Analytical Sciences
Online ISSN : 1348-2246
Print ISSN : 0910-6340
ISSN-L : 0910-6340
25 巻, 9 号
選択された号の論文の22件中1~22を表示しています
Rapid Communications
Reviews
  • Sunao YAMADA
    原稿種別: Reviews
    2009 年 25 巻 9 号 p. 1059-1068
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    Spectroscopic measurements and applications to analytical sciences utilizing strong interactions between photons and molecules will be described. In particular, this report demonstrates high-sensitivity analysis of chemical species in solution through laser multiphoton ionization, and selective detection and characterization of the molecules located at solid surfaces and phase boundaries by using the method of second harmonic generation. Furthermore, new spectroscopic methods and sensitivity improvements utilizing the resonance of incident light photons with surface plasmons emerging on the surfaces of gold nanoparticles and nanostructures are presented. In addition, applications of surface plasmon resonance to spatio-selective plating to microscopic sites and to the field of nanobiotechnology are described, with special focusing on controlling biomolecules.
Original Papers
  • Takayoshi KAWASAKI, Tetsuhiro MOCHIDA, Jun-ichi KATADA, Yoshio OKAHATA
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1069-1075
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    A weak laser irradiation (523 − 785 nm, 5 − 60 mW) onto an Au electrode surface of a 27-MHz quartz crystal microbalance (QCM) caused a frequency increase (a mass decrease) in the air phase. These frequency changes depended on the wavelength of the irradiated laser in the order of 523 nm > 636 nm > 785 nm, which corresponds to the light absorbance of the Au electrode of the QCM. The laser response increased linearly with increasing laser power (5 − 60 mW). In addition, the laser response showed a maximum at the incidence angle of 72 degrees when the P-polarized 636 nm laser was irradiated on the Au surface, due to the evanescent effect. These laser responses were also observed in the humid air of H2O, D2O, and in the vapors of various alcohols. Based on these findings, the observed frequency increase (mass decrease) can be explained by the photo-induced reversible desorption of water molecules from the Au electrode surface of the QCM due to the interfacial property changes.
  • Hajime KATANO, Kohei UEMATSU, Takao HIBI, Tokuji IKEDA, Toshihide TSUK ...
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1077-1081
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    It has been shown that polyammonium cations comprising quaternary ammonium and hydrophilic groups such as amide and hydroxyl groups stabilize a redox enzyme bilirubin oxidase (BOD). The BOD catalyzes the reaction: 4[Fe(CN)6]4− + 4H+ + O2 → 4[Fe(CN)6]3− + 2H2O, and has been a promising enzyme for use as a cathode catalyst in biofuel cells. In this study, the stabilizing effect of poly[oxyethylene(dimethylimino)propyl(dimethylimino)ethylene] (PA1) on BOD has been investigated. The sample solution containing BOD and the PA1 salt was kept at a given temperature, and the loss of the enzymatic activity was detected after given stored times. The activity decreased exponentially with stored time so that the first-order rate-constant of inactivation was determined. The inactivation rate-constant lowered with increasing the concentration of the PA1 salt, suggesting that BOD was stabilized by the association with the PA1 cation. The PA1 cation may act like a protective colloid or decrease the local disorder of BOD by its wrapping. A membrane-covered electrode containing BOD, PA1, and [Fe(CN)6]4−/3− in the internal solution phase was examined in air-saturated aqueous solution. The electrode gave a well-defined current-potential curve with a steady state limiting current due to the PA1-[Fe(CN)6]4−/3− polyion complex-mediated bioelectrocatalytic current for the reduction of O2. The decreasing of the steady state limiting current became slower in the presence of the PA1 salt, indicating again the stabilizing effect of PA1 cation on BOD.
  • Jianwen ZHAO, Jinfang ZHI, Yanli ZHOU, Wenbin YAN
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1083-1088
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    An amperometric biosensor was constructed by using ZnO nanorod clusters as platforms for immobilizing tyrosinase on the nanocrystalline diamond (NCD) electrodes. The results showed that ZnO nanorod clusters provided an advantageous microenvironment due to their favorable isoelectric point (IEP) for tyrosinase loading; immobilized tyrosinase generally retained its activity. The tyrosinase/ZnO/NCD electrode showed a linear response range of 1 − 210 and sensitivity of 179.9 μA mmol−1 cm−2 for p-cresol. The corresponding values were 1 − 190 and 90.2 for phenol, and 1 − 250 and 121.3 for 4-chlorophenol. The low detection limits were estimated to be 0.2 μM for p-cresol, 0.5 μM for phenol, and 0.4 μM for 4-chlorophenol (S/N = 3). The prepared enzyme electrode could keep 85% of its original activity after intermittent use for 4 weeks when stored in a dry state at 277 K. Therefore, the ZnO nanorod cluster thin films have potential applications as platforms to immobilize other enzymes and bioactive molecules in biosensors.
  • Liuduan YAO, Youwen TANG, Weipeng ZENG, Zhaofa HUANG
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1089-1093
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    Molecularly imprinted polymers (MIPs) were applied as molecular recognition elements to an electrochemical sensor for phenylephrine. A MIPs membrane was created on a glassy carbon electrode. SEM revealed a gradual change on the morphology of modified electrodes as the ratios of function monomer and cross-linking varied. When the ratio was 4:40, the surface morphology between the imprinted electrode (M-electrode) and the control electrode (N-electrode) became unambiguously different. This artificial receptor exhibited high selectivity for the template compared to closely related analogue. The response of the sensor varied in different concentration range might due to the heterogeneity of the MIPs membrane. This sensor was also used to determine phenylephrine in tablet samples.
  • Naoto SHIRASU, Takeshi ONODERA, Kazutaka NAGATOMO, Yasuyuki SHIMOHIGAS ...
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1095-1100
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    Benzaldehyde (Bz) is a typical fragrant compound for peach-flavored beverages. In the food and beverage industries there is great demand for a sensitive and easy detection system of Bz in order to ensure product quality control and to avoid contamination. For the noncompetitive detection of Bz, we applied an open-sandwich enzyme-linked immunosorbent assay (OS-ELISA) utilizing an antigen-dependent reassociation of antibody variable region fragments, VH and VL. We cloned the VH and VL genes of an anti-Bz monoclonal antibody, and the fragments were individually expressed and purified as a bacterial alkaline phosphatase (BAP)-conjugated form for VH and as a thioredoxine (Trx)-fused form for VL, respectively. Using these VH and VL fragments, we successfully constructed the OS-ELISA system for Bz detection. The Bz-induced formation of a trimolecular complex composed of VH-BAP/Bz/Trx-VL was readily detected by a dose-dependent increase in the BAP activity of the VH-fusion protein.
  • Hiroshi IWANAGA, Hirohiko TSUZUKI, Yoichiro KAMIYAMA, Hiroshi UEDA
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1101-1106
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    With a specific and strong molecular-recognition capability cultivated in humoral acquired immunity, an antibody has been extensively utilized in various applications, such as diagnostics and therapy. However, so far most of its uses have been limited to be in the liquid phase. In view of its potential uses, such as a gas-phase biosensor or a high-performance air filter, we have tried to verify a previously undescribed binding reaction between protein antigens and corresponding antibodies immobilized on a solid surface by using fluorescence resonance energy transfer between the two. Our data showed that the antibody on a solid surface specifically reacted with a protein antigen supplied from the gas phase under the normal ambient condition. Also discovered was that the reaction occurred even faster than that in the liquid phase under several assay conditions.
  • Tomohiko HIRANO, Shinya KITAGAWA, Hajime OHTANI
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1107-1113
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    Butyl methacrylate-based reversed phase capillary monolithic columns were prepared using ultraviolet (UV) photo-polymerization. The effects of two photo-polymerization conditions (UV irradiation intensity and polymerization temperature) on the column characteristics were investigated. Both the higher UV irradiation intensity and the lower polymerization temperature lead to the superior column efficiency. The column prepared under the optimized conditions was evaluated through the separation of the uracil and five alkylbenzenes in the linear flow rate range of 1 − 110 mm/s. At 1 mm/s, all analytes were well separated (N = 36000 − 45000 plates/m). The high speed separation within 8 s was performed at 110 mm/s (back pressure, 33 MPa) at room temperature, whereas the peaks eluted earlier were overlapped partially. The relationship between the flow rate and the back pressure indicated that some kind of structural change of the monolith might occur in 50 − 110 mm/s, although no visible or hysteresis changes of the monolith were observed after the measurement.
  • Pinjia MENG, Dan ZHU, Hongyuan HE, Yanyan WANG, Fei GUO, Liang ZHANG
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1115-1118
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    We report here on the results of a procedure for the determination of amphetamine drugs in hair. The procedure is simple and sensitive. The results from the procedure using small-volume extraction matches perfectly with those either from using the derivatization method or selected ion monitoring (SIM) detection. We validated our method using four different amine drugs, including amphetamine, methamphetamine, methylenedioxy-amphetamine and methylenedioxy-methamphetamine. The detection limit for these drugs is about 50 ± 7.5 pg/mg in hair and the intra-day and inter-day reproducibility are within 15% at most drug concentrations. Moreover, we also showed the utility of the procedure in analyses of authentic hair samples taken from amphetamine abusers, and demonstrated that the method meets the requirement for the analysis of a trace amounts of amphetamines in human hair.
  • Jing TIAN, Weidong QIN
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1119-1123
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    A capillary electrophoresis (CE)-potential gradient detection (PGD) method was developed for quick and sensitive determinations of puerarin, farrerol and baicalin. The flavonoids were baseline separated in 1.9 min with a buffer comprised of 20 mM tris(hydroxymethyl)aminomethane (Tris) and 3 mM HCl at pH 8.69. The analysis time is, to the best of our knowledge, the shortest for the CE analysis of flavonoids. The association constants, determined by affinity CE, suggested an ion-dipole or ion-induced dipole interaction between Tris and flavonoid molecules. The detection limits, in the range of 0.068 and 0.116 mg L−1, were lower than the early reported UV and chemiluminescence detection techniques. A solvent-extraction method was coupled to CE to determine baicalin in a Chinese herbal preparation Scutellaria Baicalensis Georgi. The concentration of baicalin in the sample was determined to be 5.1%. Validation of the method suggested its applicability in real sample analysis.
  • Yan LV, Tao YUAN, Jiangyong HU, Wenhua WANG
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1125-1130
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    電子付録
    This study intended to develop a robust and sensitive method for simultaneous determination of polycyclic musks (HHCB and AHTN) and nitro musks (musk xylene (MX) and musk ketone (MK)) in water samples using optimized solid-phase extraction (SPE) by gas chromatography and mass spectrometry (GC-MS). The SPE procedure was optimized in terms of selections of SPE cartridge, sample pH, elution process, etc. The method detection limits (MDLs) were from 0.09 to 0.18 ng L−1 for the analytes. The recoveries ranged from 88.3 to 104.1% in spiked deionized water and from 86.4 to 106.8% in groundwater samples, respectively. The proposed approach was also validated by detecting real samples. The results revealed that HHCB and AHTN were ubiquitous in the local aquatic matrices. Furthermore, nitro musks were found in some aquatic matrices, which is consistent with the fact that nitro musks are still being produced and applied in China.
  • Mohsen M. ZAREH
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1131-1135
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    A pH electrode for the selective determination of H+ was introduced. Both phosphorated calix[6]arene and a N,N′-bisethoxycarbonyl-1,10-diaza-4,7,13,16-tetraoxacyclo-octadecane (DZCE) were used as new H+-ionophores. The calibration graphs of the obtained electrodes exhibits satisfactory Nernstian slopes. The electrodes were compared to blank membranes (without any ionophoric substances) for the first time. Selectivity coefficients of the studied electrodes towards several inorganic cations were calculated. The relative selectivity coefficient (RSC) was applied for evaluating the selectivity properties of H+-electrode using a mathematical equation. The electrodes were applied for the determination of different inorganic and organic acids.
  • Hassan GOLMOHAMMADI, Elahe KONOZ, Zahra DASHTBOZORGI
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1137-1142
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    The main aim of the present work was development of a quantitative structure-property relationship method using an artificial neural network (ANN) for predicting gas-to-olive oil partition coefficients of organic compounds. As a first step, a multiple linear regression (MLR) model was developed; the descriptors appearing in this model were considered as inputs for the ANN. These descriptors are: solvation connectivity index χ−1, hydrophilic factor, conventional bond-order ID number, dipole moment and a total size index/weighted by atomic masses. Then a 5-5-1 neural network was generated for the prediction of gas-to-olive oil partition coefficients of 179 organic compounds including hydrocarbons, alkyl halides, alcohols, ethers, esters, ketones and benzene derivatives. The values of standard error for training, test and validation sets are 0.127, 0.122 and 0.162, respectively for ANN model. Comparisons between these values and other obtained statistical values reveal the superiority of the ANN model over the MLR one.
  • Hai-Yan FU, Shuang-Yan HUAN, Lu XU, Jian-Hui JIANG, Hai-Long WU, Guo-L ...
    原稿種別: Original Papers
    2009 年 25 巻 9 号 p. 1143-1148
    発行日: 2009/09/10
    公開日: 2009/09/10
    ジャーナル フリー
    This paper reports on the construction of an efficacious model for a non-invasive identification of traditional Chinese medicines, Liuwei Dihuang pills from different manufacturers, on the basis of near-infrared spectra (NIRS) coupled with moving window partial least-squares discriminant analysis (MWPLSDA). Considering the continuity of near-infrared spectral measurements, MWPLSDA is used to identify continuous and highly classification-related information intervals, a simple, yet effective classification model that can be developed for identifying accurate 150 Liuwei Dihuang pills from five different manufacturers. Meanwhile, the method is compared with some traditional pattern-recognition methods including principal component analysis (PCA), linear discriminant analysis (LDA) and partial least-squares discriminant analysis (PLSDA). The obtained results show that the method not only can reduce the operation time, but also significantly improves the classification accuracy. Hence, the nondestructive method can be expected to be promising for more practical applications on quality control and the discrimination of traditional Chinese medicine.
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