Read by QxMD icon Read


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
Yu Zhu, Dong Qiu, Guang Yang, Mengqiao Wang, Qijin Zhang, Pei Wang, Hai Ming, Douguo Zhang, Yue Yu, Gang Zou, Ramachandram Badugu, Joseph R Lakowicz
Development of rapid, highly selective and sensitive miRNA detection in a complex biological environment has attracted considerable attention. Herein, we describe a novel two step method to construct gold-nanorod functionalized polydiacetylene (PDA) microtube for miRNA detection. In PDA microtube, with a one-dimensional (1D) waveguide nature, the excitation position and emission out-coupling position are far apart, thus helpful in reducing contribution of auto-fluorescence from biological sample. The use of specially designed toehold-mediated strand displacement reaction enables the reliable and selective discrimination of miRNA sequences with high sequence homology...
November 15, 2016: Biosensors & Bioelectronics
Dong-Hoon Park, Bum Jun Park, Jong-Man Kim
Hydrochromic materials, which undergo changes in their light absorption and/or emission properties in response to water, have been extensively investigated as humidity sensors. Recent advances in the design of these materials have led to novel applications, including monitoring the water content of organic solvents, water-jet-based rewritable printing on paper, and hydrochromic mapping of human sweat pores. Our interest in this area has focused on the design of hydrochromic materials for human sweat pore mapping...
June 21, 2016: Accounts of Chemical Research
Ryoko Yamamoto, Shigehiko Takegami, Atsuko Konishi, Hikari Horikawa, Sayumi Yonezawa, Tatsuya Kitade
In this study, a polydiacetylene liposomal aequorin bioluminescent device (PLABD) that functioned through control of the membrane transport of Ca(2+) ions was developed for detecting hydrophobic compounds. In the PLABD, aequorin was encapsulated in an internal water phase and a calcium ionophore (CI) was contained in a hydrophobic region. Membrane transport of Ca(2+) ions across the CI was suppressed by polymerization between diacetylene molecules. On addition of an analyte, the membrane transport of Ca(2+) ions across the CI increased, and Ca(2+) ions from the external water phase could diffuse into the internal water phase via the CI, which resulted in bioluminescence of the aequorin...
June 7, 2016: Analytical Chemistry
Hongyan Xia, Ruxue Wang, Yingying Liu, Junjie Cheng, Gang Zou, Qijin Zhang, Douguo Zhang, Pei Wang, Hai Ming, Ramachandram Badugu, Joseph R Lakowicz
Controlled Polarization Sensitivity of an active polymer microfiber has been proposed and realized with the electrospun method. The fluorescence intensity guiding through this active polymer microfiber shows high sensitivity to the polarization state of the excitation light. What is more, the fluorescence out-coupled from tip of the microfiber can be of designed polarization state. Principle of these phenomena lies on the ordered and controlled orientation of the polydiacetylene (PDA) main chains inside polymer microfiber...
March 2016: Advanced Optical Materials
Hao Jiang, Guy Hershtig, Shachar Richter, Raz Jelinek
We prepared a solution-processed film comprising a drop-casted mixture of melamine-diacetylene and perylene bis(dicarboximide) (PDI). We show that the diacetylene monomers adopt distinct crystalline organization in the presence of the PDI residues. Importantly, the drop-casted diacetylene/PDI film exhibits ultraviolet light-induced conductivity, ascribed to effective transport of charge carriers in the conjugated polymerized network.
May 5, 2016: Journal of Physical Chemistry Letters
Clement Girard-Reydet, Roberto Diego Ortuso, Maria Tsemperouli, Kaori Sugihara
Polydiacetylene (PDA) is a conductive polymer that has mechanochromism. When the polymer is exposed to mechanical stresses, change in temperature (thermochromism), pH (ionochromism), and so forth, the structural perturbation can be seen by the change in its color. Although it presents interesting electrical and optical properties, the relationship between these signals has rarely been investigated. We studied the correlation between the electrical conductivity and the absorption spectra of PDA. Upon UV irradiation, PDA absorption spectra presented a blue shift, which coincided with the decrease in the electrical conductivity...
April 14, 2016: Journal of Physical Chemistry. B
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"