An International Quarterly Research Journal

ACL

                                                                                                      ISSN : 0971 - 9822

                                                                           Vol 16,  No 3,  April-June, 2012

Asian Chemistry Letters                                                                                                             Vol. 16, No. 3 (2012)00-00


QCM and SERS combination off-line to detect thrombin based on aptamer technology

 

Xiaolei Yue, Hui Hu, Xiaodong Zhou,*  and Jiming Hu*

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education),

College of Chemistry and Molecular Sciences, Wuhan University, China

Institute of Analytical Biomedicine, College of Chemistry and Molecular Sciences,

Wuhan University, Wuhan 430072, China

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We report for the first time the combination of Quartz Crystal Microbalance (QCM) and surface-enhancement Raman spectroscopy (SERS) for thrombin detection. 1,6-dithiolhexnol was assembled onto the gold electrode of crystal slide. Then, 20 nm GNPs were assembled on this layer with stable gold-sulfur linkage to form a two-dimensional nanoarray interface. Thiol-modified aptamers were assembled onto the interface for capturing thrombin. In the QCM detection process, in order to amplify the frequency signal, aptamer-functionalized gold nanoparticles were added. Meanwhile, the Raman reporter, 4-mercaptobenzoic acid was modified on the gold nanoparticles, so that, with this functionalized nanoparticles as the tag, QCM and SERS combination detection for thrombin was set up on the same interface.

Total Refs : 16

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Asian Chemistry Letters                                                                                                             Vol. 16, No. 3 (2012)00-00

 

LOC-SERS using metal nanoparticles for quantitative detection of the

simulated metabolism of nicotine in urine

 

Anne März, Dana Cialla, Karina Weber, Petra Rösch and  Jürgen Popp*

Institute of Physical Chemistry and Abbe-Center of Photonics,

Friedrich-Schiller University Jena,Helmholtzweg 4, 07743 Jena, Germany

Institute of Photonic Technologies (IPHT), Albert Einstein Straße 9, 07745 Jena, Germany

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In this contribution the great potential of surface enhanced Raman spectroscopy (SERS) in a lab-on-a-chip device (LOC) for the quantitative analysis of molecules in a complex environment is demonstrated. The quantification of nicotine in synthetic urine based on a simulated metabolism of nicotine to cotinine, one metabolite of the alkaloid, is carried out by applying a partial least square analysis (PLS) as statistic method. It can be shown that even in a complex environment a quantification of nicotine can be realized by the use of statistic methods. This is a promising approach towards the diagnosis of drugs in urine by the means of SERS

Total Refs : 47

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Asian Chemistry Letters                                                                                                             Vol. 16, No. 3 (2012)00-00

 

Green chemistry synthesis of gold nanoparticles at room temperature

using black and green tea

 

U S Mohanty1* and V N Misra2

1Department of Materials Science and Engineering, National Cheng Kung University, Taiwan

2Department of State Development, Adelaide Terrace, Perth, Western Australia 

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The synthesis of gold nanoparticles using green chemistry methods has been investigated. The phytochemicals present in black and green tea namely epigallocatechin gallate (EGCG) and tannic acid served as potential reductants in the synthesis process.  UV -visible spectra for gold nanoparticles obtained from black and green tea revealed the presence of surface plasmon reasonance (SPR) bands both in the visible and NIR region which underwent blue shift with increased concentration of tea leaves. The SPR bands in the visible and NIR region indicated the formation of both spherical and triangular nanoprisms which were clearly reflected in the TEM images. It is also demonstrated that the temperature of the gold nanoparticle (Au NP) solutions obtained from black and green tea was elevated when irradiated by NIR light radiation (808 nm) for few minutes. Also the GNP synthesized from black tea acted as better nanoscale absorbers of laser light than obtained from green tea. The intensity and sharpness of the SPR bands in the UV spectra increased with increase in concentration of epigallocatechin gallate (EGCG) and tannic acid in the bath containing HAuCl4.

Total Refs : 44

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Asian Chemistry Letters                                                                                                             Vol. 16, No. 3 (2012)00-00


Morpho-structural analysis of porous TiO2-WO3 aerogels


M Rusu1, A Radu1, I J Hidi1, A Vulpoi2, M Baia1,2, L Pop3, V Danciu3 and L Baia1,2*

1Faculty of Physics, Babeş-Bolyai University, 1 Kogălniceanu str., 400084 Cluj-Napoca, Romania

2Institute for Interdisciplinary Research on Bio-Nano-Science, Babes-Bolyai University,

Treboniu Laurian Street 42, 400271, Cluj-Napoca, Romania

3Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University 400028, Cluj-Napoca, Romania

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In the present study the morpho-structural properties of TiO2-WO3 composites obtained by sol-gel method were investigated. The XRD and Raman measurements revealed that upon thermal treatment at 600 oC an anatase-like structure was obtained.Furthermore, from the assessment of the crystallite’s mean size it was demonstrated that the tungsten oxide addition has an inhibitory effect on the growth of the TiO2 crystallites. Based on BET and UV-Vis measurements it was found that an optimal loading exists. The sample with 7% (wt. %) WO3 exhibits the highest surface area (139.1 m2/g) and a 30 nm red-shift of the absorption edge.

Total Refs : 36

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Asian Chemistry Letters                                                                                                             Vol. 16, No. 3 (2012)00-00


Atom-pairs correlations within Ag2O∙B2O3∙CaO∙P2O5 vitreous system


Razvan Stefan1, Emil Indrea2, Emil Vinteler3*

1University of Agricultural Sciences and Veterinary Medicine, 3-5 Manastur Street, Cluj-Napoca, Romania

2National Institute for R&D of Isotopic and Molecular Technology, 65-103 Donath Street, Cluj-Napoca, Romania

3Babeş-Bolyai University, 1 M. Kogalniceanu Street, Cluj-Napoca, Romania

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The vitreous system 1.5%Ag2O∙98.5%[0.47B2O3∙(0.53-x) CaO∙xP2O5] has been prepared by utilizing rapid melt cooling procedure.The atomic-scale structure of the vitreous system has been studied by means of X-ray diffraction and through atomic pair distribution function technique. The B-O, B-B, Ca-O, O-O correlations within the glass have been highlighted in relation to glass composition.

Total Refs : 19

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Asian Chemistry Letters                                                                                                             Vol. 16, No. 3 (2012)00-00

 

XRD and FTIR investigation of sol-gel derived lanthanum based nanostructures

 

S  Simon

Babeş-Bolyai University, Faculty of Physics & Interdisciplinary Research Institute on Bio-Nano-Sciences,

 400048 Cluj-Napoca, Romania 

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Structural properties of sol-gel derived lanthanum based samples heat treated at relative low temperatures, up to 650 oC, are reported. The type and size of the nanocrystallites developed in these samples depend on heat treatment temperature. The results point out structural changes from lanthanum hydroxycarbonate to hydroxynitrate and hydroxide with the increase of heat treatment temperature from 300 to 650oC.

Total Refs : 24

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Asian Chemistry Letters                                                                                                             Vol.16, No. 3, (2012)00-00


                           Nanoarchitectures based on Tio2 aerogels and noble metal particles

                                                 for chemical pollutants detection

 

V Iancua, L Baiaa,b, V Danciuc, M Baiaa,b*

aFaculty of Physics, Babes-Bolyai University, M. Kogalniceanu 1, 400084, Cluj-Napoca, Romania

bInstitute for Interdisciplinary Research in Bio-Nano-Sciences, Babes-Bolyai University,

 Treboniu Laurian Street 42, 400271, Cluj-Napoca, Romania

cFaculty of Chemistry and Chemical Engineering, Babes-Bolyai University,

 Arany Janos 11, 400028, Cluj-Napoca, Romania

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Since the TiO2 environmental friendly character and the affinity of a large variety of molecules to bind to the gold and silver nanostructures surfaces are well-known, we have obtained novel porous nanoarchitectures based on TiO2 aerogel and Au and Ag colloidal particles, respectively. Their ability to detect contaminant species adsorbed from aqueous media was tested. Being synthesized through various methods, the efficiency of the composites to detect pollutants from water via surface-enhanced Raman spectroscopy (SERS) was assessed by using thioacetamide, acrylamide, crystal violet and rhodamine 6G as test molecules. Depending on the sample preparation method and pollutant species type, the lowest detectable concentrations were found be of around 10-2 M for thioacetamide, 10-3 for acrylamide, and in-between 10-5 and 10-10 M for dye molecules off and under resonant excitation, respectively. The obtained results show the real potential of the prepared porous composites for further use in the development of new SERS-based sensors for monitoring of water quality.

Total Refs : 33

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Asian Chemistry Letters                                                                                                             Vol. 16, No. 3 (2012)00-00

 

Atomic environment changes induced by ThO2 addition to soda-phosphate glasses

 

V Simon

Babeş-Bolyai University, Faculty of Physics & Interdisciplinary Research Institute on Bio-Nano-Sciences,

400048 Cluj-Napoca, Romania

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Information about the atomic structure of phosphate glasses containing nuclear waste components is essential for a comprehensive scientific assessment of their use in nuclear waste disposal. The effect on local structure of a P2O5-Na2O glass induced by thorium incorporation/integration was evidenced by FTIR analysis. The changes in the electronic polarizability of the samples are also considered.

Total Refs : 20

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