Article
Biochemistry & Molecular Biology
Jihoon Park, Hyun-Woo Shin, Joona Bang, June Huh
Summary: The study investigated the order-disorder transitions of core-shell bottle brush copolymer and its structural isomers using simulations and theoretical predictions, finding an optimal chain topology parameter lambda that minimizes incompatibility at ODT.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Physical
Shuaifang Zhang, Rajeev Kumar
Summary: We present an approach for constructing thermodynamically consistent time-dependent models for thin films of diblock copolymers in applied electric fields. The model is sensitive to initial conditions and shows transient behavior different from a model assuming a constant transport coefficient. Numerical results are qualitatively agreement with experiments, providing a systematic method for simulating the effects of electrolytes added to thin films containing diblock copolymers in the presence of applied electric fields.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Takafumi Ishibe, Tatsuya Kaneko, Yuto Uematsu, Hideo Sato-Akaba, Motonori Komura, Tomokazu Iyoda, Yoshiaki Nakamura
Summary: This study focuses on tuning the switching temperature of thermal conductivity using liquid crystalline block copolymers with different order-order transition temperature related to the types of mesogens in the side chain. The results show that BC films exhibit reversible thermal conductivity switching behaviors and thermal conductivity variation originating from the anisotropy of the internal structures. This highlights the potential application of BCs as thermal conductivity switching materials.
Article
Polymer Science
Bo H. Ren, Che Y. Chu, Bo S. Jhang
Summary: This study demonstrates the manipulation of order-order transition in a nanocomposite film by applying a low-intensity external magnetic field. The film transforms from a hexagonally packed cylindrical structure to a lamellar structure under magnetic thermal annealing. This work represents a significant advance in the magnetic field directed self-assembly of block copolymers.
Article
Polymer Science
Mingyang Chen, Yuguo Chen, Yanyan Zhu, Ying Jiang, David Andelman, Xingkun Man
Summary: We investigated the influence of chain flexibility on the self-assembly behavior of symmetric diblock copolymers (BCPs) in thin film confinement. Using worm-like chain (WLC) self-consistent field theory, we studied the stability of parallel and perpendicular orientations of BCP lamellar phases under varying chain flexibilities. The results showed that the stability of perpendicular lamellae increases with chain rigidity, except for the case of rigid chains on rough substrates where the stability decreases. We also demonstrated the effect of substrate roughness on the critical value of substrate preference for the transition from perpendicular-to-parallel lamellar phases.
Article
Polymer Science
Karthika Madathil, Banafsheh Hekmatnia, Haleh Ardebili, Gila E. Stein
Summary: This study examines the impact of solvent composition and solution-casting process on the structure and properties of a lamellar sulfonated pentablock copolymer (SPC) membrane. The results show that sequential deposition of multiple layers can predict the structure of dry films and processing conditions strongly influence through-plane transport properties. This study provides valuable insights for optimizing critical transport properties.
Article
Materials Science, Characterization & Testing
Wooseop Lee, Jiho Kim, Seungyun Jo, Boknam Chae, Hyungju Ahn, Du Yeol Ryu
Summary: This study presents a simple and effective method to probe the chemical distribution in self-assembled block copolymer films, and reveals the impact of solvent vapor annealing and thermal annealing on the chemical distribution, which is crucial for the formation of high-contrast chemical patterns.
Article
Polymer Science
Anabella A. Abate, Cristian M. Piqueras, Daniel A. Vega
Summary: When a cylinder forming triblock copolymer thin film is exposed to supercritical carbon dioxide, it undergoes an order-order phase transition from parallel to perpendicularly oriented cylinders. Defects modify the energetic barriers for nucleation during the phase transition, with topological defects in the primitive phase surviving the transition to provide a lower bound for the density of defects in the post-transitional phase. Control over the orientational order in the primitive phase can be used to manipulate order and defects in the transversely isotropic hexagonal pattern.
Article
Polymer Science
Tomohisa Watanabe, Yubo Wang, Tomoko Ono, Satoru Chimura, Takuya Isono, Kenji Tajima, Toshifumi Satoh, Shin-ichiro Sato, Daichi Ida, Takuya Yamamoto
Summary: The topology effects of cyclization on thermal phase transition behaviors were investigated for amphiphilic Pluronic copolymers. It was found that the effect of cyclization on cloud point and critical temperature depended on the block sequence.
Article
Polymer Science
Aynur Guliyeva, Helene Pung, Sylvie Tence-Girault, Marc Rebillat, Anatoli Serghei, Matthieu Gervais, Cyrille Sollogoub, Sebastien Roland
Summary: This study observed the self-assembly behavior of high molecular weight commercially available low chi ABA triblock copolymers with ionic liquids without the need for additional annealing. The addition of the ionic liquid was found to influence the morphology, glass transition, and domain spacing of the self-assembled structures. Furthermore, the ionic liquid enhanced the long-range ordering of the copolymer morphology.
POLYMER INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Gang Zhang, Zhongyao Qin, Yu Qian, Jiaming Zhu
Summary: This study numerically investigates the temporal evolution of microstructure and kinetics of phase separation under electric fields for binary polymer blends. It reveals that the electric field has a significant influence on the morphological development and kinetic process of phase separation, with different rules observed at off-critical and critical compositions. The study also provides insights into the design of anisotropic microstructures by electric fields and their application in producing polymeric composite materials with superior properties.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Polymer Science
Isabella R. Dorsman, Matthew J. Derry, Victoria J. Cunningham, Steven L. Brown, Clive N. Williams, Steven P. Armes
Summary: The study discovered an unexpected reduction in dispersion viscosity when heating block copolymer vesicles above a critical temperature, with a thermal transition from vesicles to worms and then to spheres observed. Moreover, the addition of a suitable comonomer was found to lower the critical onset temperature required for the vesicle-to-worm transition, as confirmed by rheology and small-angle X-ray scattering experiments. The thermal transitions observed were irreversible on normal experimental timescales.
Article
Materials Science, Multidisciplinary
Yanglin Wang, Min Jiang, Runze Wang, Zunhong Wen, Hongxiao Li, Yuping Ren, Gaowu Qin
Summary: The phase equilibria and phase transformations of Fe-Pt-Au alloys were investigated, and it was found that the addition of Au promotes the ordering process. The mechanism behind this phenomenon was analyzed using experiments and thermodynamics.
Article
Chemistry, Multidisciplinary
Krishan Kumar, Reddicherla Umapathi, Kalyan Ramesh, Seung-Kyu Hwang, Kwon Taek Lim, Yun Suk Huh, Pannuru Venkatesu
Summary: This study focused on thermoresponsive polymers synthesized using RAFT polymerization and investigated the influence of proteins on their phase behavior and aggregation. Various biophysical techniques were used to explore the interactions between the copolymer and proteins, revealing changes in LCST. The research provides insights into the interactions between heme proteins and block copolymers, which can guide the design of biomimetic surfaces and copolymer-protein bioconjugates.
Article
Polymer Science
Wennie Yun Lee, Dana Chapman, Fei Yu, William R. T. Tait, R. Paxton Thedford, Guillaume Freychet, Mikhail Zhernenkov, Lara A. Estroff, Ulrich B. Wiesner
Summary: Self-assembled block copolymer thin films and their nanocomposites have diverse applications due to their nanostructures. Optical super-resolution microscopy (OSRM) has emerged as an alternative method for characterizing nanoscopic polymer morphology. This study focuses on self-assembled triblock terpolymer thin films with all three blocks exposed at the top surface, and demonstrates the use of OSRM for multicolor characterization of chemically distinct nanodomains.
Article
Chemistry, Multidisciplinary
Martin Reifarth, Marek Bekir, Alain M. Bapolisi, Evgenii Titov, Fabian Nusshardt, Julius Nowaczyk, Dmitry Grigoriev, Anjali Sharma, Peter Saalfrank, Svetlana Santer, Matthias Hartlieb, Alexander Boeker
Summary: A cationic surfactant with a spiropyrane unit was prepared, demonstrating adjustable surface-active characteristics with dual responsiveness. The reversible conversion of the spiropyrane unit to a zwitterionic merocyanine was controlled by adjusting pH value and light, resulting in pH-dependent photoactivity. The underlying switching processes were investigated and a thermodynamic explanation was provided. The complex stimuli-responsive behavior enables remote-control of colloidal systems and can be applied in pH-dependent manipulation of oil-in-water emulsions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Stacy M. Copp, Ryan L. Hamblin, Kirstie Swingle, Durgesh Rai, Volker S. Urban, Sergei A. Ivanov, Gabriel A. Montano
Summary: Amphiphilic block copolymers with weak polyelectrolyte blocks can assemble stimulus-responsive nanostructures and interfaces. This study investigates whether the pH-driven morphological response of polyelectrolyte-bearing nanostructures also affects the interactions of these nanostructures with molecules in solution, using a micelle model system. The study finds that the FRET efficiency exhibits complex nonmonotonic behavior as a function of pH, indicating that the average separation of micelles and acceptor fluorophores is not strictly correlated with micelle swelling.
Article
Chemistry, Multidisciplinary
Zhi Yang, Marcus B. Foston, Hugh O'Neill, Volker S. Urban, Arthur Ragauskas, Barbara R. Evans, Brian H. Davison, Sai Venkatesh Pingali
Summary: Different thermochemical pretreatments have been developed and employed to enhance the efficiency of second-generation bioethanol production from lignocellulosic biomass. The structural evolution of noncellulosic switchgrass polymers during dilute acid pretreatment was studied using in-situ small-angle neutron scattering (in-situ SANS), revealing the formation of aggregate particles derived from hemicellulose and lignin. The results suggest that both lignin and hemicellulose can form aggregate particles within plant cell walls during pretreatment.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Polymer Science
Michele Fromel, Christian W. Pester
Summary: This study presents a simple method to chemically modify the surface of polycarbonate (PC) with super-hydrophilic polymer brushes. By using this method, PC can be used in a wider range of applications and scientists and engineers can take advantage of its attractive physical properties without being limited by its hydrophobic nature.
Article
Computer Science, Software Engineering
William T. Heller, John Hetrick, Jean Bilheux, Jose M. Borreguero Calvo, Wei-Ren Chen, Lisa DeBeer-Schmitt, Changwoo Do, Mathieu Doucet, Michael R. Fitzsimmons, William F. Godoy, Garrett E. Granroth, Steven Hahn, Lilin He, Fahima Islam, Jiao Lin, Kenneth C. Littrell, Marshall McDonnell, Jesse McGaha, Peter F. Peterson, Sai Venkatesh Pingali, Shuo Qian, Andrei T. Savici, Yingrui Shang, Christopher B. Stanley, Volker S. Urban, Ross E. Whitfield, Chen Zhang, Wenduo Zhou, Jay Jay Billings, Matthew J. Cuneo, Ricardo M. Ferraz Leal, Tianhao Wang, Bin Wu
Summary: This article describes the drtsans software package developed at Oak Ridge National Laboratory for data reduction in small-angle neutron scattering experiments. The software has positively impacted the scientific programs on the EQ-SANS, GP-SANS, and Bio-SANS instruments.
Article
Chemistry, Physical
Volker S. Urban, Raquel L. Lieberman, Wellington C. Leite, Yuqi Wu, Sai Venkatesh Pingali
Summary: This study investigates the impact of the single chain detergent DDM on the morphology of bicelles. DDM is able to reshape the bicelles at different temperatures, which is crucial for understanding lipid membrane self-organization and optimizing lipid mimics in membrane biology research.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Biochemistry & Molecular Biology
Viswanathan Gurumoorthy, Utsab R. Shrestha, Qiu Zhang, Sai Venkatesh Pingali, Eric T. Boder, Volker S. Urban, Jeremy C. Smith, Loukas Petridis, Hugh O'Neill
Summary: c-Src kinase is a non-receptor tyrosine kinase that phosphorylates signaling proteins in cancers. This study focuses on the N-terminal disordered region (SH4UD) and its interactions with other domains of c-Src kinase. The results show that the presence of SH4UD leads to structural changes in the regulatory domains (SH3-SH2), indicating the importance of the disordered region for allosteric interactions. This study provides insights that may aid in the development of therapeutic interventions targeting the regulatory domains of c-Src kinase.
Article
Pharmacology & Pharmacy
Daniel Braganca Viana, Maria Mathieu-Gaedke, Nadia Miriceia Leao, Alexander Boeker, Daniel Cristian Ferreira Soares, Ulrich Glebe, Marli Luiza Tebaldi
Summary: This study successfully synthesized thermoresponsive protein-polymer conjugates, which can be used as novel drug delivery systems for targeted drug delivery to cancer tissue through the bloodstream. The copolymers of N-vinylcaprolactam and 2-(dimethy-lamino)ethyl methacrylate were grafted onto bovine serum albumin, with a cloud point observed at around 40 degrees Celsius. These conjugates exhibited high cisplatin loading capacity and significant cytotoxicity against human breast cancer cells, making them potential carriers for drug delivery or other biomedical applications.
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Applied
Madison A. A. Oehler, Douglas G. G. Hayes, Doris H. H. D'Souza, Manjula Senanayake, Viswanathan Gurumoorthy, Sai Venkatesh Pingali, Hugh M. M. O'Neill, Wim Bras, Volker S. S. Urban
Summary: The study demonstrates that the antimicrobial peptide melittin can be solubilized in an active form in bicontinuous microemulsions. Melittin interacts with the surfactant and affects the structure of the microemulsion. Incorporating melittin enhances the antimicrobial activity of the microemulsion against bacteria.
JOURNAL OF SURFACTANTS AND DETERGENTS
(2023)
Article
Polymer Science
Maria Mathieu-Gaedke, Alexander Boeker, Ulrich Glebe
Summary: Proteins, with their diverse properties developed over millions of years, have great potential for applications in biomedicine and industry. However, their stability is limited and exposure to certain conditions can cause denaturation or aggregation. Modification with synthetic polymers is a powerful approach to enhance protein stability. Various methods have been established to characterize protein-polymer conjugates, but determining the structural integrity of proteins in biohybrid materials and the arrangement of polymer chains around proteins remains challenging. This Perspective provides an overview of different analysis techniques, discusses their applicability and feasibility, and presents current literature examples. The focus is on techniques such as nuclear magnetic resonance spectroscopy, size exclusion chromatography coupled with multi-angle laser light scattering, analytical ultracentrifugation, and small-angle scattering, which provide insights into protein structure and polymer conformation.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2023)
Editorial Material
Polymer Science
Alexander Boeker
Article
Polymer Science
Kirsten Bell, Sarah Freeburne, Adam Wolford, Christian W. Pester
Summary: This study discusses the control of polymerization using a heterogeneous photocatalyst based on fluorescein polymer brushes tethered to micron-scale glass supports. It shows that the PET-RAFT polymerization catalyzed by FPB@SiO2 provides high conversions, controlled molecular weights, and narrow molecular weight distributions for various monomers. Additionally, the catalyst can perform PET-RAFT reactions on a gram scale in the presence of oxygen, while allowing easy catalyst recovery through filtration.
Article
Chemistry, Multidisciplinary
Ulrike Doering, Dmitry Grigoriev, Tino Riske, Andreas Fery, Alexander Boeker
Summary: The mechanical properties of proteinaceous and composite microcapsules loaded with oil were measured using SFM and evaluated with the Reissner model. The results showed significantly higher Young's moduli in protein capsules due to intermolecular crosslinking, while conformational restrictions in composite microcapsules led to reduced elasticity.
Meeting Abstract
Biophysics
Viswanathan Gurumoorthy, Utsab Shrestha, Sai Venkatesh Pingali, Jeremy C. Smith, Volker Urban, Loukas Petridis, Hugh M. O'Neill
BIOPHYSICAL JOURNAL
(2022)
Article
Chemistry, Physical
Ulrike Doering, Dmitry Grigoriev, Kosti Tapio, Ilko Bald, Alexander Boker
Summary: We propose a simple and eco-friendly method for the formation of composite protein-mineral-microcapsules induced by ultrasound treatment. Through the use of high-intensity ultrasound, protein- and nanoparticle-stabilized oil-in-water emulsions loaded with different oils were prepared. The resulting capsules have thin composite mineral proteinaceous shells made with various types of pre-modified nanoparticles, showing potential applications in pharmaceutical science, cosmetics, and food technology.
