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You searched for: Journal name Talanta Remove constraint Journal name: Talanta Publication year rev 7989-2011 Remove constraint Publication year rev: 7989-2011 Source 2011 v.83 no.5 Remove constraint Source: 2011 v.83 no.5
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1. A cation exchange resin bead-based microscale electrolytic suppressor for capillary ion chromatography

Author:
Feifang Zhang; Yapu Li; Bingcheng Yang; Xinmiao Liang
Source:
Talanta 2011 v.83 no.5 pp. 1496-1500
ISSN:
0039-9140
Subject:
cation exchange; electrical resistance; ion exchange chromatography; potassium hydroxide; sulfuric acid; surface area
Abstract:
... A cation exchange resin (CER) bead-based microscale electrolytic suppressor for capillary ion chromatography (CIC) has been fabricated and evaluated. Relative to common ion exchange membrane, the use of CER beads presents a simple way to fabricate a microscale suppressor due to its small surface area and spherical shape. The internal volume of the device is ∼600nL, which matches the requirements b ...
DOI:
10.1016/j.talanta.2010.11.043

2. A new potentiometric sensor for the determination of α-amylase activity

Author:
Nikola Sakač; Milan Sak-Bosnar; Marija Horvat; Dubravka Madunić-Čačić; Aleksandar Szechenyi; Barna Kovacs
Source:
Talanta 2011 v.83 no.5 pp. 1606-1612
ISSN:
0039-9140
Subject:
alpha-amylase; detection limit; models; platinum; potassium; proteinases; spectrophotometers; starch; Switzerland
Abstract:
... A platinum redox sensor for the direct potentiometric determination of α-amylase concentration has been described. The sensor measured the amount of triiodide released from a starch–triiodide complex, which was correlated with the α-amylase activity after biocatalytic starch degradation. The composition and stability of the potassium triiodide solution was optimized. The starch–triiodide complex w ...
DOI:
10.1016/j.talanta.2010.11.053

3. Bicontinuous gyroidal mesoporous carbon matrix for facilitating protein electrochemical and bioelectrocatalytic performances

Author:
Chunping You; Xuewu Yan; Jilie Kong; Dongyuan Zhao; Baohong Liu
Source:
Talanta 2011 v.83 no.5 pp. 1507-1514
ISSN:
0039-9140
Subject:
biocatalysis; biosensors; carbon; carbon nanotubes; detection limit; electrochemistry; electron transfer; formaldehyde; glucose; glucose oxidase; myoglobin; nanocomposites; phenol; sucrose
Abstract:
... A strategy of protein-entrapment in bicontinuous gyroidal mesoporous carbon (BGMC) nanocomposite films is described. Herein, the quasi-reversible electron transfer of redox proteins (such as glucose oxidase and myoglobin) is probed and the associated biocatalytic activity is revealed. The apparent heterogeneous electron transfer rate constant of the immobilized glucose oxidase is up to 9.4s⁻¹, muc ...
DOI:
10.1016/j.talanta.2010.11.041

4. Breath analysis by optical fiber sensor for the determination of exhaled organic compounds with a view to diagnostics

Author:
Lurdes I.B. Silva; Ana C. Freitas; Teresa A.P. Rocha-Santos; M.E. Pereira; Armando C. Duarte
Source:
Talanta 2011 v.83 no.5 pp. 1586-1594
ISSN:
0039-9140
Subject:
benzene; decane; detection limit; diagnostic techniques; disease surveillance; ethane; gas chromatography-mass spectrometry; heptane; humans; instrumentation; metabolic diseases; octane; pentane; styrene; toluene; volatile organic compounds
Abstract:
... Breath analysis constitutes a promising tool in clinical and analytical fields due to its high potential for non-invasive diagnostics of metabolic disorders and monitoring of disease status. An optical fiber (OF) sensor has been developed for determination of volatile organic compounds (ethane, pentane, heptane, octane, decane, benzene, toluene and styrene) in human breath for clinical diagnosis. ...
DOI:
10.1016/j.talanta.2010.11.056

5. Comparative evaluation of antioxidant capacities of thiol-based antioxidants measured by different in vitro methods

Author:
Nilay Güngör; Mustafa Özyürek; Kubilay Güçlü; Sema Demirci Çekiç; Reşat Apak
Source:
Talanta 2011 v.83 no.5 pp. 1650-1658
ISSN:
0039-9140
Subject:
absorbance; acetylcysteine; antioxidant activity; antioxidants; blood serum; drugs; eyes; glutathione; high performance liquid chromatography; humans; oxidation; thiols
Abstract:
... Thiol-type compounds are an important class of strong antioxidants and main determinants of total antioxidant capacity (TAC) of cellular homogenates. The TAC of thiol mixtures and the corresponding TEAC (trolox equivalent antioxidant capacity) values of individual thiols were determined by the CUPRAC (CUPric Reducing Antioxidant Capacity) method, and the results were compared with those found by r ...
DOI:
10.1016/j.talanta.2010.11.048

6. Comparison of ISO-GUM and Monte Carlo methods for the evaluation of measurement uncertainty: Application to direct cadmium measurement in water by GFAAS

Author:
Dimitrios Theodorou; Loukia Meligotsidou; Sotirios Karavoltsos; Apostolos Burnetas; Manos Dassenakis; Michael Scoullos
Source:
Talanta 2011 v.83 no.5 pp. 1568-1574
ISSN:
0039-9140
Subject:
Monte Carlo method; atomic absorption spectrometry; cadmium; least squares; mathematical models; metrology; probability distribution; uncertainty
Abstract:
... The propagation stage of uncertainty evaluation, known as the propagation of distributions, is in most cases approached by the GUM (Guide to the Expression of Uncertainty in Measurement) uncertainty framework which is based on the law of propagation of uncertainty assigned to various input quantities and the characterization of the measurand (output quantity) by a Gaussian or a t-distribution. Rec ...
DOI:
10.1016/j.talanta.2010.11.059

7. Determination and importance of temperature dependence of retention coefficient (RPHPLC) in QSAR model of nitrazepams’ partition coefficient in bile acid micelles

Author:
Mihalj Poša; Ana Pilipović; Mladena Lalić; Jovan Popović
Source:
Talanta 2011 v.83 no.5 pp. 1634-1642
ISSN:
0039-9140
Subject:
bile acids; bioavailability; hydrophobicity; least squares; linear models; micelles; permeability; quantitative structure-activity relationships; reversed-phase high performance liquid chromatography; temperature
Abstract:
... Linear dependence between temperature (t) and retention coefficient (k, reversed phase HPLC) of bile acids is obtained. Parameters (a, intercept and b, slope) of the linear function k=f(t) highly correlate with bile acids’ structures. Investigated bile acids form linear congeneric groups on a principal component (calculated from k=f(t)) score plot that are in accordance with conformations of the h ...
DOI:
10.1016/j.talanta.2010.11.050

8. Determination of uric acid and creatinine in human urine using hydrophilic interaction chromatography

Author:
Yuegang Zuo; Yang Yang; Zhuo Zhu; Wanshu He; Ziya Aydin
Source:
Talanta 2011 v.83 no.5 pp. 1707-1710
ISSN:
0039-9140
Subject:
antioxidants; biomarkers; centrifugation; colorimetry; correlation; creatinine; detection limit; filtration; humans; hydrophilic interaction chromatography; hydrophilicity; metabolism; renal function; uric acid; urine
Abstract:
... Uric acid is the end-product of purine metabolism and a major antioxidant in humans. The concentrations of uric acid in plasma and urine are associated with various diseases and routinely measured in clinical and biomedical laboratories using enzymatic conversion and colorimetric measurement. In this study a hydrophilic interaction chromatographic (HILIC) method was developed for simultaneous dete ...
DOI:
10.1016/j.talanta.2010.11.073

9. Development of metal complex imprinted solid-phase microextraction fiber for 2,2′-dipyridine recognition in aqueous medium

Author:
Jianxiang Huang; Yufei Hu; Yuling Hu; Gongke Li
Source:
Talanta 2011 v.83 no.5 pp. 1721-1729
ISSN:
0039-9140
Subject:
adsorption; binding capacity; coatings; copper; detection limit; high performance liquid chromatography; humans; molecular imprinting; pH; polymers; solid phase microextraction; solvents; tap water; urine; wastewater
Abstract:
... In this paper, a novel metal complex imprinted polymer (CIP) coated solid-phase microextraction (SPME) fiber was prepared which could recognize the complex template [Cu(OAc)₂(2,2′-dipyridine)] in aqueous medium. The saturating adsorption capacity of CIP-coated fiber was 2.2 and 2.6 times greater than those of molecularly imprinted polymer (MIP) coated fiber and nonimprinted polymer (NIP) coated fi ...
DOI:
10.1016/j.talanta.2010.12.001

10. Electrochemical impedance spectroscopy detection of lysozyme based on electrodeposited gold nanoparticles

Author:
Zhengbo Chen; Lidong Li; Hongtao Zhao; Lin Guo; Xiaojiao Mu
Source:
Talanta 2011 v.83 no.5 pp. 1501-1506
ISSN:
0039-9140
Subject:
detection limit; dielectric spectroscopy; electrodes; electron transfer; gold; iron; lysozyme; nanogold; oligonucleotides; proteins
Abstract:
... A simple, highly sensitive, and label-free electrochemical impedance spectroscopy (EIS) aptasensor based on an anti-lysozyme-aptamer as a molecular recognition element, was developed for the detection of lysozyme. Improvement in sensitivity was achieved by utilizing gold nanoparticles (AuNPs), which were electrodeposited onto the surface of a gold electrode, as a platform for immobilization of the ...
DOI:
10.1016/j.talanta.2010.11.042

11. High throughput tryptic digestion via poly (acrylamide-co-methylenebisacrylamide) monolith based immobilized enzyme reactor

Author:
Shuaibin Wu; Liangliang Sun; Junfeng Ma; Kaiguang Yang; Zhen Liang; Lihua Zhang; Yukui Zhang
Source:
Talanta 2011 v.83 no.5 pp. 1748-1753
ISSN:
0039-9140
Subject:
Escherichia coli; glutaraldehyde; immobilized enzymes; matrix-assisted laser desorption-ionization mass spectrometry; permeability; polymerization; proteins; trypsin
Abstract:
... A poly (acrylamide-co-methylenebisacrylamide) (poly (AAm-co-MBA)) monolith was prepared by thermal polymerization in the 100 or 250μm i.d. capillary. The monolithic support was activated by ethylenediamine followed by glutaraldehyde. Trypsin was then introduced to form an immobilized enzyme reactor (IMER). The prepared IMER showed a reliable mechanical stability and permeability (permeability cons ...
DOI:
10.1016/j.talanta.2010.12.011

12. Kinetic catalytic determination of trace levels of iodide based on the oxidation of basic dyes with hydrogen peroxide monitored potentiometrically using simple PVC electrodes

Author:
Elmorsy Khaled; M.A. El-Ries; F.I. Zidane; S.A. Ibrahim; M.S. Abd-Elmonem
Source:
Talanta 2011 v.83 no.5 pp. 1538-1543
ISSN:
0039-9140
Subject:
hydrogen peroxide; iodides; malachite green; methylene blue; monitoring; oxidation; phosphoric acid; specific ion electrodes; temperature
Abstract:
... Four sensitive catalytic potentiometric methods have been developed for trace levels determination of iodide based on its catalytic effects on the oxidation of four dyes: viz. variamine blue (VB), rhodamine B (RB), methylene blue (MB) and malachite green (MG), with H₂O₂ in H₃PO₄ medium at 25±0.5°C. The catalyzed reaction rates were estimated potentiometrically by monitoring the potential of the co ...
DOI:
10.1016/j.talanta.2010.11.065

13. Overall calibration procedure via a statistically based matrix-comprehensive approach in the stir bar sorptive extraction–thermal desorption–gas chromatography–mass spectrometry analysis of pesticide residues in fruit-based soft drinks

Author:
Irma Lavagnini; Alessandro Urbani; Franco Magno
Source:
Talanta 2011 v.83 no.5 pp. 1754-1762
ISSN:
0039-9140
Subject:
desorption; detection limit; gas chromatography-mass spectrometry; isotope labeling; models; organophosphorus pesticides; pesticide residues; quantitative analysis; soft drinks; uncertainty; variance
Abstract:
... Stir bar sorptive extraction (SBSE)–thermal desorption (TD) procedure combined with gas chromatography mass spectrometry (GC–MS) and the statistical variance component model (VCM) is applied to the determination of semi-volatile compounds including organochlorine and organophosphorus pesticides in various synthetic and real fruit-based soft drink matrices. When the matrix effects are corrected usi ...
DOI:
10.1016/j.talanta.2010.12.004

14. Quantification of N-acetylcysteine in pharmaceuticals using cobalt phthalocyanine modified graphite electrodes

Author:
Iranaldo Santos da Silva; Marcelo Fernando Antão Araújo; Henrique Augusto Ferreira; Jaldyr de Jesus Gomes Varela Jr.; Sônia Maria Carvalho Neiva Tanaka; Auro Atsushi Tanaka; Lúcio Angnes
Source:
Talanta 2011 v.83 no.5 pp. 1701-1706
ISSN:
0039-9140
Subject:
acetylcysteine; cobalt; detection limit; drug formulations; drugs; electrodes; flow injection analysis; graphene; quality control; sodium hydroxide
Abstract:
... Flow injection analysis (FIA) with amperometric detection was employed for the quantification of N-acetylcysteine (NAC) in pharmaceutical formulations, utilizing an ordinary pyrolytic graphite (OPG) electrode modified with cobalt phthalocyanine (CoPc). Cyclic voltammetry was used in preliminary studies to establish the best conditions for NAC analysis. In FIA-amperometric experiments the OPG–CoPc ...
DOI:
10.1016/j.talanta.2010.11.070

15. Simple spectrophotocolorimetric method for quantitative determination of gold in nanoparticles

Author:
Juliana Tournebize; Anne Sapin-Minet; Raphaël Schneider; Ariane Boudier; Philippe Maincent; Pierre Leroy
Source:
Talanta 2011 v.83 no.5 pp. 1780-1783
ISSN:
0039-9140
Subject:
absorbance; analytical methods; bromine; detection limit; gold; hydrochloric acid; nanogold; nanoparticles; oxidation; quantitative analysis; sodium chloride; transmission electron microscopy
Abstract:
... A simple spectrophotocolorimetric method devoted to the measurement of gold content in nanoparticles (NPs) was developed. It includes two steps: (i) metal gold NPs (Au NPs) are oxidized into the AuCl₄ ⁻ anion using a 5×10⁻²M HCl–1.5×10⁻²M NaCl–7×10⁻⁴M Br₂ solution, next (ii) AuCl₄ ⁻ concentration is measured using a spectrophotometric assay based on the reaction of AuCl₄ ⁻ with the cationic form o ...
DOI:
10.1016/j.talanta.2010.12.005

16. Solvent (ionic liquid) impregnated resin-based extraction coupled with dynamic ultrasonic desorption for separation and concentration of four herbicides in environmental water

Author:
Ruibing Ren; Ying Wang; Rui Zhang; Shiqian Gao; Hanqi Zhang; Aimin Yu
Source:
Talanta 2011 v.83 no.5 pp. 1392-1400
ISSN:
0039-9140
Subject:
desorption; detection limit; ethanol; high performance liquid chromatography; ionic liquids; linuron; monolinuron; pH; propazine; salt concentration
Abstract:
... A new method was developed for the determination of monolinuron, propazine, linuron, and prebane in environmental water samples. The solvent (ionic liquid) impregnated resin (IL-SIR)-based extraction coupled with dynamic ultrasonic desorption (DUSD) was applied to the separation and concentration of the analytes. The high performance liquid chromatography (HPLC) was applied to the determination of ...
DOI:
10.1016/j.talanta.2010.11.021

17. Tris(hydroxymethyl)aminomethane-modified magnetic microspheres for rapid affinity purification of lysozyme

Author:
Guoqing Zhang; Qing Cao; Na Li; Kean Li; Feng Liu
Source:
Talanta 2011 v.83 no.5 pp. 1515-1520
ISSN:
0039-9140
Subject:
binding capacity; chickens; egg albumen; lysozyme; magnetic properties; purification methods; transmission electron microscopy
Abstract:
... A novel affinity purification method for lysozyme (LZM) based on functionalized magnetic microspheres was developed. Tris(hydroxymethyl)aminomethane (Tris)-modified magnetic microspheres with specific affinity toward LZM were prepared using Tris as ligand and silica-coated magnetic microshperes as support. Transmission electron microscopy and magnetic property measurement results showed that the T ...
DOI:
10.1016/j.talanta.2010.11.040

18. Ultrasonic frequency analysis of antibody-linked hydrogel biosensors for rapid point of care testing

Author:
Jonathan R. Dion; David H. Burns
Source:
Talanta 2011 v.83 no.5 pp. 1364-1370
ISSN:
0039-9140
Subject:
acetaminophen; biosensors; blood plasma; cellulose; diagnostic techniques; hydrocolloids; polymers; saliva; spectroscopy; ultrasonics; urine
Abstract:
... Analyte quantification in highly scattering media such as tissue, blood, and other biological fluids is challenging using conventional spectroscopic methods. Ultrasound easily penetrates these opaque samples, yet currently provides little chemical information. We have developed a general approach for creating hydrogel biosensors based on antibody-linked cellulose polymers. Target recognition induc ...
DOI:
10.1016/j.talanta.2010.11.010

19. Ultrasonic quantification using smart hydrogel sensors

Author:
David Troïani; Jonathan R. Dion; David H. Burns
Source:
Talanta 2011 v.83 no.5 pp. 1371-1375
ISSN:
0039-9140
Subject:
biosensors; caffeine; correlation; electrochemistry; hydrocolloids; molecular imprinting; polymers; theophylline; ultrasonics
Abstract:
... Analyte quantification in samples with extensive matrix effects can be challenging using conventional analytical techniques. Ultrasound has been shown to easily penetrate samples that can be difficult to measure optically or electrochemically, though it provides little chemical information. Recent ultrasound contrast agents provide highly localized contrast within a sample based on concentration. ...
DOI:
10.1016/j.talanta.2010.11.009

20. Urinary signature of anabolic steroids and glucocorticoids in humans by LC–MS

Author:
Agneta Kiss; Anne-Laure Jacquet; Olivier Paisse; Marie-Magdeleine Flament-Waton; Jacques de Ceaurriz; Claire Bordes; Jean-Yves Gauvrit; Pierre Lantéri; Cécile Cren-Olivé
Source:
Talanta 2011 v.83 no.5 pp. 1769-1773
ISSN:
0039-9140
Subject:
anabolic steroids; analysis of variance; athletes; chromatography; glucocorticoids; humans; metabolomics; principal component analysis; urine
Abstract:
... A metabonomic strategy based on LC–MS was employed to investigate the metabolic profile of urine samples from 20 athletes who had been tested positive for corticoids and anabolic steroids and 29 controls. In this aim, different sample preparations and chromatographic conditions were compared. The acquired LC–MS data of doped athletes and controls were subjected to analysis of variance (ANOVA) and ...
DOI:
10.1016/j.talanta.2010.10.030