摘要:

Antibodies are studied in terms of their properties as molecular recognition elements using an antigen monitoring biosensor as a means of examining sensitivity and selectivity. This approach requires only a small amount of antibody for study and is illustrated for a model system in which two monoclonal antibodies and one polyclonal antibody to 2,4-dinitrophenol are compared on the basis of their association constants and cross-reactivity patterns with heterologous haptens.

ISSN:0003-2719    

DOI:10.1080/00032718808059883

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

There is a need to expand the range of working electrodes which can be us in analytical voltammetry.

ISSN:0003-2719    

DOI:10.1080/00032718808059884

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A procedure for study of the effects of the temperature on the response of ion-selective electrodes in which isothermal hysteresis cum determined at several concentrations are used for obtaining the temperature variation parameters (isothermal slope and potential coefficients and isopotential points) is proposed. The procedure was tested against the classic procedure in which calibration curves are obtained at different temperatures. 'All -solid-state' Ag2S and Ag2S/Agl electrodes with sensors applied to silver- and copper-loaded epoxy supports (and commercial electrodes, for comparison) were used for this purpose. The values of the temperature parameters obtained by the two procedures (in the raw 10–60°C) are compared. This comparison show that the present procedure yields acceptable values of temperature parameters for cases like the studied where the hysteresis is not very produced.

ISSN:0003-2719    

DOI:10.1080/00032718808059885

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Wet ashing of whole fish arid standard mammalian liver samples for metal determinations is effectively achieved through low power pulse microwave treatment using a domestic grade microwave oven. The reaction is carried out in an open Erlenmeyer flask while held within a much larger sealed container. The latter may be any inexpensive vessel that is microwave proof. The power setting is approximately 70 watts. The oven is programmed to deliver microwaves for 10 seconds every three minutes for a total of 19 minutes. Efficiency of recovery is generally within 10% of the known amounts. The pulse microwave protocol avoids the high temperatures and pressures that create the risk of explosions.

ISSN:0003-2719    

DOI:10.1080/00032718808059886

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A new spectrophotometric determination of cobalt with 2-hydroxy-1-naphthaldehyde guanylhydrazone in acid medium is described. The method is developed on the basis of a yellow cobalt (III) complex (molar absorptivity 1.32×10−4L.mol−1.cm−1at 416 nm, stoichiometry 2:1). The method was applied to the determination of cobalt in vitamin preparations, steel and high-purity iron.

ISSN:0003-2719    

DOI:10.1080/00032718808059887

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Lytic peptides such as melittin and mastoparan are usually assayed by measuring the leakage of cell contents; e.g., hemolysis. When such peptides lyse liposomes containing concentration-quenched 6-carboxyfluorescein (6CF), the resulting fluorescence increase is proportional to the amount of lytic peptide added. Using this 6CF-liposome system, one can assay nanogram quantities of melittin. A protocol was developed to survey peptides for lytic activity and at the same time, to test for mast cell degranulating activity. Peptides possessed either, both, or neither of these activities. The dye-liposome system was used to assay HPLC fractions of bee venom. This fluorescence assay for lytic activity is more sensitive and convenient than the hemolysis method, does not require removal of unlysed structures, and does not require animal cells.

ISSN:0003-2719    

DOI:10.1080/00032718808059888

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A novel and sensitive enzyme immunoassay for anti-thyroglobulin antibodies is described. Anti-thyroglobulin antibodies in test serum were reacted simultaneously with dinitrophenyl thyroglobulin and thyroglobulin-horseradish peroxidase conjugate. The complex formed of anti-thyroglobulin antibodies, dinitrophenyl thyroglobulin and thyroglobulin-peroxidase conjugate was trapped onto two affinity-purified rabbit (anti-dinitrophenyl bovine serum albumin) IgG-coated polystyrene balls. Peroxidase activity bound to the polystyrene balls was assayed by fluorimetry using 3-(4-hydroxyphenyl)propionic acid as substrate. This assay was more sensitive than the conventional enzyme immunoassays, and anti-thyroglobulin antibodies were demonstrated in part of healthy subjects and in all patients with Graves' disease and chronic thyroiditis.

ISSN:0003-2719    

DOI:10.1080/00032718808059889

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The interactions of aqueous solutions of chlorine with some fruit acids (citric acid, DL-malic acid, arid L-tartaric acid) at different pH values were studied. Diethyl ether extraction followed by GC/MS analysis indicated that a number of mutagens (certain chlorinated propanones and chloral hydrate) are present as major products in some of these samples. A number of fruit juices (orange, grape, apple, pineapple, and grapefruit) were also treated with aqueous solutions of chlorine at their pH values. The products were analyzed by GC/MS. The same mutagens that were formed by the pure acids (citric acid and DL-malic acid) were identified as major products in ether extracts of these samples. Another mutagen, dichloroacetonitrile, was also identified as a minor product in some of these juice samples. All of the major products observed in the chlorination of all five fruit juices are potentially derived from reactions of aqueous solutions of chlorine with citric or malic acid and with trace amounts of acetaldehyde and acetone in the juices. The minor product, dichloroacetonitrile, is likely derived from the chlorination of certain amino acids in the fruit juices.

ISSN:0003-2719    

DOI:10.1080/00032718808059890

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Most linear regression problems involving prediction or estimation require determining the Y value corresponding to a given X. The calibration problem (or inverse estimation or discrimination) is the inverse of the above situation in that we have a given value of Y and we want to determine X. This paper will document the various statistical approaches to this problem and do a numerical example using the classical estimator.

ISSN:0003-2719    

DOI:10.1080/00032718808059891

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A fluorometric method to determine the kinetics of the uptake and metabolism of a p-halohydroxybenzonitrile herbicide has been developed using variable chlorophyllafluorescence. Bromoxynil inhibits photosynthetic electron transport and results in large variable chlorophyllafluorescence yields. Lethal and sub-lethal doses of bromoxynil were applied to two maize genotypes. Measurement of variable chlorophyllafluorescence over several hours revealed the uptake and detoxification of bromoxynil by the appearance and disappearance of inhibited fluorescence transients. A difference in bromoxynil susceptibility was observed between inbreds B73 and OH43 in these preliminary studies. Also observed was a difference in susceptibility between the oldest and second oldest leaves of these maize seedlings. Variable chlorophyllafluorescence has the potential to be a rapid, non-destructive analytical method for observing the biochemical metabolism of herbicides in plants.

ISSN:0003-2719    

DOI:10.1080/00032718808059892

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor