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1.
Application of surface chemical analysis tools for characterization of nanoparticles 总被引:1,自引:1,他引:0
D. R. Baer D. J. Gaspar P. Nachimuthu S. D. Techane D. G. Castner 《Analytical and bioanalytical chemistry》2010,396(3):983-1002
The important role that surface chemical analysis methods can and should play in the characterization of nanoparticles is
described. The types of information that can be obtained from analysis of nanoparticles using Auger electron spectroscopy
(AES), X-ray photoelectron spectroscopy (XPS), time-of-flight secondary-ion mass spectrometry (TOF-SIMS), low-energy ion scattering
(LEIS), and scanning-probe microscopy (SPM), including scanning tunneling microscopy (STM) and atomic force microscopy (AFM),
are briefly summarized. Examples describing the characterization of engineered nanoparticles are provided. Specific analysis
considerations and issues associated with using surface-analysis methods for the characterization of nanoparticles are discussed
and summarized, with the impact that shape instability, environmentally induced changes, deliberate and accidental coating,
etc., have on nanoparticle properties.
相似文献
2.
Nora Graf Thomas Gross Thomas Wirth Wilfried Weigel Wolfgang E. S. Unger 《Analytical and bioanalytical chemistry》2009,393(8):1907-1912
The chemical composition of the functional surfaces of substrates used for microarrays is one of the important parameters
that determine the quality of a microarray experiment. In addition to the commonly used contact angle measurements to determine
the wettability of functionalized supports, X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry
(ToF-SIMS) are more specific methods to elucidate details about the chemical surface constitution. XPS yields information
about the atomic composition of the surface, whereas from ToF-SIMS, information on the molecular species on the surface can
be concluded. Applied on printed DNA microarrays, both techniques provide impressive chemical images down to the micrometer
scale and can be utilized for label-free spot detection and characterization. Detailed information about the chemical constitution
of single spots of microarrays can be obtained by high-resolution XPS imaging.
Figure Eye-catching image for the graphical online abstract 相似文献
3.
Zhao Yue Waqas Khalid Marco Zanella Azhar Zahoor Abbasi Andrea Pfreundt Pilar Rivera Gil Kirsten Schubert Fred Lisdat Wolfgang J. Parak 《Analytical and bioanalytical chemistry》2010,396(3):1095-1103
Gold electrodes with switchable conductance are created by coating the gold surface with different colloidal quantum dots.
For the quantum dot immobilization, a dithiol compound was used. By polarizing the electrode and applying a light pointer,
local photocurrents were generated. The performance of this setup was characterized for a variety of different nanoparticle
materials regarding drift and signal-to-noise ratio. We varied the following parameters: quantum dot materials and immobilization
protocol. The results indicate that the performance of the sensor strongly depends on how the quantum dots are bound to the
gold electrode. The best results were obtained by inclusion of an additional polyelectrolyte film, which had been fabricated
using layer-by-layer assembly.
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4.
Semiconductor quantum dots and metal nanoparticles: syntheses,optical properties,and biological applications 总被引:1,自引:0,他引:1
Biju V Itoh T Anas A Sujith A Ishikawa M 《Analytical and bioanalytical chemistry》2008,391(7):2469-2495
We review the syntheses, optical properties, and biological applications of cadmium selenide (CdSe) and cadmium selenide–zinc
sulfide (CdSe–ZnS) quantum dots (QDs) and gold (Au) and silver (Ag) nanoparticles (NPs). Specifically, we selected the syntheses
of QDs and Au and Ag NPs in aqueous and organic phases, size- and shape-dependent photoluminescence (PL) of QDs and plasmon
of metal NPs, and their bioimaging applications. The PL properties of QDs are discussed with reference to their band gap structure
and various electronic transitions, relations of PL and photoactivated PL with surface defects, and blinking of single QDs.
Optical properties of Ag and Au NPs are discussed with reference to their size- and shape-dependent surface plasmon bands,
electron dynamics and relaxation, and surface-enhanced Raman scattering (SERS). The bioimaging applications are discussed
with reference to in vitro and in vivo imaging of live cells, and in vivo imaging of cancers, tumor vasculature, and lymph
nodes. Other aspects of the review are in vivo deep tissue imaging, multiphoton excitation, NIR fluorescence and SERS imaging,
and toxic effects of NPs and their clearance from the body.
Figure Semiconductor quantum dots and metal nanoparticles have extensive applications, e.g., in vitro and in vivo bioimaging
Tamitake Itoh and Abdulaziz Anas contributed equally to this article. 相似文献
5.
Sen Hou Xinxin Li Xiaoyu Li Xi-Zeng Feng Rui Wang Chen Wang Lei Yu Ming-Qiang Qiao 《Analytical and bioanalytical chemistry》2009,394(3):783-789
Surface wettability conversion with hydrophobins is important for its applications in biodevices. In this work, the application
of a type I hydrophobin HGFI in surface wettability conversion on mica, glass, and poly(dimethylsiloxane) (PDMS) was investigated.
X-ray photoelectron spectroscopy (XPS) and water-contact-angle (WCA) measurements indicated that HGFI modification could efficiently
change the surface wettability. Data also showed that self-assembled HGFI had better stability than type II hydrophobin HFBI.
Protein patterning and the following immunoassay illustrated that surface modification with HGFI should be a feasible strategy
for biosensor device fabrication.
Figure A hydrophobin HGFI has been applied into surface wettability conversion for protein immobilization
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
Rudolf Tuckermann Ljiljana Puskar Mahta Zavabeti Ryo Sekine Don McNaughton 《Analytical and bioanalytical chemistry》2009,394(5):1433-1441
An experimental apparatus combining Raman spectroscopy with acoustic levitation, Raman acoustic levitation spectroscopy (RALS),
is investigated in the field of physical and chemical analytics. Whereas acoustic levitation enables the contactless handling
of microsized samples, Raman spectroscopy offers the advantage of a noninvasive method without complex sample preparation.
After carrying out some systematic tests to probe the sensitivity of the technique to drop size, shape, and position, RALS
has been successfully applied in monitoring sample dilution and preconcentration, evaporation, crystallization, an acid–base
reaction, and analytes in a surface-enhanced Raman spectroscopy colloidal suspension.
Figure We have systematically investigated the analytical potential of Raman spectroscopy of samples in acoustically levitated drops. 相似文献
7.
Berchmans S Vergheese TM Kavitha AL Veerakumar M Yegnaraman V 《Analytical and bioanalytical chemistry》2008,390(3):939-946
The present work describes, for the first time, in situ electrochemical preparation of dendrimer-encapsulated Cu nanoparticles
using a self-assembled monolayer of fourth-generation amine-terminated polyamidoamine (PAMAM) dendrimer as the template. Atomic
force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) studies of the modified surface confirmed the presence of
Cu nanoparticles entrapped in dendrimer film. Au electrode modified with a monolayer of the dendrimer enables preconcentration
and subsequent voltammetric detection of Cu2+ at picomolar concentrations. Further, Cu nanoparticles in the dendrimer monolayer could be electrochemically derivatised
to Cu hexacyanoferrate, which exhibits specific crystal planes, unlike the random distribution of crystal planes in bulk-formed
Cu hexacyanoferrate, which is another catalytically active material for sensor applications.
Figure Electrochemical preparation of copper–dendrimer nanocomposite 相似文献
8.
Two-dimensional liquid chromatography of synthetic polymers 总被引:2,自引:0,他引:2
Dušan Berek 《Analytical and bioanalytical chemistry》2010,396(1):421-441
Two-dimensional liquid chromatography, 2D-LC of synthetic polymers is critically assessed. Similarities and differences of
2D-LC of low-molecular-mass and polymeric substances are reviewed. The rationale of application of 2D-LC to macromolecular
substances is discussed. Basic information on retention mechanisms in liquid chromatography of synthetic polymers is furnished.
The principles, reasons, and significance of coupling of retention mechanisms are explained. The resulting separation processes
are elucidated, and the technical concepts of the corresponding experimental arrangements are described. The benefits of 2D-LC
are demonstrated together with numerous problems and shortcomings of the method.
相似文献
9.
Sara Wallin Anna Pettersson Henric Östmark Alison Hobro 《Analytical and bioanalytical chemistry》2009,395(2):259-274
A review of standoff detection technologies for explosives has been made. The review is focused on trace detection methods
(methods aiming to detect traces from handling explosives or the vapours surrounding an explosive charge due to the vapour
pressure of the explosive) rather than bulk detection methods (methods aiming to detect the bulk explosive charge). The requirements
for standoff detection technologies are discussed. The technologies discussed are mostly laser-based trace detection technologies,
such as laser-induced-breakdown spectroscopy, Raman spectroscopy, laser-induced-fluorescence spectroscopy and IR spectroscopy
but the bulk detection technologies millimetre wave imaging and terahertz spectroscopy are also discussed as a complement
to the laser-based methods. The review includes novel techniques, not yet tested in realistic environments, more mature technologies
which have been tested outdoors in realistic environments as well as the most mature millimetre wave imaging technique.
Figure Standoff detection and identification is one of the most wanted capabilities 相似文献
10.
Kevin A. Wepasnick Billy A. Smith Julie L. Bitter D. Howard Fairbrother 《Analytical and bioanalytical chemistry》2010,396(3):1003-1014
To utilize carbon nanotubes (CNTs) in various commercial and scientific applications, the graphene sheets that comprise CNT
surfaces are often modified to tailor properties, such as dispersion. In this article, we provide a critical review of the
techniques used to explore the chemical and structural characteristics of CNTs modified by covalent surface modification strategies
that involve the direct incorporation of specific elements and inorganic or organic functional groups into the graphene sidewalls.
Using examples from the literature, we discuss not only the popular techniques such as TEM, XPS, IR, and Raman spectroscopy
but also more specialized techniques such as chemical derivatization, Boehm titrations, EELS, NEXAFS, TPD, and TGA. The chemical
or structural information provided by each technique discussed, as well as their strengths and limitations. Particular emphasis
is placed on XPS and the application of chemical derivatization in conjunction with XPS to quantify functional groups on CNT
surfaces in situations where spectral deconvolution of XPS lineshapes is ambiguous.
相似文献
11.
Bo Yan Zheng-Jiang Zhu Oscar R. Miranda Apiwat Chompoosor Vincent M. Rotello Richard W. Vachet 《Analytical and bioanalytical chemistry》2010,396(3):1025-1035
Monolayer-protected gold nanoparticles (AuNPs) feature unique surface properties that enable numerous applications. Thus,
there is a need for simple, rapid, and accurate methods to confirm the surface structures of these materials. Here, we describe
how laser desorption/ionization mass spectrometry (LDI-MS) can be used to characterize AuNPs with neutral, positively, and
negatively charged surface functional groups. LDI readily desorbs and ionizes the gold-bound ligands to produce both free
thiols and disulfide ions in pure and complex samples. We also find that LDI-MS can provide a semi-quantitative measure of
the ligand composition of mixed-monolayer AuNPs by monitoring mixed disulfide ions that are formed. Overall, the LDI-MS approach
requires very little sample, provides an accurate measure of the surface ligands, and can be used to monitor AuNPs in complex
mixtures.
相似文献
12.
Christopher T. Kingston Yadienka Martínez-Rubí Jingwen Guan Michael Barnes Christine Scriver Ralph E. Sturgeon Benoit Simard 《Analytical and bioanalytical chemistry》2010,396(3):1037-1044
We have successfully applied coupled thermogravimetry, mass spectrometry, and infrared spectroscopy to the quantification
of surface functional groups on single-walled carbon nanotubes. A high-purity single-walled carbon nanotube sample was subjected
to a rapid functionalization reaction that attached butyric acid moieties to the nanotube sidewalls. This sample was then
subjected to thermal analysis under inert desorption conditions. Resultant infrared and mass spectrometric data were easily
utilized to identify the desorption of the butyric acid groups across a narrow temperature range and we were able to calculate
the degree of substitution of the attached acid groups within the nanotube backbone as 1.7 carbon atoms per hundred, in very
good agreement with independent analytical measurements made by inductively coupled plasma optical emission spectrometry (ICP-OES).
The thermal analysis technique was also able to discern the presence of secondary functional moieties on the nanotube samples
that were not accessible by ICP-OES. This work demonstrates the potential of this technique for assessing the presence of
multiple and diverse functional addends on the nanotube sidewalls, beyond just the principal groups targeted by the specific
functionalization reaction.
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13.
14.
This paper reports on an integrated analytical approach for the noninvasive characterization of Chinese nephrite samples,
encompassing both geological reference specimens and museum objects. Natural variations induced by cationic substitutions,
as well as human-induced alterations such as heating, which both affect color, are the focus of this contribution. Totally
noninvasive methods of analysis were used, including X-ray fluorescence spectroscopy, Raman microspectroscopy, visible reflectance
spectroscopy and X-ray diffraction; moreover, the feasibility of using a portable Raman spectrometer for the in-field identification
of jades has been demonstrated. Fe/Fe+Mg (% p.f.u.) ratios of the jades have been calculated based on hydroxyl stretching
Raman bands, which will provide an important addition to similar data that are being collected at major museums in the Western
and Eastern hemispheres.
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15.
16.
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
17.
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
18.
Benko B Kalász H Ludányi K Petroianu G Kuca K Darvas F Tekes K 《Analytical and bioanalytical chemistry》2007,389(4):1243-1247
Metabolic pathways of the oxime K-48 have been elucidated by means of in vitro and in vivo experiments. K-48 exposure to rat
liver microsomal fraction resulted in the formation of a hydroxylated derivative, in addition to a small molecular fragment.
The in vivo metabolism in rats was investigated after intramuscular administration of 50 μmol oxime. K-48 was present in the
rat serum in unchanged form. Similarly, the analysis of rat cerebrospinal fluid indicated the sole occurrence of unchanged
K-48. In contrast, unchanged K-48 was not found in the rat urine, where only the metabolite generated by epoxidation on the
alkyl chain connecting the two pyridinium rings was present. The presence of unchanged K-48 in the serum and cerebrospinal
fluid facilitates quantitative determination using HPLC separation and ultraviolet absorbance detection.
Figure Suggested metabolic pathways of K-48 相似文献
19.
Emily O’Neill Danielle Harrington John Allison 《Analytical and bioanalytical chemistry》2009,393(8):2029-2038
Monitoring of cell cultures in microbioreactors is a crucial task in cell bioassays and toxicological tests. In this work
a novel tool based on a miniaturized sensor array fabricated using low-temperature cofired ceramics (LTCC) technology is presented.
The developed device is applied to the monitoring of cell-culture media change, detection of the growth of various species,
and in toxicological studies performed with the use of cells. Noninvasive monitoring performed with the LTCC microelectrode
array can be applied for future cell-engineering purposes.
Figure Microelectrode array for monitoring of cell cultures 相似文献
20.
Sen Hou Xin-Xin Li Xiao-Yu Li Xi-Zeng Feng Li Guan Yan-Lian Yang Chen Wang 《Analytical and bioanalytical chemistry》2009,394(8):2111-2117
Controllable cell growth on the defined areas of surfaces is important for potential applications in biosensor fabrication
and tissue engineering. In this study, controllable cell growth was achieved by culturing 293 T fibroblast cells on a mica
surface which had been patterned with collagen strips by a microcontact printing (μCP) technique. The collagen area was designed
to support cell adhesion and the native mica surface was designed to repel cell adhesion. Consequently, the resulting cell
patterns should follow the micro-patterns of the collagen. X-ray photoelectron spectroscopy (XPS), water contact angle (WCA)
measurement, atomic-force microscope (AFM) observation, and force-curve measurement were used to monitor property changes
before and after the collagen adsorption process. Further data showed that the patterned cells were of good viability and
able to perform a gene-transfection experiment in vitro. This technique should be of potential applications in the fields
of biosensor fabrication and tissue engineering.
Figure Controllable cells growth has been achieved by culturing 293T fibroblast cells on the mica surface which had been patterned
with collagen strips by microcontact printing (μCP) technique 相似文献