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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 photo-polymerization 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 2, 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 non-gelator to form gels. Upon photo irradiation with a 254 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...
October 19, 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 nano-size 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. In contrast, mice that received a single s.c. immunization with LP-Ova did not develop serum IgG2c or intestinal IgA antibodies...
October 17, 2016: 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
Eunae Cho, Hwanhee Kim, Youngjin Choi, Seung R Paik, Seunho Jung
Selective visualization of arginine and lysine has been explored among 20 amino acids using the hybrid conjugate of β-cyclodextrin (β-CD) and polydiacetylene (PDA). The mono pentacosa-10,12-diynyl aminomethyl group was successfully coupled to either the primary or the secondary face of β-CD, where mono-6-amino-6-deoxy-β-CD or mono-3-amino-3-deoxy-β-CD reacted with the N-hydroxysuccinimide ester of 10,12-pentacosadiynoic acid. In this combinatorial system, the cylindrical β-cyclodextrin functions as a channel for the introduction of the cationic amino acids to the artificial membrane...
2016: Scientific Reports
Joonyoung F Joung, Junwoo Baek, Youngseo Kim, Songyi Lee, Myung Hwa Kim, Juyoung Yoon, Sungnam Park
Photo-curable polymers originating from 10,12-pentacosadiynoic acid (PCDA-PDA) are commonly used polydiacetylenes (PDAs). PCDA-PDA exhibits thermochromic properties undergoing a unique colorimetric transition from blue to red as the temperature is increased from low to high. In this work, we have carefully studied the temperature-dependent optical properties of PCDA-PDA by using UV-visible absorption, FTIR, Raman, and transient absorption (TA) spectroscopy in combination with quantum chemical calculations. Temperature-dependent UV-visible absorption spectra indicate that PCDA-PDA exhibits reversible thermochromic properties up to 60 °C and its thermochromic properties become irreversible above 60 °C...
August 17, 2016: Physical Chemistry Chemical Physics: PCCP
Takaaki Manaka, Mitsumasa Iwamoto
Asymmetric polymerization of polydiacetylene (PDA) from commercially available achiral derivative of diacetylene monomer using circularly polarized pulse laser is demonstrated. Chiral source was only circularly polarized laser, and irradiation of left- and right-circularly polarized light effectively promoted the polymerization of chiral PDAs with opposite handedness. Difference between the laser wavelength and the absorption peak of monomer suggested the contribution of the multiphoton excitation to the photo-polymerization...
April 2016: Journal of Nanoscience and Nanotechnology
Jimin Park, Seul Kathy Ku, Deokwon Seo, Kahyun Hur, Hojeong Jeon, Dmitry Shvartsman, Hyun-Kwang Seok, David J Mooney, Kangwon Lee
Polydiacetylene (PDA) liposomes were prepared to selectively capture target released from bacteria. Specific interplay between released-surfactin and PDA resulted in a conformal change in the structure of PDA, highlighting the potential of indirect interactions between bacteria and PDA in the construction of new label-free bacterial sensors.
August 16, 2016: Chemical Communications: Chem Comm
Min-Cheol Lim, Young-Rok Kim
The detection of food pathogens is an important aspect of food safety. A range of detection systems and new analytical materials have been developed to achieve fast, sensitive, and accurate monitoring of target pathogens. In this review, we summarize the characteristics of selected nanomaterials and their applications in food, and place focus on the monitoring of biological and chemical contaminants in food. The unique optical and electrical properties of nanomaterials, such as gold nanoparticles, nanorods, quantum dots, carbon nanotubes, graphenes, nanopores, and polydiacetylene nanovesicles, are closely associated with their dimensions, which are comparable in scale to those of targeted biomolecules...
September 28, 2016: Journal of Microbiology and Biotechnology
M Belén Oviedo, Niranjan V Ilawe, Bryan M Wong
We present a detailed analysis of nonempirically tuned range-separated functionals, with both short- and long-range exchange, for calculating the static linear polarizability and second hyperpolarizabilities of various polydiacetylene (PDA) and polybutatriene (PBT) oligomers. Contrary to previous work on these systems, we find that the inclusion of some amount of short-range exchange does improve the accuracy of the computed polarizabilities and second hyperpolarizabilities. Most importantly, in contrast to prior studies on these oligomers, we find that the lowest-energy electronic states for PBT are not closed-shell singlets, and enhanced accuracy with range-separated DFT can be obtained by allowing the system to relax to a lower-energy broken-symmetry solution...
August 9, 2016: Journal of Chemical Theory and Computation
Songyi Lee, Ji-Yeong Kim, Xiaoqiang Chen, Juyoung Yoon
Polydiacetylenes (PDAs) have received increasing attention as smart materials owing to their unique properties. Upon addition of various stimuli, blue PDAs can undergo a colorimetric transition from blue to red along with a change from non-fluorescent to fluorescent. The optical changes can be readily detected by the naked eye and by using absorption and fluorescence spectrometers. These properties make PDAs excellent materials for use in platforms for sensing chemical or biological targets. In recent years, a number of biosensors and chemosensors based on the optical responses of polydiacetylenes have been reported...
July 28, 2016: Chemical Communications: Chem Comm
Yun Kyung Jung, Cheulhee Jung, Hyun Gyu Park
We describe a novel strategy to fabricate a well-defined polydiacetylene (PDA) supramolecular pattern on polyvinylidene fluoride (PVDF) membrane utilizing a DNA bio-photomask. By focusing on that, the absorption spectrum of DNA molecules having a λmax at 260 nm overlaps with the wavelength at which the photopolymerization of the diacetylene monomer occurs, DNA molecules are used to define specific patterns on PVDF membranes coated with diacetylene lipids by shielding the applied 254 nm UV light and consequently preventing the photopolymerization of the lipids...
June 22, 2016: ACS Applied Materials & Interfaces
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