Showing papers in "Analytica Chimica Acta in 1999"

TL;DR: The IUPAC nomenclature document as discussed by the authors has been prepared to help establish a uniform and meaningful approach to terminology, notation, and formulation for performance characteristics of the chemical measurement process (CMP).

TL;DR: In this article, direct electron transfer between redox enzymes and electrodes found the basis for third generation biosensors, which were used for bioelectrochemistry of redox enzyme and electrodes.

TL;DR: In this paper, the diffusion coefficients of trace metals and fulvic and humic substances in five different hydrogels were measured and the results were consistent with the known open structures of AGE and APA gels and the dependence of the structure of BPA gels on monomer concentration.

TL;DR: In this article, the authors present a review of the ISO-IUPAC deliberations and the ensuing harmonized position on concepts and nomenclature, including the meaning and evaluation of sigma, special considerations for calibration (or regression)-based detection and quantification limits, the central role of the blank, and finally some challenges for the future.

TL;DR: In this paper, the authors investigated potential sources of irreproducibility in the BCR three-stage sequential extraction procedure using the lake sediment CRM 601 and found that the pH of the hydroxylamine hydrochloride in step 2 proved most important.

TL;DR: In this paper, the analytical applications of the chemiluminescence reactions involving tris(2,2′-bipyridyl)ruthenium(III) from the earliest paper in 1978 to mid 1998 are reviewed.

TL;DR: The low K app M values demonstrated that Horseradish peroxidase immobilized on Au colloids exhibited a high affinity to H 2 O 2 with no loss of enzymatic activity.

TL;DR: In this paper, a novel chemical sensor based on a micromechanical array of silicon cantilevers is presented, which is read out using an optical beam-deflection technique by a sequential readout scheme.

TL;DR: An overview of the state-of-the-art of electrochemical biosensors employing sol-gel materials is presented in this article, along with common designs of solgel-derived bioelectrodes.

TL;DR: The principal goal of this work was to establish the feasibility of two biosensor technologies with enhanced specificity and selectivity for the detection of several bioavailable heavy metals in environmental samples.

TL;DR: The SFSTP guide as discussed by the authors suggests a validation strategy in two steps: a pre-validation and the validation itself, which is the result of a consensus between professionals having expertise in bioanalytical and/or statistical fields.

TL;DR: In this paper, two disposable electrochemical biosensors are described; the first one is useful for the detection of the hybridization of DNA and the second one is able to detect low-molecular weight compounds (toxins, pollutants, drugs) with affinity for nucleic acids.

TL;DR: A review of analytical applications of chemically modified electrodes involving zeolites or zeolite-like materials can be found in this article, where the authors classify the applications into five main categories depending on the detection process.

TL;DR: In this article, the effect of anion excluder, sodium tetraphenylborate (NaTPB), plasticizers, tris(2-ethylhexyl)phosphate (TEP), tributylphosphates (TBP), dibutylphthalate (DBP), DBBP, 1-chloronaphthalene (CN), and dioctylphthalates (DOP) on the performance of the membrane electrodes has also been studied.

TL;DR: In this paper, the basic electrochemical properties of high quality diamond thin-films (3-6μm thick) are highlighted, and the use of diamond for the voltammetric detection of trace metal ions is also illustrated.

TL;DR: The study demonstrates that oligonucleotide probes can serve as the sole counter anion during the growth of conducting PPy films, and maintain their hybridization activity within the host polymer network.

TL;DR: Stripping voltammetry is very suitable for ship-board and in-situ applications because of the portability, low cost and capability for automation of the voltammetric instrumentation as discussed by the authors.

TL;DR: In this paper, different drying (thermal, freeze-drying, chemical drying), extraction (soxhlet, sonication, KOH-digestion, mechanical shaking, supercritical fluid extraction (SFE), accelerated solvent extraction (ASE)) and detection techniques (high resolution gas chromatography-mass spectrometry (HRGC-MS), liquid chromatography−fluorescence detection (LC-FD)) were applied to real soil samples and their influence studied with respect to the final concentrations of the 16 PAHs included in the US Environmental Protection Agency Priority Poll

TL;DR: In this article, molecular imprinted polymer membranes containing artificial recognition sites for atrazine have been prepared by photopolymerisation using atrazines as a template, methacrylic acid as a functional monomer and tri(ethylene glycol) dimethacrylate as a crosslinker.

TL;DR: In this paper, two digestion procedures have been tested on plant samples for application in the determination of a wide range of major, minor, and trace elements by a combination of inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupling plasma mass spectrometer (ICP-MS).

TL;DR: In this article, the authors investigated the operational and storage stability of different tyrosinase modified electrodes, i.e., plain bulk modified carbon paste electrodes (CPEs), surface modified by simple adsorption to solid graphite electrodes (SGEs), and surfaces modified by the immobilisation in Eastman AQ, a poly ester-sulphonic acid cation exchanger, and Nafion, a perfluorinated sulphonated ionomer, on the surface of both CP and SGEs.

TL;DR: In this paper, solid phase microextraction (SPME) devices were used for a wide scope of air-monitoring including field sampling and analysis of volatile organic compounds (VOCs), formaldehyde, and particulate matter (PM) in air.

TL;DR: In this paper, a straightforward method for constructing cholesterol biosensors by entrapment of cholesterol oxidase within a polypyrrole (PPy) film electropolymerized in a flow system is proposed.

TL;DR: The neural network based algorithms (LVQ, PNN, and BP-ANN) have the highest classification accuracies and are recommended for applications where a confidence measure and fast training are critical, while speed and memory requirements are not.

TL;DR: In this paper, two kinds of chemically modified chitosan immobilizing the ligands of ethylenediamine and diethylenetriamine were prepared by interacting the anhydrides of these complexing agents with chitosa.

TL;DR: A sensitive screen-printed amperometric multielectrode biosensor for the rapid discrimination of the insecticides paraoxon and carbofuran in mixtures was developed based on the principle of acetylcholinesterase (AChE) inhibition and chemometric data analysis using artificial neural networks (ANNs).

TL;DR: In this article, the ability to accurately quantify trace pesticides and polycyclic aromatic hydrocarbons (PAHs) by EEM fluorescence spectroscopy, when coupled with parallel factor analysis (PARAFAC) deconvolution of the EEM spectra, is demonstrated and discussed.

TL;DR: In this article, a method was described for the selective extraction of mercury(II) from aqueous solutions as well as natural water samples, based on the use of four newly synthesized solid phase extractors via silica gel matrix-immobilized-iminodithiocarbamate derivatives (I-IV).

TL;DR: In this paper, a new ion exchange resin based on a UO22+ imprinted polymer was used for the removal and concentration of UO 22+ from aqueous solution prior to spectroscopic determination.

TL;DR: In this article, an apo-glucose oxidase with a ferrocene-tethered FAD-cofactor was reconstituted on the solid support to yield an aligned enzyme electrode of unprecendently efficient electrical contact.