Article
Chemistry, Physical
Leonid I. Klushin, Alexander M. Skvortsov, Alexey A. Polotsky, Anna S. Ivanova, Friederike Schmid
Summary: A novel class of responsive polymer brushes with controllable grafting density has been proposed in this study, using end-grafted polymer chains that have an affinity to the substrate. The dense layer and the outer brush can be seen as coexisting microphases, with the effective grafting density controlled by adsorption strength. Numerical self-consistent field calculations and scaling arguments demonstrate the reversible and controlled changes in grafting density in response to environmental parameters.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Polymer Science
Michele Laus, Riccardo Chiarcos, Valentina Gianotti, Diego Antonioli, Katia Sparnacci, Gianmarco Munao, Giuseppe Milano, Antonio De Nicola, Michele Perego
Summary: This study investigated the grafting process of partially deuterated and fully hydrogenated statistical copolymers onto a silicon substrate, analyzing the evolution of brush thickness and composition over time. The results showed a decrease in grafting density of deuterated polymers and an increase in grafting density of hydrogenated polymers, indicating simultaneous grafting and degrafting reactions. Additionally, an increase in molecular weight of hydrogenated polymers led to a decrease in total grafting density, reaching a limiting value when the molecular weight of incoming polymer equaled that of the preformed brush.
Article
Polymer Science
Riccardo Chiarcos, Diego Antonioli, Valentina Gianotti, Michele Laus, Gianmarco Munao, Giuseppe Milano, Antonio De Nicola, Michele Perego
Summary: In this study, two copolymers were thermally grafted from melt to a silicon wafer, and it was observed that the lower molecular weight component of the blend preferentially grafted to the polymeric brush layer. The enrichment of short chains in the brush layer was found to be independent of time. Molecular dynamics simulations supported this observation, providing insights for further investigation and control of brush layer characteristics.
Article
Polymer Science
Diego Antonioli, Riccardo Chiarcos, Valentina Gianotti, Margherita Terragno, Michele Laus, Gianmarco Munao, Giuseppe Milano, Antonio De Nicola, Michele Perego
Summary: In this study, the grafting reaction of copolymers with different compositions onto a silicon wafer showed that lower molecular weight components are selectively incorporated into the polymeric brush. The time, temperature, and composition of blends were found to systematically affect the final brush layer composition. Hybrid particle-field simulations suggested that the preference of short chains to react with the silicon surface is influenced by the number of chains in contact with silica and the substrate surface area occupied by a single chain.
Review
Engineering, Biomedical
Danyang Li, Lizhou Xu, Jing Wang, Julien E. Gautrot
Summary: Responsive polymer brushes are capable of conformational and chemical changes in response to external stimuli, offering unique opportunities for the control of bio-nano interactions. They can be designed on a wide range of nanomaterial surfaces without compromising their physical and imaging properties. Research on the use of responsive brushes as smart delivery systems is still in its early stages.
ADVANCED HEALTHCARE MATERIALS
(2021)
Article
Polymer Science
Patricia Flemming, Andreas Fery, Petra Uhlmann, Alexander S. Muench
Summary: A robust and efficient grafting method for preparing double thermoresponsive PDMAEMA brushes is proposed for the first time in this study. The synthetic control of grafting density allows for the study of the impact of steric restrictions on thermoresponsive transitions.
Article
Chemistry, Physical
Wenlin Zhang, Lei Zhao, Hui Li, Pantrangi Manasa, Fen Ran
Summary: The new film electrode fabrication technology improves wettability and increases capacitance by introducing halide ions, while achieving a balance between polymer brush grafting on the film surface and pores.
JOURNAL OF POWER SOURCES
(2021)
Article
Chemistry, Physical
Tetiana Shevtsova, Giuseppe Cavallaro, Giuseppe Lazzara, Stefana Milioto, Volodymyr Donchak, Khrystyna Harhay, Sergiy Korolko, Andrzej Budkowski, Yurij Stetsyshyn
Summary: New temperature-responsive hybrid nanomaterials based on modified halloysite nanotubes with grafted polymer brushes containing silver nanoparticles have been successfully fabricated. The introduction of silver nanoparticles significantly reduces the critical solution temperature of the polymer layer. These hybrid nanomaterials have potential applications in solid substrate conservation, production of medical facemasks, and photothermal therapy.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Review
Materials Science, Multidisciplinary
Adnan Murad Bhayo, Yang Yang, Xiangming He
Summary: Polymer brushes are thin films consisting of polymer chains attached to a solid interface by one end. These highly branched polymers exhibit unique characteristics and properties compared to their linear counterparts, making them widely used in fields such as drug delivery and tissue engineering. Surface-initiated controlled radical polymerization has provided a robust method to tailor the chemical and physical properties of surfaces and interfaces, leading to significant innovations in surface and interface engineering.
PROGRESS IN MATERIALS SCIENCE
(2022)
Article
Polymer Science
Koosha Ehtiati, Saeed Z. Moghaddam, Anders E. Daugaard, Esben Thormann
Summary: This study systematically investigated how nonelectrostatic interactions dramatically affect the swelling behavior of polyelectrolyte brushes, revealing fundamentally different swelling behaviors depending on the relative contributions of ion osmotic and nonelectrostatic effects. The results provide new opportunities for applications of polyelectrolyte brushes based on their tunable hydrophobicity and suggest new ideas for fundamental investigations of these systems.
Article
Engineering, Biomedical
Yifeng Ni, Dong Zhang, Shuguang Wang, Jingfeng Yuan, Lingbin Che, Dongyong Sha, Md Fauzul Kabir, Si Yu Zheng, Jun Tan, Jintao Yang
Summary: Bacteria in the external environment invading wounds and colonizing wound surfaces can hinder wound healing and pose a threat to human health. The development of intelligent antibacterial surfaces has significant social and economic importance. This study presents a simple method of creating switchable antibacterial surfaces through ionic interaction-driven activation, with applications in cotton fabrics that promote wound healing and tissue repair.
ACTA BIOMATERIALIA
(2022)
Article
Polymer Science
Guang Chen, Elena Dormidontova
Summary: Polymer-grafted nanopores are widely used in nanotechnological applications. This study investigates the effects of chain length and grafting density on the conformation and hydration of poly(ethylene oxide) grafted to gold nanopores. The results show that if the pore size exceeds the polymer length, increasing the grafting density or chain length leads to conformational changes of the polymer. Moreover, an increase in pore curvature results in polymer crowding within the pore, which affects the effective grafting density.
Article
Multidisciplinary Sciences
Zachary S. Clauss, Casia L. Wardzala, Austin E. Schlirf, Nathaniel S. Wright, Simranpreet S. Saini, Bibiana Onoa, Carlos Bustamante, Jessica R. Kramer
Summary: Researchers successfully synthesized glycopolypeptide brushes with chemically and conformationally tunable properties through one-pot dual-catalysis polymerization of glycan-bearing alpha-amino acid N-carboxyanhydrides. These materials, composed entirely of sugars and amino acids, are non-toxic to cells and degradable by natural proteases, offering new opportunities to examine glycan presentation and multivalency from chemically defined scaffolds.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Sikai Chen, Qing-Yang Feng, Dong Li, Fei Song, Xiu-Li Wang, Yu-Zhong Wang
Summary: This investigation examines the relationship between the structure and properties of surface-grafted cellulose nanofiber (CNF)-based one-component composites. Key parameters, such as graft density, graft chain length, and interface structure, were systematically adjusted. Increasing the graft density and hydrophobic modification of the CNF surface improved thermal stability. Shorter graft chain length increased the T(g) of the graft chain while hydrophobic modification and longer graft chain length decreased stiffness. Decreasing graft density remarkably enhanced toughness and strength. The interfacial interaction between CNF and grafted polymer played a crucial role in determining the composites' properties, along with graft density.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Polymer Science
Flavien Mouillard, Tom Ferte, Emilie Voirin, Stephane Mery, Patrick Masson, Adele Carrado
Summary: The characterization of polymer chains grafted onto substrates is challenging and requires the selective cleavage of chains without polymer degradation for analysis. This study presents a technique for the selective cleavage of PMMA grafted onto titanium substrate using an anchoring molecule combining an ATRP initiator and a UV-cleavable moiety. The technique demonstrates the efficiency of ATRP on titanium substrates and verifies the homogeneous growth of the chains.
Article
Biochemistry & Molecular Biology
Dimitrios Skoulas, Vivien Stuettgen, Rachel Gaul, Sally-Ann Cryan, David J. Brayden, Andreas Heise
Article
Chemistry, Applied
Heliane R. Amaral, James A. Wilson, Ronaldo J. F. C. do Amaral, Irina Pascu, Fernando C. S. de Oliveira, Cathal J. Kearney, Jair C. C. Freitas, Andreas Heise
Summary: This study successfully synthesized bilayer films as cell-free scaffolds to promote keratinocyte attachment and proliferation. The method is eco-friendly and cost-effective, showing potential application in the field of skin tissue engineering.
CARBOHYDRATE POLYMERS
(2021)
Article
Chemistry, Physical
Aoibhin A. Cullen, Ashwene Rajagopal, Katharina Heintz, Andreas Heise, Robert Murphy, Igor Sazanovich, Gregory M. Greetham, Michael Towrie, Conor Long, Deirdre Fitzgerald-Hughes, Mary T. Pryce
Summary: This study reports a neutral BODIPY photosensitizing copolymer with enhanced absorption towards the red and a quantum yield of 0.34 for singlet oxygen generation. The steps leading to the population of the triplet state were studied using time-resolved spectroscopic techniques, showing potential broad-spectrum antimicrobial activity under visible light exposure.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Engineering, Biomedical
Fernando Cabral Sales de Oliveira, Ronaldo Jose Farias Correa do Amaral, Luiza Erthal Cardoso dos Santos, Cian Cummins, Michael M. Morris, Cathal J. Kearney, Andreas Heise
Summary: By attaching amine compound and RGD sequences to the surface of PGl fibers, the functionalized fibers show improved cell adhesiveness and proliferation potential, demonstrating the versatility of PGl in regenerative medicine applications.
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A
(2021)
Article
Pharmacology & Pharmacy
Joanne O'Dwyer, Robert Murphy, Arlyng Gonzalez-Vazquez, Lenka Kovarova, Martin Pravda, Vladimir Velebny, Andreas Heise, Garry P. Duffy, Sally Ann Cryan
Summary: A novel nano-in-gel delivery system (nano-VEGF-HA-TA) for inducing angiogenesis was investigated in this study. The system was successfully injected through a 1.2 m catheter, released VEGF for 42 days, retained bioactivity in vitro, demonstrated promising angiogenic properties in vivo, and is suitable for further clinical translation.
Article
Polymer Science
Bing Wu, Saltuk B. Hanay, Scott D. Kimmins, Sally-Ann Cryan, Daniel Hermida Merino, Andreas Heise
Summary: The ion-induced gelation behavior of statistical copolypeptides comprising lysine and tyrosine is studied, and it is found that the gelation mechanism is related to the formation of stable intermolecular beta-sheet secondary structures induced by the presence of salt ions as well as the aggregation of an alpha-helix between the copolypeptides. The diffusion and mechanical properties of the hydrogels can be tuned by adjusting the polypeptide chain length and ion strength.
Article
Biochemistry & Molecular Biology
Dimitrios Skoulas, Sarinj Fattah, Dandan Wang, Sally-Ann Cryan, Andreas Heise
Summary: 8-arm star polypeptides consisting of cationic polylysine and hydrophilic polysarcosine blocks were synthesized. The enzymatic hydrolysis and disintegration of the polypeptides showed a strong dependence on structural arrangements. The polyplexes formed by the polypeptides were capable of complexing plasmid DNA, had sizes around or below 200 nm, and could transport through mucus.
MACROMOLECULAR BIOSCIENCE
(2022)
Review
Chemistry, Multidisciplinary
Sean O'Halloran, Abhay Pandit, Andreas Heise, Andrew Kellett
Summary: Two-photon polymerization (TPP) is a leading method for microscale fabrication of customized polymeric devices and surfaces. It has a wide range of applications in optics, drug delivery, tissue engineering, and microfluidics. TPP has evolved from standard acrylate- and epoxy-based photoresists to custom formulated monomers that can modify the properties of resulting structures. This article provides an overview of the essential principles and advanced chemical modification strategies for TPP materials and introduces commonly used photoresists and their applications.
Article
Biochemistry & Molecular Biology
Nicola Judge, Panagiotis G. Georgiou, Akalabya Bissoyi, Ashfaq Ahmad, Andreas Heise, Matthew I. Gibson
Summary: Ice-binding proteins (IBPs) are found in extremophile organisms and have various (bio)-technological applications. This study investigates the use of high molecular weight polyproline as an ice recrystallization inhibitor (IRI) and demonstrates the potential of non-vinyl-based polymers in inhibiting ice recrystallization.
Article
Chemistry, Multidisciplinary
Robert D. Murphy, Colm Delaney, Srikanth Kolagatla, Larisa Florea, Craig J. Hawker, Andreas Heise
Summary: This study reports the design of photopolymerizable copolypeptides with tailored mechanical properties for additive manufacturing of 3D objects. The copolypeptides are able to form hydrogels suitable for direct ink writing or direct laser writing, leading to mechanically robust 3D structures.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Polymer Science
Smiljana Stefanovic, Katie McCormick, Sarinj Fattah, Ruiari Brannigan, Sally-Ann Cryan, Andreas Heise
Summary: A new synthetic route was developed to prepare star-shaped poly(l-lysine) from bis-MPA dendrimers. The resulting star polypeptides showed excellent degradability and were able to form polyplexes with nucleic acids for gene delivery.
Article
Polymer Science
Tao Xu, Dimitrios Skoulas, Dawei Ding, Sally-Ann Cryan, Andreas Heise
Summary: In this study, responsive biocompatible nanogels were synthesized for controlled mucosal delivery and release of drugs. The nanogels exhibited suitable size and morphology, and showed responsiveness to reducing agents in the intracellular environment. This work provides a new approach for drug delivery in anti-cancer therapy by overcoming mucosal barriers.
Article
Polymer Science
Nicola Judge, Drazen Pavlovic, Evelin Moldenhauer, Paul Clarke, Ruairi Brannigan, Andreas Heise
Summary: This study demonstrates the preparation of stable hydrophobic polypeptide nanoparticles through miniemulsion polymerization, comprising a poly(l-phenylalanine) and poly(l-leucine) core, as well as two amphiphilic glycosylated block copolypeptide surfactants with hydrophobic blocks. The research reveals a particle size dependence on the surfactant/core combination, with particles being larger if they are identical.
Article
Biochemistry & Molecular Biology
Karmel Sofia Gkika, Anna Kargaard, Christopher S. Burke, Ciaran Dolan, Andreas Heise, Tia E. Keyes
Summary: Oxygen concentration can serve as an effective marker in disease, particularly in cancer, and probes that reflect oxygen levels using ratiometric signals can be applied to conventional methods without specialized equipment. The preparation and in cellulo study of luminescent ratiometric core-shell nanoparticles was demonstrated, showcasing a robust oxygen response and uptake in cancerous cell lines. The co-localisation of ruthenium and BODIPY emission confirmed the particles' integrity with a ratiometric O-2 sensing response in cellulo.
RSC CHEMICAL BIOLOGY
(2021)
Article
Materials Science, Biomaterials
David P. Walsh, Rosanne M. Raftery, Robert Murphy, Gang Chen, Andreas Heise, Fergal J. O'Brien, Sally-Ann Cryan
Summary: Novel star-polypeptide biomaterials carrying two therapeutic genes incorporated into a cell-free scaffold have shown promising results in accelerating bone tissue regeneration, offering a potential solution to clinical challenges such as large bone defects.
BIOMATERIALS SCIENCE
(2021)
