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Do Hyun Kang, Ho-Sup Jung, Keesung Kim, Jinsang Kim
Most solid-state biosensor platforms require a specific immobilization chemistry and a bioconjugation strategy separately to tether sensory molecules to a substrate and attach specific receptors to the sensory unit, respectively. We developed a mussel-inspired universal conjugation method that enables both surface immobilization and bioconjugation at the same time. By incorporating dopamine or catechol moiety into self-signaling polydiacetylene (PDA) liposomes, we demonstrated efficient immobilization of the PDA liposomes to a wide range of substrates, without any substrate modification...
November 17, 2017: ACS Applied Materials & Interfaces
Robert S Jordan, Yolanda L Li, Cheng-Wei Lin, Ryan D McCurdy, Janice B Lin, Jonathan L Brosmer, Kristofer L Marsh, Saeed I Khan, K N Houk, Richard B Kaner, Yves Rubin
We demonstrate a highly efficient thermal conversion of four differently substituted polydiacetylenes (PDAs 1 and 2a-c) into virtually indistinguishable N = 8 armchair graphene nanoribbons ([8]AGNR). PDAs 1 and 2a-c are themselves easily accessed through photochemically initiated topochemical polymerization of diynes 3 and 4a-c in the crystal. The clean, quantitative transformation of PDAs 1 and 2a-c into [8]AGNR occurs via a series of Hopf pericyclic reactions, followed by aromatization reactions of the annulated polycyclic aromatic intermediates, as well as homolytic bond fragmentation of the edge functional groups upon heating up to 600 °C under an inert atmosphere...
November 8, 2017: Journal of the American Chemical Society
Najmeh Moazeni, Masoud Latifi, Ali Akbar Merati, Shohre Rouhani
In this study, polydiacetylene (PDA) is embedded in electrospun polyvinylidene fluoride (PVDF) nanofibers for the preparation of mats with dual colorimetric and piezoelectric responses. The diacetylene monomers are self-assembled during the electrospinning process. The PDA-embedded PVDF nanofibers in the blue phase are obtained via photo-polymerization upon UV-light irradiation. The colorimetric transition of the nanofibers is studied as a function of temperature using a spectrophotometer. The morphology and crystal polymorphism of the nanofibers are investigated...
November 15, 2017: Soft Matter
Shuai Li, Li Zhang, Jian Jiang, Yan Meng, Minghua Liu
An l-glutamic acid terminated amphiphilic diacetylene was designed and found to self-assemble into vesicles in water and supramolecular gel with helical structures in mixed methanol/water solvent. Both the vesicles and the helices underwent topochemical photopolymerization under UV irradiation and changed to a blue color. During the self-assembly and photopolymerization, the chirality of localized l-glutamic acid was successfully transferred to polydiacetylene (PDA), which resulted in obvious CD signals in the PDA blue phase...
October 12, 2017: ACS Applied Materials & Interfaces
Gabriel Max Dias Ferreira, Guilherme Max Dias Ferreira, Maria do Carmo Hespanhol, Jaqueline de Paula Rezende, Ana Clarissa Dos Santos Pires, Paulo Fernando Ribeiro Ortega, Luis Henrique Mendes da Silva
Polydiacetylene (PDA) vesicles have been applied as optical sensors in different areas, although there are difficulties in controlling their responses. In this study, we prepared nanoblends of PDA with triblock copolymers (TC) as a better sensor system for detecting temperature change. The influences of diacetylene (DA) monomer, and the TC chemical structure and concentration on the colorimetric response (CR) were examined. The TC/PDA nanoblend was remarkably more sensitive to temperature change, than classical vesicles...
February 15, 2018: Food Chemistry
Gonzalo García-Espejo, Marta Pérez-Morales, Michel Goldmann, María T Martín-Romero, Juan J Giner-Casares, Luis Camacho
Mixed Langmuir monolayers of 10,12-Pentacosadiynoic acid (DA) monomer and an amphiphilic Hemicyanine dye derivative have been formed at the air/water interface. Two derivatives of docosylpyridinium have been used, with either one included in the monolayer in 1:1molar ratio. The DA monomers within the mixed monolayers have been polymerized in situ at the air/water interface. The crystalline structure of the monolayer and the kinetics of polymerization have been probed by grazing incidence X-ray diffraction (GIXD)...
August 22, 2017: Journal of Colloid and Interface Science
Ying Wang, Hanwen Pei, Yan Jia, Jianhua Liu, Zelun Li, Kelong Ai, Zhongyuan Lu, Lehui Lu
Early detection of ovarian cancer, the most lethal type of gynecologic cancer, can dramatically improve the efficacy of available treatment strategies. However, few screening tools exist for rapidly and effectively diagnosing ovarian cancer in early stages. Here, we present a facile "lock-key" strategy, based on rapid, specific detection of plasma lysophosphatidic acid (LPA, an early stage biomarker) with polydiacetylenes (PDAs)-based probe, for the early diagnosis of ovarian cancer. This strategy relies on specifically inserting LPA "key" into the PDAs "lock" through the synergistic electrostatic and hydrophobic interactions between them, leading to conformation transition of the PDA backbone with a concomitant blue-to-red color change...
August 14, 2017: Journal of the American Chemical Society
Jinkyu Roh, Su Yeon Lee, Sangho Park, Dong June Ahn
The immunochromatographic assay (ICA) using a nitrocellulose (NC) membrane offers several advantages. This technique is a rapid and straightforward method in contrast to other immunoassays. Polydiacetylene (PDA) vesicles have unique optical properties, displaying red color and red fluorescence at the same time. In this system, red-phase PDA vesicles are used as a fluorescent dye as well as a surface for immobilized hepatitis B surface antibody (HBsAb). PDA has a remarkable stability compared with other fluorescent dyes...
August 17, 2017: Chemistry, An Asian Journal
P Maffert, S Reverchon, W Nasser, C Rozand, H Abaibou
Point-of-care diagnosis based on nucleic acid testing aims to incorporate all the analytical steps, from sample preparation to nucleic acid amplification and detection, in a single device. This device needs to provide a low-cost, robust, sensitive, specific, and easily readable analysis. Microfluidics has great potential for handling small volumes of fluids on a single platform. Microfluidic technology has recently been applied to paper, which is already used in low-cost lateral flow tests. Nucleic acid extraction from a biological specimen usually requires cell filtration and lysis on specific membranes, while affinity matrices, such as chitosan or polydiacetylene, are well suited to concentrating nucleic acids for subsequent amplification...
October 2017: European Journal of Clinical Microbiology & Infectious Diseases
Marcos Fernandez-Castano Romera, René P M Lafleur, Clément Guibert, Ilja K Voets, Cornelis Storm, Rint P Sijbesma
Biomimetic, strain-stiffening materials are reported, made through self-assembly and covalent fixation of small building blocks to form fibrous hydrogels that are able to stiffen by an order of magnitude in response to applied stress. The gels consist of semi-flexible rodlike micelles of bisurea bolaamphiphiles with oligo(ethylene oxide) (EO) outer blocks and a polydiacetylene (PDA) backbone. The micelles are fibers, composed of 9-10 ribbons. A gelation method based on Cu-catalyzed azide-alkyne cycloaddition (CuAAC), was developed and shown to lead to strain-stiffening hydrogels with unusual, yet universal, linear and nonlinear stress-strain response...
July 17, 2017: Angewandte Chemie
Yukiko Ishijima, Mamoru Okaniwa, Yuya Oaki, Hiroaki Imai
Nanosheets have attracted much interest because of their characteristic properties originating from anisotropic and flexible structures. Inorganic nanosheets are synthesized from precursor layered compounds through exfoliation in a liquid phase. In contrast, a versatile exfoliation approach has not been fully studied for organic layered compounds. Here we report two exfoliation approaches for organic layered compounds. Hydrophilic and hydrophobic polydiacetylene (PDA) nanosheets, around 5 nm in thickness, are obtained through exfoliation of the layered precursor in aqueous and nonpolar organic media, respectively...
January 1, 2017: Chemical Science
Machi Takeuchi, Hiroaki Imai, Yuya Oaki
Organic layered materials have intercalation and dynamic properties. The dynamic properties are tuned by the intercalation of the guests. In general, however, it is not easy to achieve the homogeneous and thin coating of the layered materials on substrates with complex shapes because of the two-dimensional anisotropic structures. In the present work, the layered organic composites were homogeneously coated on a variety of substrates for application to practical devices. The metal-ion-intercalated layered polydiacetylene (PDA-M(n+)) with tunable stimuli-responsive color-change properties was coated on substrates, such as paper and cotton consisting of cellulose fibers...
May 3, 2017: ACS Applied Materials & Interfaces
Ming Li, Mengyao Song, Guitai Wu, Zhenyu Tang, Yunfeng Sun, Yunbin He, Jinhua Li, Lei Li, Haoshuang Gu, Xiong Liu, Chuang Ma, Zefei Peng, Zhaoquan Ai, David J Lewis
In many 2D materials reported thus far, the forces confining atoms in a 2D plane are often strong interactions, such as covalent bonding. Herein, the first demonstration that hydrogen (H)-bonding can be utilized to assemble polydiacetylene (a conductive polymer) toward a 2D material, which is stable enough to be free-standing, is shown. The 2D material is well characterized by a large number of techniques (mainly different microscopy techniques). The H-bonding allows splitting of the material into ribbons, which can reassemble, similar to a zipper, leading to the first example of a healable 2D material...
June 2017: Small
Jessica T Wen, Polrit Viravathana, Brian Ingel, Caroline Roper, Hideaki Tsutsui
This study presents a sensor strip for user-friendly, naked-eye detection of Xylella fasitdiosa, the bacterial causal agent of Pierce's disease in grapevine. This sensor uses anti- X. fastidiosa antibodies conjugated to a polydiacetylene layer on a polyvinylidene fluoride strip to generate specific color transitions and discriminate levels of the pathogen. The detection limit of the sensor is 0.8 × 10(8) cells/mL, which is similar to bacterial load in grapevine 18 days following bacterial inoculation. This sensor enables equipment-free detection that is highly desirable for in-field diagnostic tools in resource-limited settings...
August 2017: SLAS Technology
Maarten B Callens, Wouter Crijns, Tom Depuydt, Karin Haustermans, Frederik Maes, Emiliano D'Agostino, Martine Wevers, Helge Pfeiffer, Koen Van Den Abeele
PURPOSE: The aim of this work was to model the dose dependence of the darkening of GafChromic™ EBT3 films by combining the optical properties of the polydiacetylene polymer phases, and a modified version of the single-hit model, which will take the stick-like shape of the monomer microcrystals into account. Second, a comparison is made between the quantification of the film darkening by flatbed scanning and by UV-vis absorption spectroscopy. METHOD: GafChromic(TM) EBT3 films were irradiated with a 6 MV photon beam at dose levels between 0 and 50 Gy...
March 30, 2017: Medical Physics
Wenjie Dong, Guanhua Lin, Haifei Wang, Wensheng Lu
Thermal responsive polydiacetylene derived from PAMAM dendrimer (PDA-G0) was synthesized. Unlike the ethylenediamine substituted PDA (PDA-NH2) solution, the prepared PDA-G0 vesicle solution showed reversible thermochromism property when temperature varied from 20 to 90 °C, which is due to the formation of an internal hydrogen bond in amide groups. Furthermore, PDA-G0/PMMA film with excellent stability was obtained by a mixed-drying method, which could be stored for a long time without denaturation. After polymerization by UV irradiation, it displayed much better reversible thermochromic ability and the responded temperature range became wider, from 20 to 110 °C...
March 23, 2017: ACS Applied Materials & Interfaces
Lander Verstraete, Brandon E Hirsch, John Greenwood, Steven De Feyter
Polydiacetylene polymers of defined lengths are formed from self-assembled precursors inside nanocorrals created within grafted graphite substrates. A scanning tunneling microscope tip is used to nanoshave corrals at the liquid-solid interface allowing orientationally controlled supramolecular self-assembly of linear diacetylene molecules. Electrical pulses trigger topological one-dimensional polymerization reactions that are confined by the nanocorral template dimensions.
April 11, 2017: Chemical Communications: Chem Comm
Roberto Diego Ortuso, Ugo Cataldi, Kaori Sugihara
We have demonstrated colorimetric and fluorescence detection of a peptide, melittin, based on polydiacetylene (PDA) made of 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC(8,9)PC). The PDA used in this work has a phosphocholine headgroup, which mimics peptide-cell membrane interactions better than the conventional PDAs with carboxyl headgroups. The dose curve (colorimetric response vs. melittin concentration) showed a half maximum response at the melittin concentration of 0.1 mg ml(-1), which is similar to that reported in traditional PDA assays...
February 6, 2017: Soft Matter
Sylvie Spagnoli, Emrick Briand, Ian Vickridge, Jean-Louis Fave, Michel Schott
The absorptivities of polydiacetylenes (PDAs) used in Langmuir films or vesicles for the development of PDA sensor films or other applications such as nonlinear optics and field-effect transistors are not known, so the polymer contents cannot be deduced from experimental spectra. Here we introduce a novel method, using nuclear reaction analysis (NRA), that allows a quantitative determination of the polymer content X proportion of monomers that have been incorporated into PDA chains. We apply it to pentacosadiynoic acid (PCDA) evaporated microcrystalline films...
January 31, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Mekonnen Abebayehu Desta, Chia-Wei Liao, Shih-Sheng Sun
A unique strategy to suppress charge recombination effectively and enhance light harvesting in dye-sensitized solar cells (DSSCs) is demonstrated by the design of a new dipolar organic dye functionalized with a diacetylene unit, which is capable of undergoing a photoinduced crosslinking reaction to generate a hydrophobic polydiacetylene layer. The polydiacetylene layer serves as an electrolyte-blocking layer that effectively blocks the approach of the oxidized redox mediator and suppresses the dark current, and also plays a role in light harvesting owing to efficient energy transfer to the dipolar dyes...
January 12, 2017: Chemistry, An Asian Journal
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