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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
Shih-Sheng Sun, Mekonnen Abebayehu Desta, Chia-Wei Liao
A unique strategy for effectively suppressing charge recombination and enhancing light harvesting in dye-sensitized solar cells (DSSCs) is demonstrated by designing a new dipolar organic dye functionalized with a diacetylene unit, which is capable of undergoing photoinduced cross-linking reaction to generate a hydrophobic polydiacetylene layer. The polydiacetylene layer serves as not only an electrolyte-blocking layer to effectively block the approaching of the oxidized redox mediator and supress the dark current but also light-harvesting role by efficient energy transfer to the dipolar dyes...
January 12, 2017: Chemistry, An Asian Journal
Susmita Dolai, Susanta Kumar Bhunia, Stella S Beglaryan, Sofiya Kolusheva, Leila Zeiri, Raz Jelinek
A new hybrid system comprising polydiacetylene (PDA), a chromatic conjugated polymer, embedded within aerogel pores has been constructed. The PDA-aerogel powder underwent dramatic color changes in the presence of volatile organic compounds (VOCs), facilitated through infiltration of the gas molecules into the highly porous aerogel matrix and their interactions with the aerogel-embedded PDA units. The PDA-aerogel composite exhibited rapid color/fluorescence response and enhanced signals upon exposure to low VOC concentrations...
January 25, 2017: ACS Applied Materials & Interfaces
Ting Wang, Yunlong Guo, Pengbo Wan, Xiaoming Sun, Han Zhang, Zhongzhen Yu, Xiaodong Chen
A flexible, transparent, and portable wrist strap sensor device has been well developed from a hierarchical polydiacetylene/MoS2 nanocomposite (PDA/MoS2) film. MoS2 with a nanoflake structure and chelation ability acts as a supporter for PDA films to enhance the porosity as well as the transparency of films, which increases the sensitivity, selectivity, and application potential of a PDA sensor. The PDA/MoS2 film sensor shows a linear detection range for N,N-dimethylformamide (DMF) vapor from 0.01% to 4% with a visible blue to red color change detected by the naked eye, which is more sensitive than other organic vapors...
December 20, 2016: Nanoscale
Defan Yao, Shang Li, Xiaomin Zhu, Junchen Wu, He Tian
Peptide functionalized polydiacetylene (PDA) micelles encapsulated with camptothecin (CPT) kill ovarian cancer cells by the lysosome release of anticancer drug CPT. Moreover, the sub-30 nm PDA micelles penetrate efficiently into a tumor for enhanced therapeutic efficacy.
January 19, 2017: Chemical Communications: Chem Comm
Yueyuan Zhang, Julie Northcutt, Tim Hanks, Ian Miller, Bill Pennington, Raz Jelinek, Inyee Han, Paul Dawson
Polydiacetylene (PDA) vesicles are of interest as biosensors, particularly for pathogenic bacteria. As part of a food monitoring system, interaction with food sanitizers/surfactants was investigated. PDA vesicles were prepared by inkjet-printing, photopolymerized and characterized by dynamic light scattering (DLS) and UV/Vis spectroscopy. The optical response of PDA vesicles at various concentrations verses a fixed sanitizer/surfactant concentration was determined using a two variable factorial design. Sanitizer/surfactant response at various concentrations over time was also measured...
April 15, 2017: Food Chemistry
Mani Ulaganathan, Reinack Varghese Hansen, Nateisha Drayton, Hardik Hingorani, R Govindan Kutty, Hrishikesh Joshi, Sivaramapanicker Sreejith, Zheng Liu, Jinglei Yang, Yanli Zhao
Linear two-dimensional materials have recently attracted an intense interest for supercapacitors because of their potential uses as electrodes in next-generation wearable electronics. However, enhancing the electrochemical properties of these materials without complicated structural modifications remains a challenge. Herein, we present the preparation of a hybrid electrode system via polydiacetylene (PDA) cloaking on the surface of aligned multiwall carbon nanotubes (MWCNTs) through self-assembly based in situ photopolymerization...
December 7, 2016: ACS Applied Materials & Interfaces
Daniela Mazzier, Dario Mosconi, Giulia Marafon, Aikebaier Reheman, Claudio Toniolo, Alessandro Moretto
A symmetrical dipeptide-based diacetylene system (DAs) was found to be able to self-assemble in dichloromethane and to form a compact fiber network which resulted in a stable organogel. As a consequence of the organogel formation, we explored the possibility to run a light-induced topochemical polymerization. This is a typical reaction of ordered diacetylene moieties taking advantage from their organized packing mode resulting from fiber formation. Evidence for the generation of peptide-based polydiacetylenes is provided by Raman, UV-Vis, and CD spectroscopies and a set of microscopic techniques...
November 14, 2016: Journal of Peptide Science: An Official Publication of the European Peptide Society
Woohyun Baek, Jung-Moo Heo, Seungwhan Oh, Sang-Hwa Lee, Jaeyong Kim, Joonyoung F Joung, Sungnam Park, Hesson Chung, Jong-Man Kim
An azobenzene-containing supramolecular polydiacetylene (PDA) crystal undergoes a photoinduced reversible blue-to-red phase transition accompanied by crystal tearing.
November 18, 2016: Chemical Communications: Chem Comm
Baiju P Krishnan, Sreedevi Raghu, Somnath Mukherjee, Kana M Sureshan
An organogelator, 2,4-undeca-diynyl-4',6'-O-benzylidene-β-d-galactopyranoside, which aligns its diacetylene upon gelation, has been synthesized. UV irradiation of its gel resulted in topochemical polymerization of the gelator forming polydiacetylene (PDA). We have used this gel-state reaction for the synthesis of surface-immobilized multi-valent glycoclusters, which showed 1000-fold enhanced binding, compared to monomers, with various galactose-binding lectins.
December 1, 2016: Chemical Communications: Chem Comm
Manoj Kumar Yadav, Vijay Kumar, Bijender Singh, Santosh Kumar Tiwari
The colorimetric assay is phospholipid/polydiacetylene vesicle-based assay used for the detection of membrane-acting peptides. Bacteriocins and halocins are antimicrobial peptides known to kill target cells by membrane disruption. Therefore, the assay was applied for high-throughput (HTP) screening of bacteriocins and halocins produced by lactic acid bacteria and haloarchaea, respectively. The assay consisted of vesicles which were synthesized using four different phospholipids: dipalmitoylphosphatydilcholine (DPPC), dimyristoylphosphatidylcholine (DMPC), dimyristoylphosphoethanolamine (DMPE) and dimyristoylphosphatidylglycerol (DMPG) in combination with diacetylene monomer 10,12-tricosadiy noic acid (TRCDA)...
November 14, 2016: Applied Biochemistry and Biotechnology
Manon Ripoll, Patrick Neuberg, Antoine Kichler, Nassera Tounsi, Alain Wagner, Jean-Serge Remy
A novel generation of pH-responsive photopolymerized diacetylenic amphiphile (PDA) micelles with a diameter of 10 nm was designed and optimized for the intracellular delivery of siRNAs. Dialysis and photopolymerization of the micelles allowed a strong reduction of the cytotoxicity of the nanovector, while the hydrophilic histidine headgroup permitted enhancing the siRNA delivery potential by improving the endosomal escape via imidazole protonation. These PDA-micellar systems were fully characterized by DLS, TEM, and DOSY-NMR experiments...
November 16, 2016: ACS Applied Materials & Interfaces
Jaqueline de Paula Rezende, Guilherme Max Dias Ferreira, Gabriel Max Dias Ferreira, Luis Henrique Mendes da Silva, Maria do Carmo Hepanhol da Silva, Maximiliano Soares Pinto, Ana Clarissa Dos Santos Pires
Bovine serum albumin (BSA) has been recognized as a marker of the cow's health, milk quality, an allergenic protein and as a carrier. Its detection is important in the food, pharmaceutical and medical industries. However, traditional techniques used to detect BSA are often time-consuming, expensive, and show limited sensitivity. This paper describes properties of polydiacetylene-triblock copolymer (L64) nanosensors, synthesized to easily detect BSA. Sensor efficiency was studied as a function of nanosensor composition, polydiacetylene chemical structures, BSA conformation and hydrophobic domain availability, using spectroscopic, calorimetric, light scattering, and electrokinetic analyses...
January 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Chunfeng Chen, Jie Chen, Tianyu Wang, Minghua Liu
Four kinds of commercially available diacetylene (DA) monomers with different chain length, diacetylene positions were fabricated into the organogels via mixing with a chaperone gelator, an amphiphilic l-histidine ester derivative LHC18 that can help the nongelator to form gels. Upon photo irradiation with a 254 nm UV light, the white gels underwent topochemical reaction and turned into red or blue gels, depending on the DA monomer structures. Through the gel formation, the molecular chirality of LHC18 can be transferred to the polydiacetylene (PDA) and helical nanoribbon structures were obtained...
November 9, 2016: ACS Applied Materials & Interfaces
Jasmyn S Abrams, Savannah E Howe, Nathalie Becerra, Punit Kohli, Vjollca Konjufca
In this work, we report a protocol for synthesizing nanosize ovalbumin-functionalized polydiacetylene (PDA) liposomes (LP-Ova). We show that LP-Ova administered per-orally (p.o.) and subcutaneously (s.c.), without the use of adjuvants, induces high serum IgG1 titers. As reported previously using polystyrene nanoparticles (NPs), p.o.-primed mice developed high titers of IgG2c and intestinal IgA following s.c. boosting immunization with LP-Ova. Mice that received a single s.c. immunization with LP-Ova did not develop serum IgG2c or intestinal IgA antibodies...
February 2017: Journal of Biomedical Materials Research. Part A
Dong-En Wang, Lei Zhao, Mao-Sen Yuan, Shu-Wei Chen, Tianbao Li, Jinyi Wang
Polydiacetylene (PDA) materials have been adopted as one of the powerful conjugated polymers for sensing applications due to their unique optical properties. In this paper, we present a new PDA liposome-based sensor system with enhanced fluorescent self-amplification by tuning a fluorophore fluorescence emission. In this system, a 1,8-naphthalimide derivative employed as a highly fluorescent fluorophore was incorporated into a PDA supermolecule. During the formation of blue PDA liposomes, the fluorescence emission of the fluorophore can be directly quenched, while thermal-induced phase transition of PDA liposomes from blue to red can readily restore this fluorescence emission...
October 7, 2016: ACS Applied Materials & Interfaces
Jessica T Wen, Karen Bohorquez, Hideaki Tsutsui
We report a new polydiacetylene (PDA) sensor strip for simple visual detection of zinc ions in aqueous solution. The specificity of this sensor comes from Zn(2+) DNA aptamer probes conjugated onto PDA. Effects of aptamer length and structure on the sensitivity of PDA's color transition were first investigated. PDA conjugated with the optimal aptamer sequence was then coated onto a strip of polyvinylidene fluoride membrane and photopolymerized by UV exposure. The newly developed sensor successfully exhibited a blue-to-red chromatic change in a semi-quantitative manner in response to zinc ions...
September 2016: Sensors and Actuators. B, Chemical
Minjeong Seo, Dong-Hoon Park, Chan Woo Lee, Justyn Jaworski, Jong-Man Kim
Much of atmospheric water originates from transpiration, the process by which plants release H2O from pores, known as stomata, that simultaneously intake CO2 for photosynthesis. Controlling stomatal aperture can regulate the extent of water transport in response to dynamic environmental factors including osmotic stress, temperature, light, and wind. While larger leaf regions are often examined, the extent of water vapor release from individual stomata remains unexplored. Using a "brush-on" sensing material, we can now assess transpiration using a water-responsive, polydiacetylene-based coating on the leaves surfaces...
2016: Scientific Reports
Marina V Makarova, Yuji Okawa, Elisseos Verveniotis, Kenji Watanabe, Takashi Taniguchi, Christian Joachim, Masakazu Aono
The electrical characterization of single-polymer chains on a surface is an important step towards novel molecular device development. The main challenge is the lack of appropriate atomically flat insulating substrates for fabricating single-polymer chains. Here, using atomic force microscopy, we demonstrate that the (0001) surface of an insulating hexagonal boron nitride (h-BN) substrate leads to a flat-lying self-assembled monolayer of diacetylene compounds. The subsequent heating or ultraviolet irradiation can initiate an on-surface polymerization process leading to the formation of long polydiacetylene chains...
September 30, 2016: Nanotechnology
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