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Lee JO So HM Jeon EK Chang H Won K Kim YH 《Analytical and bioanalytical chemistry》2008,390(4):1023-1032
Recent advances in nanotechnology have enabled the development of nanoscale sensors that outperform conventional biosensors.
This review summarizes the nanoscale biosensors that use aptamers as molecular recognition elements. The advantages of aptamers
over antibodies as sensors are highlighted. These advantages are especially apparent with electrical sensors such as electrochemical
sensors or those using field-effect transistors.
Figure Feeling proteins with aptamer-functionalized carbon nanotubes 相似文献
3.
Sensor technology and its application in environmental analysis 总被引:1,自引:0,他引:1
Environmental analysis is one of the fundamental applications of chemical sensors. In this review we describe different sensor
systems for the gas and liquid phases that have been tested either with real-life samples or in the field during the last
five years. Most field sensors rely either on electrochemical or optical transducers. In the gas phase, systems have been
proposed for analysis of oxides of nitrogen, carbon, and sulfur in air, and volatile organic compounds. In the liquid phase,
most detection systems used for real-life samples detect heavy-metal ions or organic contamination, for example pesticides,
organic solvents and polycyclic aromatic hydrocarbons.
Figure Chemical sensors for real-life environmental applications
Dedicated to Professor Ulrich Nickel on the occasion of his 65th birthday. 相似文献
4.
Cordes DB Miller A Gamsey S Singaram B 《Analytical and bioanalytical chemistry》2007,387(8):2767-2773
The simultaneous use of several fluorescent reporter dyes in a multicomponent boronic acid-based glucose sensing system is
reported. In one application, two dyes with widely different emission wavelengths are used to report changes in glucose concentration.
A third glucose-insensitive dye was then added to act as a reference dye and provide for a ratiometric correction to the two
reporter dye signals. The inclusion of such a reference dye reduces errors arising from sources such as fluctuations in lamp
intensity and sample dilution.
The simultaneous use of multiple fluorescent reporter dyes 相似文献
5.
Eric B. Kalman Olivier Sudre Ivan Vlassiouk Zuzanna S. Siwy 《Analytical and bioanalytical chemistry》2009,394(2):413-419
Control of ionic transport through nanoporous systems is a topic of scientific interest for the ability to create new devices
that are applicable for ions and molecules in water solutions. We show the preparation of an ionic transistor based on single
conical nanopores in polymer films with an insulated gold thin film “gate.” By changing the electric potential applied to
the “gate,” the current through the device can be changed from the rectifying behavior of a typical conical nanopore to the
almost linear behavior seen in cylindrical nanopores. The mechanism for this change in transport behavior is thought to be
the enhancement of concentration polarization induced by the gate.
Figure
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
SPME in environmental analysis 总被引:1,自引:0,他引:1
Recent advances in the use of solid-phase microextraction (SPME) in environmental analysis, including fiber coatings, derivatization
techniques, and in-tube SPME, are reviewed in this article. Several calibration methods for SPME, including traditional calibration
methods, the equilibrium extraction method, the exhaustive extraction method, and several diffusion-based calibration methods,
are presented. Recent developed SPME devices for on-site sampling and several applications of SPME in environmental analysis
are also introduced.
相似文献
7.
Willard DM Mutschler T Yu M Jung J Van Orden A 《Analytical and bioanalytical chemistry》2006,384(3):564-571
Nanoscale sensors can be created when an expected energetic pathway is created and then that pathway is either initiated or
disrupted by a specific binding event. Constructing the sensor on the nanoscale could lead to greater sensitivity and lower
limits of detection. To this end, quantum dots (QDs) can be considered prime candidates for the active components. Relative
to organic chromophores, QDs have tunable spectral properties, show less susceptibility to photobleaching, have similar brightness,
and have been shown to display electro-optical properties. In this review, we discuss recent articles that incorporate QDs
into directed energy flow systems, some with the goal of building new and more powerful sensors and others that could lead
to more powerful sensors.
Figure 相似文献
8.
Pérez-Quintanilla D del Hierro I Carrillo-Hermosilla F Fajardo M Sierra I 《Analytical and bioanalytical chemistry》2006,384(3):827-838
Amorphous silicas have been functionalized by two different methods. In the heterogeneous route the silylating agent, 3-chloropropyltriethoxysilane,
was initially immobilized onto the silica surface to give the chlorinated silica Cl-Sil. In a second reaction, multifunctionalized
N,S donor compounds were incorporated to obtain the functionalized silicas, which are denoted as L-Sil-Het (where L=mercaptothiazoline,
mercaptopyridine or mercaptobenzothiazole). In the homogeneous route, the functionalization was achieved through a one-step
reaction between the silica and an organic ligand containing the chelating functions; this gave the modified silicas denoted
as L-Sil-Hom. The functionalized silicas were characterized by elemental analysis, IR spectroscopy and thermogravimetry. These
materials were employed as adsorbents for mercury cations from aqueous and acetone solutions at room temperature. The results
indicate that, in all cases, mercury adsorption was higher in the modified silicas prepared by the homogeneous method.
Figure 相似文献
9.
Alvarado Tarun Norihiko Hayazawa Satoshi Kawata 《Analytical and bioanalytical chemistry》2009,394(7):1775-1785
Tip-enhanced Raman spectroscopy (TERS), which utilizes the strong localized optical field generated at the apex of a metallic
tip when illuminated, has been shown to successfully probe the vibrational spectrum of today’s and tomorrow’s state-of-the-art
silicon and next-generation semiconductor devices, such as quantum dots. Collecting and analyzing the vibrational spectrum
not only aids in material identification but also provides insight into strain distributions in semiconductors. Here, the
potential of TERS for nanoscale characterization of strain in silicon devices is reviewed. Emphasis will be placed on the
key challenges of obtaining spectroscopic images of strain in actual strained silicon devices.
Figure Figure Concept of Tip Enhanced Raman Spectroscopy (TERS), which utilizes the strong localized optical field generated at the
apex of a metallic tip when illuminated. TERS has been demonstrated to successfully probe the vibrational spectrum of today’s
and tomorrow’s state-of-the-art silicon and next generation semiconductor devices 相似文献
10.
Pérez Pavón JL García Pinto C Guerrero Peña A Moreno Cordero B 《Analytical and bioanalytical chemistry》2008,391(2):599-607
In the present work we report the results obtained with a methodology based on direct coupling of a headspace generator to
a mass spectrometer for the identification of different types of petroleum crudes in polluted soils. With no prior treatment,
the samples are subjected to the headspace generation process and the volatiles generated are introduced directly into the
mass spectrometer, thereby obtaining a fingerprint of volatiles in the sample analysed. The mass spectrum corresponding to
the mass/charge ratios (m/z) contains the information related to the composition of the headspace and is used as the analytical signal for the characterization
of the samples. The signals obtained for the different samples were treated by chemometric techniques to obtain the desired
information. The main advantage of the proposed methodology is that no prior chromatographic separation and no sample manipulation
are required. The method is rapid, simple and, in view of the results, highly promising for the implementation of a new approach
for oil spill identification in soils.
Figure PCA score plots illustrate clear discrimination of types of crude oil in polluted soil samples (e.g. results are shown for
vertisol) 相似文献
11.
12.
Rosenberg E 《Analytical and bioanalytical chemistry》2008,391(1):33-57
This review discusses the characterisation of natural organic dyestuffs of historical interest by liquid chromatography–mass
spectrometry. The structures of the most important natural organic dyestuffs traditionally used are presented and discussed
from the perspective of their analytical chemical determination. The practical aspects of the determination of this inhomogeneous
range of compounds with different structures, such as anthraquinones, flavonoids, indigoids or tannins, are discussed with
their implications for sample preparation, liquid chromatographic separation and mass spectrometric detection. The particular
focus of this review is the discussion of the mass spectral fragmentation patterns of the different classes of natural organic
dyestuffs, which in the ideal case allow the identification of the dyestuff actually used, and thereby provide a key to the
better characterisation and understanding of historical objects dyed with natural organic dyestuffs.
Figure LC-MS allows characterisation of natural dyestuff constituents: the MS spectrum of alizarin is superimposed over a photo of
a textile coloured using this red dye 相似文献
13.
Webb A 《Analytical and bioanalytical chemistry》2007,388(3):525-528
Figure Schematic diagram of a typical arrangement used for hyphenating chemical microseparations (e.g. capillary HPLC, CE, or CEC)
with microcoil NMR detection 相似文献
14.
We report a simple method that combines dialysis, as a purification method, with the multielement capability of ICP to determine
the titanium-to-transferrin mole ratio at physiological pH, under buffer conditions. The method, by means of which titanium
and transferrin are determined simultaneously, enabled us to assess the binding capacities of different titanocene complexes.
Figure Titanocene dichloride 相似文献
15.
The use of polymers in microchip fabrication affords new opportunities for the development of powerful, miniaturized separation
techniques. One method in particular, the use of phase-changing sacrificial layers, allows for simplified designs and many
additional features to the now standard fabrication of microchips. With the possibility of adding a third dimension to the
design of separation devices, various means of enhancing analysis now become possible. The application of phase-changing sacrificial
layers in microchip analysis systems is discussed, both in terms of current uses and future possibilities.
Figure Phase-changing sacrificial materials enable multilayer microfluidic device layouts 相似文献
16.
Alain Walcarius 《Analytical and bioanalytical chemistry》2010,396(1):261-272
Nano- and/or macrostructuring of electrode surfaces has recently emerged as a powerful method of improving the performances
of electrochemical devices by enhancing both molecular accessibility and rapid mass transport via diffusion, by increasing
the electroactive surface area in comparison to the geometric one, and/or by providing confinement platforms for hosting suitable
reagents. This brief overview highlights how template technology offers advantages in terms of designing new types of porous
electrodes—mostly based on thin films, and functionalized or not—and discusses their use in analytical chemistry via some
recent examples from the literature on electrochemical sensors and biosensors.
相似文献
17.
Microfluidics offers an ideal platform to integrate cell-based assays with electric measurements. The technological advances
in microfluidics, microelectronics, electrochemistry, and electrophysiology have greatly inspired the development of microfluidic/electric
devices that work with a low number of cells or single cells. The applications of these microfluidic systems range from the
detecting of cell culture density to the probing of cellular functions at the single-cell level. In this review, we introduce
the recent advances in the electric analysis of cells on a microfluidic platform, specifically related to the quantification
and monitoring of cells in static solution, on-chip patch-clamp measurement, and examination of flowing cells. We also point
out future directions and challenges in this field.
Figure Different microfluidic devices applied to electrical analysis of cells 相似文献
18.
Ma X Zhu T Xu H Li G Zheng J Liu A Zhang J Du H 《Analytical and bioanalytical chemistry》2008,390(4):1133-1137
A chemical prototype sensor was constructed based on nanofiber-structured TiO2 and highly sensitive quartz resonators. The gas-sensing behavior of this new sensor to selected simulant warfare agents was
investigated at room temperature. Results showed rapid response and good reversibility of this sensor when used with high-purity
nitrogen. This provides a simple approach to preparation of materials needed as chemical sensors for selected organic volatiles
or warfare agents.
Figure Sensing behavior of TiO2 nanofiber sensor to chemical vapors 相似文献
19.
This work is devoted to the EXAFS analysis of nanostructured iron(III) oxide synthesized inside the pore system of mesoporous
carbon CMK-1. A detailed study of the recording, preparation and evaluation of data recorded in fluorescence mode at the iron
K-edge with and without multiple scattering is shown. The results obtained show that the local structure of Fe3+ inside nanostructured iron(III) oxide is different to that of the bulk material. Due to the small particle size, data analysis
is much more difficult and data preparation more complex. Incorporating multiple scattering paths in the Fourier transforms
and back-transforms during data evaluation gives structural insights that cannot be obtained using other spectroscopic methods,
and this technique was used to draw conclusions about the first four coordination spheres of the nanostructured iron(III)
oxide.
相似文献
20.
A. Hartschuh H. Qian C. Georgi M. Böhmler L. Novotny 《Analytical and bioanalytical chemistry》2009,394(7):1787-1795
We review recent experimental studies on single-walled carbon nanotubes on substrates using tip-enhanced near-field optical
microscopy (TENOM). High-resolution optical and topographic imaging with sub 15 nm spatial resolution is shown to provide
novel insights into the spectroscopic properties of these nanoscale materials. In the case of semiconducting nanotubes, the
simultaneous observation of Raman scattering and photoluminescence (PL) is possible, enabling a direct correlation between
vibrational and electronic properties on the nanoscale. So far, applications of TENOM have focused on the spectroscopy of
localized phonon modes, local band energy renormalizations induced by charge carrier doping, the environmental sensitivity
of nanotube PL, and inter-nanotube energy transfer. At the end of this review we discuss the remaining limitations and challenges
in this field.
Figure Tip-enhanced Raman scattering and photoluminescence spectroscopy with sub 15 nm spatial resolution provides novel insights
into the electronic and vibronic properties of single-walled carbon nanotubes. 相似文献