Review
Polymer Science
Di Zhou, Liang-Wei Zhu, Bai-Heng Wu, Zhi-Kang Xu, Ling-Shu Wan
Summary: This review comprehensively summarizes the synthetic methods to prepare end-functionalized polymers fabricated by CLRP techniques, including ATRP, RAFT, SFRP, iniferters, ITP, CMRP, and OMRP. The methods basically follow the principles of taking advantage of functional initiators or post-modifying the reactive chain-ends to obtain a wide variety of mono- or di-end-functionalized polymers.
Article
Polymer Science
Keita Fuchise, Kazuhiko Sato, Masayasu Igarashi
Summary: In this study, linear polysiloxanes end-functionalized with disubstituted (Si-C CR) and monosubstituted alkynyl (Si-C CH) groups were successfully synthesized through controlled ring-opening polymerization using water or silanols as initiators, guanidines as catalysts, and alkynyl(amino)silanes as end-capping agents. Various alkynyl-terminated polysiloxanes were obtained, which showed compatibility with non-catalytic and catalytic Huisgen reactions with organoazide compounds. The versatility and orthogonality of the ethynyl groups and the allyl groups for independent modification reactions were demonstrated, providing potential for further functionalization of the polysiloxanes.
Article
Chemistry, Physical
Shengchao Qiu, Hua Xue, Ran Wang, Chi Zhang, Qun He, Guanjun Chang, Weifeng Bu
Summary: Metal-containing polymers have great potential as functional soft materials, but the microphase separation between polymeric segments and metal-ligand complexes has not been well explored. This study focuses on the use of short-chain polystyrenes (PSs) functionalized with nanosized platinum(ii) complexes to control the structures and functions of metal-containing polymers. The results show that by manipulating the polymer length and solvent quality, various self-assembled nanostructures can be formed, and the inside structures of these polymer particles are lamellar with sub-10 nm spacings. This work suggests that metal-containing polymers can self-assemble to form sub-10 nm scale nanostructures with desired properties and functions.
Article
Polymer Science
Paul Strasser, Oliver Plavcan, Edip Ajvazi, Helena Henke, Oliver Bruggemann, Ian Teasdale
Summary: Polyphosphazenes are versatile compounds that can be used for bioconjugation, advanced structure synthesis, and material preparation. We developed a method for synthesizing functionalized polyphosphazenes through end-capping and click reactions. This method can be used to prepare gels based on polyphosphazenes.
JOURNAL OF POLYMER SCIENCE
(2022)
Article
Polymer Science
Xin Wang, Yichen Sun, Xing-Qi Yao, Yan Xu, Jianbo Wang
Summary: In this study, a simple and efficient strategy using diazoacetates as terminating agents was reported to access diverse end-functionalized polymers from a living ring-opening metathesis polymerization process. The chain-end ruthenium carbenes react with diazoacetates to form a C=C bond, leading to the rapid construction of a unique alpha,beta-unsaturated carbonyl motif at more than 95% of the chain end within 5 minutes. Various easily accessible and diversely substituted diazoacetates could be employed to introduce additional useful functionalities at the polymer chain end. Diverse postpolymerization modifications, including Michael addition, click reaction, and chain extension, were also demonstrated.
Article
Polymer Science
Xin Wang, Yichen Sun, Xing-Qi Yao, Yan Xu, Jianbo Wang
Summary: A simple and efficient strategy was developed to access diverse end-functionalized polymers using diazoacetates as a new terminating agent in living ring-opening metathesis polymerization. This strategy allows for the rapid introduction of specific functionalities at the chain end and enables various postpolymerization modifications.
Article
Chemistry, Multidisciplinary
E. Hancox, M. J. Derry, M. J. Greenall, S. Huband, L. Al-Shok, J. S. Town, P. D. Topham, D. M. Haddleton
Summary: Fluoro-poly(acrylic acid) heterotelechelic homopolymers have been synthesized to mimic the ultrafine domains of high chi-low N diblock copolymers. The thermodynamically stable nanomorphologies of lamellar or hexagonally packed cylinders were obtained by heating/cooling ramps. These telechelic homopolymers mimic high chi-ultralow N diblock copolymers and enable reproducible targeting of nanomorphologies with incredibly small, tunable domain size.
Article
Polymer Science
Tuemay Abadi Belay, Jupeng Chen, Huan Xu, Shaowen Zhang, Shilu Chen, Xiaofang Li
Summary: The study presents a method for the synthesis of silane-end-functionalized linear and star polymers through metal-free borates or borane mediated polymerization, with properties easily tunable by varying the type and concentration of hydrosilanes. H-1, Si-29, and H-1-Si-29 HMBC NMR, FT-IR, ESI-MS, and MALDI-TOF-MS analyses confirm the presence of silane-end-functional groups in these polymers, with hydrosilanes playing a dual role in the polymerization process.
Article
Chemistry, Multidisciplinary
Qicheng Liu, Xuan Wang, Jiaqi Liu, Xinyi Zhou, Qingwei Meng, Xinrui Zhou, Dongmei Sun, Yawen Tang
Summary: Research shows that cyanogroup functionalization can enhance the activity of platinum electrocatalysts and reduce the overpotential of the hydrogen evolution reaction. The cyanogroup functionalized Pt ultrafine nanonetworks synthesized by a one-pot heating method have abundant defects and grain boundaries as highly active sites.
Article
Nanoscience & Nanotechnology
Zhihao Wang, Jinping Chen, Tianjun Yu, Yi Zeng, Xudong Guo, Shuangqing Wang, Timothee Allenet, Michaela Vockenhuber, Yasin Ekinci, Guoqiang Yang, Yi Li
Summary: Nonchemically amplified resists based on polystyrene modified with triphenyl sulfonium triflate groups were prepared. The level of sulfonium groups could be controlled by changing the feed ratio of raw materials, resulting in two different resists with sulfonium ratios of 50% and 70%. The PSTS0.7 resist exhibited a better resolution (18 nm half-pitch) compared to the PSTS0.5 resist (20 nm half-pitch) under the same developing conditions for electron beam lithography.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Yahya A. Alzahrani, Masfer H. Alkahtani
Summary: This study successfully achieved the hydrothermal synthesis of small and rounded fluorescent nanodiamonds, which is of significant interest for various applications, particularly in biology. The creation of color centers, specifically nitrogen-vacancy and silicon-vacancy color centers, in the grown nanodiamonds validated the cubic diamond structure. This novel growth technique holds great promise for demanding applications in biology due to its simplicity and ability to grow high-quality diamonds.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Chemistry, Multidisciplinary
Taher Al Najjar, Nageh K. Allam, Ehab N. El Sawy
Summary: In this study, monodispersed polystyrene spheres with an average size of 50 nm were successfully prepared using the emulsion polymerization method. The size and size distribution of the spheres were controlled by optimizing synthesis parameters such as the concentration of monomer, initiator, and surfactant, as well as the type of surfactant and the time and temperature of polymerization. The results indicate that the molar ratio and concentration of monomer and surfactant, along with the polymerization temperature, are the main factors affecting the size of the polystyrene beads.
NANOSCALE ADVANCES
(2021)
Article
Nanoscience & Nanotechnology
Yu Gong, Hongyin Hu, Shaofeng Huang, Shuanglong Lu, Wei Zhang
Summary: In this study, phenylene-ethynylene-based conjugated microporous polymers were synthesized and used as templates for the controlled growth of ultrafine Pd nanoparticles, showing excellent catalytic performance in Suzuki-Miyaura coupling reaction.
ACS APPLIED NANO MATERIALS
(2022)
Article
Crystallography
Jin Motoyanagi, Ayane Fujishima, Masahiko Minoda
Summary: This study investigates a new amphipathic poly(vinyl ether) with an SP moiety, exploring its photoresponsive properties and the control of self-assembly through photoirradiation.
Article
Polymer Science
Jiawei Chen, Wenbing Wang, Yao Pan, Dan Peng, Yougui Li, Chen Zou
Summary: In this study, direct copolymerization of plant oil-based copolymer monomers with ethylene was achieved using a dienyl phosphoribosulfonyl palladium catalyst (PO-Pd). Addition, ureido-pyrimidinone (UPy) functionalization was performed using the hydroxyl group of the polymer. The incorporation of biomass groups effectively modifies the surface and mechanical properties of the copolymers, and these newly developed polymers are ideal tougheners for gutter oil due to their excellent tunability of the self-complementary hydrogen bonding network (UPy).
Article
Chemistry, Multidisciplinary
Zachary J. Urbach, Sarah S. Park, Steven L. Weigand, James E. Rix, Byeongdu Lee, Chad A. Mirkin
Summary: The study demonstrates that in a magnetic field, cubic Fe3O4 nanoparticles functionalized with DNA can exhibit unexpected crystallographic alignment of the entire superlattice, expanding the potential of crystal engineering with DNA through physical and chemical control.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Ho Fung Cheng, Shunzhi Wang, Chad A. Mirkin
Summary: Recent studies have shown that PAEs can behave as electron equivalents at small size and low DNA grafting density, however, the polydispersity in the number of DNA strands on the surfaces of these NPs limits the structural uniformity and tailorability of NP-based EEs. By assembling molecularly precise EEs with complementary NP-based PAEs, three distinct metallic phases can be formed, demonstrating that molecular-based EEs can influence specific phase formation.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Jingshan S. Du, Kun He, Yaobin Xu, Carolin B. Wahl, David D. Xu, Vinayak P. Dravid, Chad A. Mirkin
Summary: The study demonstrates that bimetallic hetero-nanostructures composed of phase-segregated metals undergo galvanic corrosion in aqueous environments, resulting in the formation of stable half-spheroid particles. The two-stage corrosion process of Cu and Ag is observed using in situ scanning transmission electron microscopy, and treating the structures with Ar plasma enhances their stability against corrosion by transforming the native oxide into a denser CuO layer.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
David D. Xu, Carolin B. Wahl, Jingshan S. Du, Shawn Irgen-Gioro, Emily A. Weiss, Chad A. Mirkin
Summary: This method presents a versatile approach for synthesizing Yb3+- and Er3+-doped NaYF4 upconversion nanoparticle arrays by positioning nanoparticles at precisely defined locations through the tip-directed deposition of polyol nanoreactors and subsequent thermal conversion. Single nanoparticles with upconversion properties can be attained by tuning precursor concentration, nanoreactor size, and temperature ramping rate.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Shunzhi Wang, Sangmin Lee, Jingshan S. Du, Benjamin E. Partridge, Ho Fung Cheng, Wenjie Zhou, Vinayak P. Dravid, Byeongdu Lee, Sharon C. Glotzer, Chad A. Mirkin
Summary: This study presents a method to generate complex, low-symmetry colloidal crystals using programmable atom equivalents and mobile electron equivalents. The spatial distribution of the electron equivalents breaks the symmetry of the atom equivalents, resulting in well-defined coordination geometries and three new low-symmetry crystalline phases.
Article
Chemistry, Multidisciplinary
Wuliang Zhang, Cassandra E. Callmann, Brian Meckes, Chad A. Mirkin
Summary: This study presents a strategy to enhance tumor accumulation, prolong blood circulation, and limit non-specific immune activation of nanomaterials through peptide-based, tumor-responsive, sheddable coatings. Spherical nucleic acids (SNAs) with zwitterionic polypeptide shells containing recognition sequences for tumor-associated proteases were designed. The polypeptide coating can be rapidly cleaved in the presence of matrix metalloproteinases (MMPs), increasing cellular uptake of SNAs and shielding them from immune system recognition. This strategy shows potential for the targeted delivery of oligonucleotides and nanomaterials with low immunogenicity.
Article
Chemistry, Multidisciplinary
Jingshan S. Du, Vinayak P. Dravid, Chad A. Mirkin
Summary: A library of well-defined Au-Cu alloy nanocrystals with specific compositions and structures has been created using scanning probe block copolymer lithography, providing a valuable tool for mapping composition and structure space and determining the necessary conditions for accessing specific structures. This approach has led to the discovery of a previously unseen architecture, called an intermetallic nanoprism, that is formed through hierarchical atom stacking. The distinctive diffraction patterns observed in these structures serve as diagnostic indicators. Examination of the library's pseudospherical particles revealed a specific interfacial configuration within the intermetallic nanocrystals. This parallel kinetic-control approach offers a rapid and cost-effective method for exploring complex nanocrystals that could have applications in catalysis and plasmonic sensing.
Article
Chemistry, Multidisciplinary
Donghoon Shin, Minliang Lai, Yongjin Shin, Jingshan S. S. Du, Liban Jibril, James M. Rondinelli, Chad A. Mirkin
Summary: The stability, reliability, and performance of halide-perovskite-based devices are determined by the structure, composition, and particle size of the device-enabling materials. A new method called evaporation-crystallization polymer pen lithography is used to synthesize and study Cs(0.5)FA(0.5)PbX(3) crystals and discover heterostructure morphology. The heterostructures are formed due to differences in solubility of ions and enthalpic preference for ion segregation, and solid-solution nanocrystals are synthesized to suppress photoinduced anion migration for photostable optoelectronic materials.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Millicent Lin, Brian Meckes, Chaojian Chen, Michelle H. Teplensky, Chad A. Mirkin
Summary: The plasma membrane and actomyosin cytoskeleton are crucial in cellular sensing and interaction. This research demonstrates that nanoscopic ligand arrangements can actively regulate cell uptake by controlling actomyosin contractility.
ACS CENTRAL SCIENCE
(2022)
Editorial Material
Chemistry, Multidisciplinary
Jingshan S. Du, Tongkai Chen, Fang Liu, Shengpeng Wang, Jinming Zhang, Ruoyu Zhang
FRONTIERS IN CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Kai Wang, Kun Man, Jiafeng Liu, Brian Meckes, Yong Yang
Summary: Regulating cell behavior using nanotopography is widely used, but the complex effects of physical and biochemical cues hinder our understanding, limiting its biomedical applications. To analyze the individual roles, substrates with different physical nanotopography but identical biochemical nanopatterns and vice versa were fabricated. The results showed physical topographies dominantly control cell spreading, YAP localization, proliferation, and differentiation, while biochemical nanopatterns affect hMSC elongation, YAP intracellular localization, and LAMAC expression. Physical nanogratings induce nanoscale curvature of nuclei, attenuating osteogenic differentiation of hMSCs. Fine-tuning cell behavior is possible by altering the presentation of biochemical cues on substrate surfaces.
Article
Chemistry, Physical
Katelyn Mathis, Afia Ibnat Kohon, Stephen Black, Brian Meckes
Summary: The interactions between heterogeneous cell populations play important roles in dictating various cell behaviors. Current methods, such as 3D cell-printing, have difficulty achieving precise control over heterojunctions formed between cells. This article presents a technique combining DNA-mediated cell interactions with cell-compatible photolithographic approaches to control cell assembly. By coating cells with oligonucleotides containing DNA nucleobases and using photocleavable moieties, light-controlled cell assembly was achieved. This technique, combined with digital micromirror devices, allows for selective activation of specific cell populations, opening new pathways for on-demand programming of complex cell structures.
Article
Nanoscience & Nanotechnology
Kun Man, Jiafeng Liu, Cindy Liang, Christopher Corona, Michael D. Story, Brian Meckes, Yong Yang
Summary: Determining the mechanistic causes of lung diseases and developing new treatments would benefit from a clinically relevant preclinical human lung alveolar interstitium model. Existing models fail to replicate the key physiological characteristics of human alveoli. A human lung alveolar interstitium chip was developed to imitate the microenvironmental factors of alveoli and showed improved epithelial barrier function compared to transwell models. The chip sustained interstitial integrity and enhanced the epithelial barrier, resulting in a longevity that extended beyond eight weeks. The chip also provided accurate assessment of multiwalled carbon nanotube toxicity.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Wenjie Zhou, Yein Lim, Haixin Lin, Sangmin Lee, Yuanwei Li, Ziyin Huang, Jingshan S. Du, Byeongdu Lee, Shunzhi Wang, Ana Sanchez-Iglesias, Marek Grzelczak, Luis M. Liz-Marzan, Sharon C. Glotzer, Chad A. Mirkin
Summary: This study successfully assembled colloidal quasicrystals by exploiting the geometry of nanoscale decahedra and the programmable bonding characteristics of DNA immobilized on their facets. The process is enthalpy-driven, works over a range of particle sizes and DNA lengths, and is made possible by the energetic preference of the system to maximize DNA duplex formation and favor facet alignment. The resulting colloidal quasicrystals exhibit specific structures with stacking disorder providing thermodynamic stability.
Article
Engineering, Biomedical
EunBi Oh, Brian Meckes, Jinyoung Chang, Donghoon Shin, Chad A. Mirkin
Summary: The size and spatial arrangement of hard and soft domains have a significant impact on cancer cell migration speed, with the maximum observed speed on hydrogels with specific pattern sizes and spacings. The study of cell-ECM interactions at the interface of hard and soft domains provides insights into how cancer cells interact with their environment.
ADVANCED NANOBIOMED RESEARCH
(2022)