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111.
Fast and Effective Turn‐on Paper‐based Phosphorescence Biosensor for Detection of Glucose in Serum 下载免费PDF全文
Yi‐An Chen Fu‐Ju Tsai Yu‐Ting Zeng Jing‐Chang Wang Chia Ping Hong Pin‐Hsuan Huang Hsiang‐Ling Chuang Shih‐Yao Lin Chu‐Ting Chan Yu‐Chien Ko Yi‐Chieh Chou Tien‐Li Lin Gene‐Hsiang Lee Mei‐Lin Ho 《中国化学会会志》2016,63(5):424-431
In this study, a turn‐on paper‐based optical analytical system with a rapid, sensitive and quantitative response for glucose was developed. The luminescence sensing material, crystalline iridium(III)‐Zn(II) coordination polymers, or Ir‐Zne, was grown electrochemically on stainless steel mesh and then deposited on filter paper. This sensing substrate was subsequently built up under glucose oxidase encapsulated in hydrogel and then immobilized on egg membrane with the layer‐by‐layer method. Once the glucose solution was dropped onto the paper, the oxygen content was depleted simultaneously with a concomitant increase in the phosphorescence of Ir‐Zne. The detection limit for glucose was 0.05 mM. The linear dynamic range for the determination of glucose was 0.05–8.0 mM with a correlation coefficient (R2) of 0.9956 (y=68.11 [glucose]?14.72). The response time was about 0.12 s, and the sample volume was less than 5 μL. The effects of mesh size, buffer concentration, pH, enzyme concentration, temperature, and interference, and the stability of the biosensor, have also been studied in detail. Finally, the biosensor was successfully applied to the determination of glucose in human serum. 相似文献
112.
Biomimetic Taste Receptors with Chiral Recognition by Photoluminescent Metal–Organic Frameworks Chelated with Polyaniline Helices 下载免费PDF全文
Prof. Tu Lee Tsung Yan Lin Hung Lin Lee Yun Hsuan Chang Yee Chen Tsai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1406-1414
The adsorption of phenylaniline (Phe) enantiomers on (+)‐polyaniline (PAN)‐chelated [In(OH)(bdc)]n microcrystals was carefully designed and studied by using the Job titration, circular dichroism, X‐ray photoelectron spectroscopy, and photoluminescence to mimic heterotrimeric guanine nucleotide‐binding protein (G protein)‐coupled receptors in selective, but not specific, ligand binding with chiral recognition and signal transduction. Six essential working principles across different length scales are unraveled: 1) a chiral (+)‐PAN (host), 2) specific sites for Phe‐(+)/PAN (guest–host) binding, 3) a conformational change of (+)‐PAN after binding with Phe enantiomers, 4) different degrees of packing for (+)‐PAN, 5) interactions between (+)‐PAN and the underlying signal‐generating framework (i.e., [In(OH)(bdc)]n microcrystals), and 6) a systematic photoluminescent signal combination by using principal‐component analysis from the other three polymer‐chelated metal–organic frameworkds (MOFs), such as poly(acrylic acid) (PAA), sodium alginate (SA), and polyvinylpyrrolidone (PVP) to enhance the selectivity and discrimination capabilities. 相似文献
113.
Yueh‐Hsuan Tsai Chia‐Her Lin Chu‐Chieh Lin Bao‐Tsan Ko 《Journal of polymer science. Part A, Polymer chemistry》2009,47(19):4927-4936
A novel tridentate anilido‐aldimine ligand, [o‐C6H4(NHAr)? HC?NCH2CH2NMe2] (Ar = 2,6‐iPr2C6H3, L ‐H, 1 ), has been prepared by the condensation of N, N‐dimethylethylenediamine with one molar equivalent of 2‐fluoro‐benzaldehyde in hexane, followed by the addition of the lithium salt of diisopropylaniline in THF. Magnesium (Mg) and zinc (Zn) complexes supported by the tridentate anilido‐aldimine ligand have been synthesized and structurally characterized. Reaction of L ‐H ( 1 ) with an equivalent amount of MgnBu2 or ZnEt2 produces the monomeric complex [ L MgnBu] ( 2 ) or [ L ZnEt] ( 3 ), respectively. Experimental results show that complexes 2 and 3 are efficient catalysts for ring‐opening polymerization of ε‐caprolactone (CL) and L ‐lactide (LA) in the presence of benzyl alcohol and catalyze the polymerization of ε‐CL and L ‐LA in a controlled fashion yielding polymers with a narrow polydispersity index. In both polymerizations, the activity of Mg complex 2 is higher than that of Zn complex 3 , which is probably due to the higher Lewis acidity and better oxophilic nature of Mg2+ metal. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4927–4936, 2009 相似文献
114.
115.
With the assist of a microcomputer interfacing, a bipotentiostat in corporated 4‐electrode detection system was developed as a versatile electrochemical detector for HPLC. An amperometric chromatogram and two three‐dimensional chromatovoltammograms characterizing the electrochemical characteristics of analytes can be obtained in a single chromatographic run. By following the three operation modes developed, both the oxidizable and reducible analytes contained in sample solutions can be determined. The analytical capability of the 4‐electrode detection system was demonstrated by the analysis of solutions containing hydroquinone, catechol and ascorbic acid. From the calibration graphs obtained, linear coefficients better than 0.9992 were found for hydroquinone and catechol in a concentration range of 1.0 × 10?4 to 1.0 × 10?7 M, and a linear coefficient of 0.9929 was found for ascorbic acid in a concentration range of 1.0 × 10?4 to 1.0 × 10?6 M. The detection limits (based on S/N = 3) found were about 1.0 × 10?7 M for hydroquinone and catechol and was 1.0 × 10?6 M for ascorbic acid. 相似文献
116.
Kuan‐Kai Huang Yi‐Kai Fang Jung‐Ching Hsu Chi‐Ching Kuo Wei‐Hsuan Chang Wen‐Chang Chen 《Journal of polymer science. Part A, Polymer chemistry》2011,49(1):147-155
We report the synthesis, micellar structures, and multifunctional sensory properties of new conjugated rod‐coil block copolymers, poly(3‐hexylthiophene)‐block‐poly(2‐(di methylamino)ethylmethacrylate)(P3HT‐b‐PDMAEMA). The new copolymers, synthesized by atom transfer radical polymerization of P3HT macroinitiator, consisted PDMAEMA coil lengths of 43, 65, and 124 repeating units. All the P3HT‐b‐PDMAEMA copolymers exhibit a similar low critical solution temperature in water around 33 °C. The micellar structures of the synthesized polymers were characterized by AFM, TEM, and dynamic light scattering, by varying temperature, pH, and water/THF composition. The micelles of P3HT20‐b‐PDMAEMA43 in water had a reversible size change from 75 ± 5 nm to 132 ± 5 nm on heating from 25 to 55 °C and reduced to the original size during cooling. In addition, the micellar size also showed a significant pH dependence, changing from 67 ± 8 nm (pH = 12) to 222 ± 6 nm (pH = 4), depending on the protonation of the PDMAEMA blocks and their electrostatic repulsion. The micellar structure of three P3HT‐b‐PDMAEMA copolymers changed from spheres, to vesicles, and finally to larger sphere micelles as the solvent composition varied from 0 to 100 wt % water in the mixed solvent. The different micellar structures of P3HT20‐b‐PDMAEMA43 solution led to a red‐shift on the absorption or photoluminescence spectra and exhibited the emission colors of yellow, orange, red, and dark red with increasing the water content. This study suggested that new copolymers had potential applications as multifunctional sensory materials toward temperature, pH, and solvent. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
117.
Chunchi Lin Wei‐Ting Hung Chung‐Hsuan Chen Jim‐Min Fang Wen‐Bin Yang 《Rapid communications in mass spectrometry : RCM》2010,24(1):85-94
A series of saccharides, including maltoheptose, blood type B antigen, pullulan and the glucan of Ganoderma lucidum, are easily converted into the naphthimidazole (NAIM) derivatives in high yields by the iodine‐promoted oxidative condensation. The NAIM‐labeled saccharides, without further purification, show enhanced signals in matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS). The combined use of NAIM derivatization and MALDI‐TOFMS analysis thus provides a rapid method for identification of saccharides even in less than 1 pmol of saccharide in the sample. Characterization of the biologically active saccharides and complex polysaccharides is also achieved through the NAIM‐derivatization method. This study can be further applied to facilitate the isolation and analysis of novel saccharides. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
118.
Min‐Shiun Chao Horng‐Hwa Lu Ming‐Liao Tsai Tsung‐Hsuan Hsieh Chien‐Min Lin 《中国化学会会志》2009,56(5):916-922
The self‐assembly of Co(II) with two diaminodiamide ligands, 4,7‐diazadecanediamide and 4,8‐diazaundecanediamide, gave two different crystals, [(C8H18N4O2)Co(OH)2Co(C8H18N4O2)]Cl2 ( 1 ) [Co(C9H20N4O2)(Cl)(H2O)]·Cl·2H2O ( 2 ). Structures of 1 and 2 were characterized by single‐crystal X‐ray diffraction analysis. Structural data for 1 shows a novel type of binuclear complex with distorted octahederal coordination geometry around the Co atoms through the hydroxo bridges. By using inter‐connector N‐H···N hydrogen bonding interactions as building forces, each cationic moiety [(C8H18N4O2)Co(OH)2Co(C8H18N4O2)]2+ is linked to neighboring ones, producing a charged hydrogen‐bonded 1D chain‐like structure. The chains are further connected into a 2D layer in a (4,4)‐topology via N‐H···Clfree hydrogen‐bonding interactions. Structural data for 2 indicate that the cobalt atom adopts a six‐coordinated N2O4 environment, giving a distorted octahedral geometry, where two N‐ and two O‐donor sets of ligand located at equatorial positions and one water and one chloride occupied at axial positions. Through NH···Cl‐Co and OH···Cl‐Co contacts, each cationic moiety [Co(C9H20N4O2)(Cl)(H2O)]+ in 2 is linked to neighboring ones, producing a charged hydrogen‐bonded 1D chainlike structure. Thus, the crystal‐engineering approach has proved successful in the solid‐state packing due to steric strain effect of the diaminodiamide ligand. 相似文献
119.
Wei‐Ting Sun Yau‐Ting Huang Guan‐Jhih Huang Dr. Hsiu‐Feng Lu Prof. Ito Chao Shou‐Ling Huang Dr. Shing‐Jong Huang Prof. Ying‐Chih Lin Dr. Jinn‐Hsuan Ho Prof. Jye‐Shane Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(38):11594-11604
Five pentiptycene‐derived stilbene systems ( 1 R ; R =H, OM, NO, Pr, and Bu) have been prepared and investigated as light‐driven molecular brakes that have different‐sized brake components ( 1 H < 1 OM < 1 NO < 1 Pr < 1 Bu ). At room temperature (298 K), rotation of the pentiptycene rotor is fast (krot=108–109 s?1) with little interaction with the brake component in the trans form ((E)‐ 1 R ), which corresponds to the brake‐off state. When the brake is turned on by photoisomerization to the cis form ((Z)‐ 1 R ), the pentiptycene rotation can be arrested on the NMR spectroscopic timescale at temperatures that depend on the brake component. In the cases of (Z)‐ 1 NO , (Z)‐ 1 Pr , and (Z)‐ 1 Bu , the rotation is nearly blocked (krot=2–6 s?1) at 298 K. It is also demonstrated that the rotation is slower in [D6]DMSO than in CD2Cl2. A linear relationship between the free energies of the rotational barrier and the steric parameter A values is present only for (Z)‐ 1 H , (Z)‐ 1 OM , and (Z)‐ 1 NO , and it levels off on going from (Z)‐ 1 NO to (Z)‐ 1 Pr and (Z)‐ 1 Bu . DFT calculations provide insights into the substituent effects in the rotational ground and transition states. The molar reversibility of the E–Z photoswitching is up to 46 %, and both the E and Z isomers are stable under the irradiation conditions. 相似文献
120.
The mixed‐valent nickel hexacyanoferrate (NiHCF) and poly(3,4‐ethylenedioxythiophene) (PEDOT) hybrid film (NiHCF‐PEDOT) was prepared on a glassy carbon electrode (GCE) by multiple scan cyclic voltammetry. The films were characterized using atomic force microscopy, field emission scanning electron microscopy, energy dispersive spectroscopy, X‐ray diffraction, and electrochemical impedance spectroscopy (AC impedance). The advantages of these films were demonstrated for the detection of ascorbic acid (AA) using cyclic voltammetry and amperometric techniques. The electrocatalytic oxidation of AA at different electrode surfaces, such as the bare GCE, the NiHCF/GCE, and the NiHCF‐PEDOT/GCE modified electrodes, was determined in phosphate buffer solution (pH 7). The AA electrochemical sensor exhibited a linear response from 5×10−6 to 1.5×10−4 M (R2=0.9973) and from 1.55×10−4 to 3×10−4 M (R2=0.9983), detection limit=1×10−6 M, with a fast response time (3 s) for AA determination. In addition, the NiHCF‐PEDOT/GCE was advantageous in terms of its simple preparation, specificity, stability and reproducibility. 相似文献