint. The permeability of anionic Ru(CN)64- was varied from 150 to 10.3 μm s-1 as the electrolyte concentration decreased from 1.0 to 0.01 M, while there is no obvious change for cationic Ru(NH3)63+. Finally, the as-prepared Pt-NAE is able to continuously monitor dissolved oxygen for up to 2 h in a solution containing biofouling reagents, exhibiting an enhanced antifouling ability and therefore excellent current stability. We believe the NAE with unique mass transport properties can be extended further for other analytical applications.
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Affiliation(s)
- Ping Zhou
- Institute of Analytical Chemistry, Department of Chemistry , Zhejiang University , Hangzhou 310058 , China
| | - Lina Yao
- Institute of Analytical Chemistry, Department of Chemistry , Zhejiang University , Hangzhou 310058 , China
| | - Bin Su
- Institute of Analytical Chemistry, Department of Chemistry , Zhejiang University , Hangzhou 310058 , China
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Harandizadeh Z, Ito T. Block Copolymer‐Derived Recessed Nanodisk‐Array Electrodes as Platforms for Folding‐Based Electrochemical DNA Sensors. ChemElectroChem 2019. [DOI: 10.1002/celc.201901562] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Zeinab Harandizadeh
- Department of Chemistry Kansas State University 213 CBC Building, Manhattan Kansas 66506-0401 USA
| | - Takashi Ito
- Department of Chemistry Kansas State University 213 CBC Building, Manhattan Kansas 66506-0401 USA
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Coceancigh H, Higgins DA, Ito T. Optical Microscopic Techniques for Synthetic Polymer Characterization. Anal Chem 2018; 91:405-424. [PMID: 30350610 DOI: 10.1021/acs.analchem.8b04694] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Herman Coceancigh
- Department of Chemistry , Kansas State University , 213 CBC Building , Manhattan , Kansas 66506-0401 , United States
| | - Daniel A Higgins
- Department of Chemistry , Kansas State University , 213 CBC Building , Manhattan , Kansas 66506-0401 , United States
| | - Takashi Ito
- Department of Chemistry , Kansas State University , 213 CBC Building , Manhattan , Kansas 66506-0401 , United States
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Ghimire G, Coceancigh H, Yi Y, Ito T. Electrochemical Characterization and Catalytic Application of Gold-Supported Ferrocene-Containing Diblock Copolymer Thin Films in Ethanol Solution. ACS APPLIED MATERIALS & INTERFACES 2017; 9:2906-2913. [PMID: 28019098 DOI: 10.1021/acsami.6b11181] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This paper reports the electrochemical behavior and catalytic property of electrode-supported thin films of polystyrene-block-poly(2-(acryloyloxy)ethyl ferrocenecarboxylate) (PS-b-PAEFc) in an ethanol (EtOH) solution. The electrochemical properties of PS-b-PAEFc films with different PAEFc volume fractions (fPAEFc = 0.47, 0.30, and 0.17) in 0.1 M ethanolic sodium hexafluorophosphate (NaPF6) were compared with those in an acetonitrile (MeCN) solution of 0.1 M tetrabutylammonium hexafluorophosphate. Pristine PS-b-PAEFc films did not afford significant faradaic currents in the EtOH solution because EtOH is a nonsolvent for both PS and PAEFc. However, the films could be rendered redox-active in the EtOH solution by applying potentials in the MeCN solution to induce the redox-associated incorporation of the supporting electrolytes into the films. Atomic force microscopy images verified the stability of PAEFc microdomains upon electrochemical measurements in these solutions. Cyclic voltammograms measured in the EtOH solution for PS-b-PAEFc with the larger fPAEFc were diffusion-controlled regardless of ellipsometric film thickness (23-152 nm) at relatively slow scan rates, in contrast to those in the MeCN solution that were controlled by surface-confined redox species. The electron propagation efficiency in the EtOH solution was significantly lower than that in the MeCN solution because of the poorer swelling of the films, which limited the migration of counterions and the collisional motions of the ferrocene moieties. PS-b-PAEFc films were applied as electrochemically responsive heterogeneous catalysts based on the ferrocenium moieties for Michael addition reaction between methyl vinyl ketone and ethyl 2-oxocyclopentanecarboxylate (E2OC) in 0.1 M NaPF6/EtOH. The catalytic activities of thin films were similar regardless of fPAEFc, suggesting that the catalytic reaction took place for the reactants that could penetrate through the film and reach PAEFc microdomains communicable with the underlying electrode. Interestingly, the permeability of PS-b-PAEFc films provided a means to control the reaction selectivity, as suggested by negligible reaction of E2OC with trans-4-phenyl-3-buten-2-one.
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Affiliation(s)
- Govinda Ghimire
- Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Herman Coceancigh
- Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Yi Yi
- Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Takashi Ito
- Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506-0401, United States
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Sapkota DR, Tran-Ba KH, Elwell-Cuddy T, Higgins DA, Ito T. Single-Molecule Tracking Study of the Permeability and Transverse Width of Individual Cylindrical Microdomains in Solvent-Swollen Polystyrene-block-poly(ethylene oxide) Films. J Phys Chem B 2016; 120:12177-12183. [DOI: 10.1021/acs.jpcb.6b08368] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dol Raj Sapkota
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Khanh-Hoa Tran-Ba
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Trevor Elwell-Cuddy
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Daniel A. Higgins
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Takashi Ito
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
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Yao D, Zhang K, Chen Y. Microphase separation of poly(tert-butyl methacrylate)-block-polystyrene diblock copolymers to form perforated lamellae. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.03.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Ghimire G, Yi Y, Derylo MA, Baker LA, Ito T. Electron Propagation within Redox-Active Microdomains in Thin Films of Ferrocene-Containing Diblock Copolymers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:12307-12314. [PMID: 26485062 DOI: 10.1021/acs.langmuir.5b02996] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This paper reports the electrochemical behavior of redox-active microdomains in thin films of ferrocene-containing diblock copolymers, polystyrene-block-poly(2-(acryloyloxy)ethyl ferrocenecarboxylate) (PS-b-PAEFc). PS-b-PAEFc with different PAEFc volume fractions (PS154-b-PAEFc51, PS154-b-PAEFc26, and PS154-b-PAEFc12, where the subscripts represent the polymerization degree of each block; f(PAEFc) = 0.47, 0.30, and 0.17, respectively) was synthesized by sequential atom transfer radical polymerization. PS-b-PAEFc films of controlled thicknesses (20-160 nm) were prepared on gold substrates via spin-coating and characterized by ellipsometry. Microdomains were observed via atomic force microscopy on the surfaces of PS154-b-PAEFc51 and PS154-b-PAEFc26 thin films but not on the surfaces of PS154-b-PAEFc12 thin films. Electrochemical behavior of films was assessed by cyclic voltammetry and chronocoulometry in acetonitrile solution. The redox potential of ferrocene moieties was similar (ca. + 0.29 V vs Fc(+)/Fc) regardless of fPAEFc and film thickness. For PS154-b-PAEFc51 and PS154-b-PAEFc26, thicker films afforded larger faradaic peak currents and exhibited diffusion-controlled voltammograms at faster sweep rates. PS154-b-PAEFc26 produced voltammograms less influenced by solvent-induced swelling than PS154-b-PAEFc51, reflecting the improved morphological stability of PAEFc microdomains by redox-inert PS frameworks. In contrast, PS154-b-PAEFc12 films yielded similar faradaic peak currents regardless of film thickness and exhibited voltammograms indicative of surface-confined species. These observations suggest that PS154-b-PAEFc51 and PS154-b-PAEFc26 films contain continuous PAEFc microdomains extending from the electrode to the surface, in contrast to the PS154-b-PAEFc12 films which contain isolated PAEFc microdomains buried within the PS matrix. Electron propagation took place only through PAEFc microdomains that could electrically communicate with the underlying electrode. Apparent diffusion coefficients within PAEFc microdomains were similar (≈ 2 × 10(-11) cm(2)/s) for PS154-b-PAEFc51 and PS154-b-PAEFc26. The relatively low efficiency in electron propagation was attributable to ineffective electron self-exchange reaction within the PAEFc microdomains and/or limited counterion migration through the acetonitrile-swollen microdomains. These results provide guidance in design of redox-active metalloblock copolymers for various applications, which include electrocatalysis, electrochemical mediation in enzyme sensors, and redox-controlled molecular deposition.
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Affiliation(s)
- Govinda Ghimire
- Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Yi Yi
- Department of Chemistry, Indiana University , 800 E Kirkwood Ave., Bloomington, Indiana 47405, United States
| | - Maksymilian A Derylo
- Department of Chemistry, Indiana University , 800 E Kirkwood Ave., Bloomington, Indiana 47405, United States
| | - Lane A Baker
- Department of Chemistry, Indiana University , 800 E Kirkwood Ave., Bloomington, Indiana 47405, United States
| | - Takashi Ito
- Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506-0401, United States
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Ito T. Electron Hopping through Redox Moieties Anchored to Well-Defined Nanostructures. CHEM REC 2015; 15:1148-50. [PMID: 26294038 DOI: 10.1002/tcr.201510006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Takashi Ito
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas, 66506-0401, USA.
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Higgins DA, Park SC, Tran-Ba KH, Ito T. Single-Molecule Investigations of Morphology and Mass Transport Dynamics in Nanostructured Materials. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2015; 8:193-216. [PMID: 26132347 DOI: 10.1146/annurev-anchem-071114-040153] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Nanostructured materials such as mesoporous metal oxides and phase-separated block copolymers form the basis for new monolith, membrane, and thin film technologies having applications in energy storage, chemical catalysis, and separations. Mass transport plays an integral role in governing the application-specific performance characteristics of many such materials. The majority of methods employed in their characterization provide only ensemble data, often masking the nanoscale, molecular-level details of materials morphology and mass transport. Single-molecule fluorescence methods offer direct routes to probing these characteristics on a single-molecule/single-nanostructure basis. This article provides a review of single-molecule studies focused on measurements of anisotropic diffusion, adsorption, partitioning, and confinement in nanostructured materials. Experimental methods covered include confocal and wide-field fluorescence microscopy. The results obtained promise to deepen our understanding of mass transport mechanisms in nanostructures, thus aiding in the realization of advanced materials systems.
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Affiliation(s)
- Daniel A Higgins
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506-0401; ,
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Tran-Ba KH, Higgins DA, Ito T. Fluorescence Recovery after Photobleaching and Single-Molecule Tracking Measurements of Anisotropic Diffusion within Identical Regions of a Cylinder-Forming Diblock Copolymer Film. Anal Chem 2015; 87:5802-9. [PMID: 25923826 DOI: 10.1021/acs.analchem.5b01041] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This work demonstrates ensemble and single-molecule diffusion measurements within identical regions of a cylinder-forming polystyrene-poly(ethylene oxide) diblock copolymer (PS-b-PEO) film using fluorescence recovery after photobleaching (FRAP) and single-molecule tracking (SMT). A PS-b-PEO film (∼4 μm thick) with aligned cylindrical PEO microdomains containing 10 μM sulforhodamine B (SRB) was prepared by directional solvent-vapor penetration (SVP) of 1,4-dioxane. The ensemble diffusion behavior of SRB in the microdomains was assessed in FRAP studies of circular photobleached regions (∼7 μm in diameter). The SRB concentration was subsequently reduced by additional photobleaching, and the diffusion of individual SRB molecules was explored using SMT in the identical area (∼16 × 16 μm(2)). The FRAP data showed anisotropic fluorescence recovery, yielding the average microdomain orientation. The extent of fluorescence recovery observed (∼90%) demonstrated long-range microdomain connectivity, while the recovery time dependence provided an ensemble measurement of the SRB diffusion coefficient within the cylindrical microdomains. The SMT data exhibited one-dimensional diffusion of individual SRB molecules along the SVP direction across the entire film thickness, as consistent with the FRAP results. Importantly, the average of the single-molecule diffusion coefficients was close to the value obtained from FRAP in the identical area. In some cases, SMT offered smaller diffusion coefficients than FRAP, possibly due to contributions from SRB molecules confined within short PEO microdomains. The implementation of FRAP and SMT measurements in identical areas provides complementary information on molecular diffusion with minimal influence of sample heterogeneity, permitting direct comparison of ensemble and single-molecule diffusion behavior.
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Affiliation(s)
- Khanh-Hoa Tran-Ba
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Daniel A Higgins
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Takashi Ito
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
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Stable domain size and conformational segregation of short and long blocks during microphase separation in random block copolymers. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.02.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Robben KC, Tran-Ba KH, Ito T, Higgins DA. Trajectory-Profile-Guided Single Molecule Tracking for Assignment of One-Dimensional Diffusion Trajectories. Anal Chem 2014; 86:10820-7. [DOI: 10.1021/ac502881u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Kevin C. Robben
- Department of Chemistry, Kansas State University, 213
CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Khanh-Hoa Tran-Ba
- Department of Chemistry, Kansas State University, 213
CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Takashi Ito
- Department of Chemistry, Kansas State University, 213
CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Daniel A. Higgins
- Department of Chemistry, Kansas State University, 213
CBC Building, Manhattan, Kansas 66506-0401, United States
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Pandey B, Cox CB, Thapa PS, Ito T. Potentiometric Response Characteristics of Oxide-Coated Gallium Electrodes in Aqueous Solutions. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2014.07.083] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Tran-Ba KH, Higgins DA, Ito T. Single-Molecule Tracking Studies of Flow-Induced Microdomain Alignment in Cylinder-Forming Polystyrene–Poly(ethylene oxide) Diblock Copolymer Films. J Phys Chem B 2014; 118:11406-15. [DOI: 10.1021/jp507594t] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Khanh-Hoa Tran-Ba
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Daniel A. Higgins
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
| | - Takashi Ito
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, United States
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