摘要:

A sensitive bioluminescent enzyme immunoassay (BLEIA) has been developed using acetate kinase(AK) as a new label enzyme. The bioluminescent assay of AK was done by firefly luciferase for measuring ATP produced by enzymatic reaction of AK using acetylphosphate and ADP as substrate. The detection limit of AK was 60 zmol/assay(1.2 amol/ml) and the coefficient of variation (CV, n=5) for each point, ranged from 2.1 to 8.3%. The proposed bioluminescent assay of AK was very simple, rapid and highly sensitive. The AK assay developed here, was applied to BLEIA of 17 α-hydroxyprogesterone, rabbit IgG and human thyroid stimulating hormone(TSH) as model compound for competitive and immunometric immunoassay.

ISSN:0003-2719    

DOI:10.1080/00032719508001104

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

This paper describes a simple procedure for treating carbon fiber electrodes. After constant potential activation and electrostatic dip modification, the electrode shows high sensitivity and selectivity for in-vivo determination of neurotransmitters. The modified electrode is only responsive to primary monoamines (DA and 5-HT) and insensitive to AA, UA and anionic metabolites. The selectivity of the electrode has been demonstrated by local microinjection and pharmacologic manipulation.

ISSN:0003-2719    

DOI:10.1080/00032719508001105

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

A polyphenol oxidase (PPO) enzyme electrode constructed by the electropolymerization of a pyrrole amphiphilic monomer-PPO mixture, previously adsorbed on a glassy carbon electrode, is applied for the direct amperometric response of phenol, 3-chlorophenol and 4-chlorophenol. Furthermore, the detection of 2-chlorophenol, several polychlorophenols and pentachlorophenol is carried out by an inhibition process of the bioelectrode functioning. The mechanism of the bioelectrode inhibition is investigated in terms of enzymatic inhibition and polymer fouling. The capacities of this system for the resolution of mixtures of phenolic pollutants are also explored on the basis of the kinetic behavior of the bioelectrode response.

ISSN:0003-2719    

DOI:10.1080/00032719508001106

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Oxalate oxidase, isolated from banana fruit peel, is immobilized on various supports and the efficacies of these derivatives in determining urinary oxalate are compared. Banana oxalate oxidase, when complexed with its antiserum, is found to have higher specific activity, greater stability, broader range of pH profile and higher resistance to thermal inactivation. Oxalate oxidase, when immobilized in acrylamide membrane strip, is found to be stable and easy to use in the determination of urinary oxalate. These two preparations compare well with that of soluble enzyme in sensitivity, accuracy and reliability. However, both hydrazide bead-linked oxalate oxidase and ethylene maleic anhydride derivative of oxalate oxidase are found to be unsuitable for the determination of urinary oxalate.

ISSN:0003-2719    

DOI:10.1080/00032719508001107

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Bilayer lipid membranes (BLMs) after suitable modofications have been reported as sensitive and selective electrochemical probes for inorganic ions. They are prepared as follows: when a metalic wire covered with a Teflon tubing has been cut in the organic phase and put into an aqueous solution, the amphiphilic lipid molecules in the solution have aligned at the interfaces of a metal/organic and organic/aqueous phases which resulted in the formation of the self-assembled solid supported bilayer lipid membranes (s-BLMs). With the modification of crown ether molecules in the s-BLMs, the membrane potentials were observed to show Nernst response to the concentration of metal cations in the range of 10−4– 10−1mol.dm−3.

ISSN:0003-2719    

DOI:10.1080/00032719508001108

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

A piezoelectric crystal sensor array has been prepared as a vapour sensing system by coating with 12 adsorptive materials selected using cluster analysis. The frequency shift data obtained from the array as the response patterns for the vapour of aliphatic alcohol homologues and isomers are treated by principal component analysis. The two-dimensional display of the original and autoscaled data show well-defined clusters for different alcohol homologues and isomers. The method has been used for discrimination of commercial beverage samples.

ISSN:0003-2719    

DOI:10.1080/00032719508001109

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Electrochemical reduction of Ketanserin was studied at different pH and concentrations using polarography and cyclic voltammetry.

ISSN:0003-2719    

DOI:10.1080/00032719508001110

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

A very simple, fast method for the spectrophotometric determination of sodium nitroprusside based on the application of kinetic methodology and the batch mixing technique to the coupling reaction between the diazotized nitroprusside derivative and N-(1-naphthyl)ethylenediamine dihydrochloride is proposed. The high initial rate of this reaction allows analytical measurements to be made within only 21 s which makes the method applicable to automatic routine analyses. The calibration graph is linear over the range 0.1–100 μg ml−1and the precision (as % RSD) is less than 1.5%. The proposed method was satisfactorily used for direct analysis of pharmaceutical formulations containing sodium nitroprusside.

ISSN:0003-2719    

DOI:10.1080/00032719508001111

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The electrochemical reduction of 2,2′-bipyridine (bipy) complexes of cobalt (II), [Co(bipy)3]2+, in aqueous medium has been studied with dc tast, normal pulse polarography and controlled-potential coulometry. The cathodic wave in the process [Co(bipy)3]2+/[Co(bipy)3]+shows catalytic character in the presence of hydrogen ions. The rate constant of the parallel chemical reaction was found to be 2.2 × 104M−1. s−1.

ISSN:0003-2719    

DOI:10.1080/00032719508001112

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The sequential determination of 14 trace metals, Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Cd, Sb and Pb, in rain and river water samples has been investigated using an inductively coupled plasma mass spectrometry (ICP-MS) with a graphite rod electrothermal vaporizer (ETV) in the presence of the mixed modifier of palladium nitrate and magnesium nitrate. The sensitivity enhancements due to the presence of the modifier were observed for all analyte elements. Detection limits as high as 0.52, 0.13, 0.89, 0.35, 1.76, 0.5, 0.9, 0.5, 0.04, 1.03, 0.28, 0.07, 0.1 and 3.78 pg, respectively, for Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Cd, Sb and Pb have been achieved. For the determination of trace metals in both rain and river water samples by this method, the repeatibility of sample solution were very good, i.e. from 1% to 7% (as a coefficient variation) and the recoveries of elements were good enough, i.e. from 81% to 106%, by using a standard addition method. There was no difference between the results obtained by nebulizer ICP-MS and those obtained by this method, except for zinc and arsenic.

ISSN:0003-2719    

DOI:10.1080/00032719508001113

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor