摘要:

The inductively coupled plasma mass spectrometry (ICP-MS), a relatively new and intensively developing instrumental method for simultaneous determination of trace elements in different matrices is reviewed. Its basic principles and experimental setting are described. The problems encountered during the analysis of clinical samples (body fluids and tissues) and their possible solutions are discussed. The sample preparation, an important part of the analysis, is reviewed. Some examples of the application of the method in the field of medicine are given.

ISSN:0003-2719    

DOI:10.1080/00032719908542986

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Polyaniline, which was electroactive in pH5.5 NaAc-HAc buffers, was used to investigate the electrochemistry of some heme proteins. The polyaniline was electropolymerized and deposited on a macro- and a micro- platinum electrode successfully. The optimum preparation method and conditions were that the polymer film was polymerized by a galvanostatic method with 35 μA/cm2current density in a 2.0 mol/L HCl solution containing 1.0 mol/L monomer under nitrogen atmosphere. The deposit amount was about 7.0 mC/cm2for the macro- and 8.5 mC/cm2for the micro- electrode. Experimental results revealed that the commonly used heme proteins, myoglobin and hemoglobin, could exhibit useful current responses at the polymer coated electrode. Since polyaniline modified electrode have a lot of virtues such as stability, good longevity, reversibility, conductivity etc., they may be useful for protein studies in the future. Another application of the polymer is, therefore, reported in this paper.

ISSN:0003-2719    

DOI:10.1080/00032719908542987

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Some basic work has been performed on the development and optimisation of superoxide dismutase (SOD) biosensors for superoxide radical analysis. Initially we studied the possibility of obtaining a SOD biosensor using the Clark electrode as indicating sensor. However, the best results were obtained using as indicator a classical amperometric electrode for H2O2. In both cases the superoxide radical was generatedin situusing the xanthine/xanthine oxidase (XOD) enzyme system, while the SOD was immobilised in kappa-carrageenan gel. The first application was realised by studying the effectsin vitroon the superoxide radical of some molecules commonly accepted as radical scavengers.

ISSN:0003-2719    

DOI:10.1080/00032719908542988

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

In the present study, conventional and synchronous luminescence (SL) were utilized to investigate spectral differences in normal and neoplastic cells. The synchronous fluorescence (SF) method involves scanning simultaneously both emission and excitation wavelengths while keeping a constant wavelength interval between them. This SF procedure simplifies the emission spectrum and provides for greater selectivity and is used to detect subtle differences in the fluorescence emission of the biochemical species of cells from rat tissues. A difference between the fluorescent spectra of the normal rat liver epithelial (RLE) and hepatoma cell lines were detected using synchronous fluorescence. The potential use of SF as a screening tool for cancer diagnosis is discussed.

ISSN:0003-2719    

DOI:10.1080/00032719908542989

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A derivative spectrophotometry was developed to determine miconazole in cream formulations that contain benzoic acid as preservative. The procedure was based on the linear relationship in the range 100-500 μg ml−1between the drug concentration and the second derivative amplitudes at 276 nm. Results of the recovery experiments performed on various amounts of benzoic acid and of the determination of miconazole in cream confirmed the applicability of the proposed method to complex formulations.

ISSN:0003-2719    

DOI:10.1080/00032719908542990

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A capillary gas chromatography (GC) method for residual solvents in the veterinary antibacterial compound sarafloxacin hydrochloride included triethylamine (TEA). Despite the use of commercially available deactivated columns and inlet liners, the peak shape and reproducibility for the TEA peak were very poor. The use of glass inlet liners and glass wool which were treated with methanolic potassium hydroxide resulted in marked improvement for TEA. This method was also used to determine residual TEA in the polypeptide GnRH.

ISSN:0003-2719    

DOI:10.1080/00032719908542991

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A sensitive and selective spectrophotometric method has been developed for the determination of six phenothiazine neuroleptics. The method is based on the interaction of the drugs with chloramine-T in sulphuric acid medium to yield a red, reddish-violet, orange or greenish-blue intermediate with maximum absorption at 500-636 nm. Beer's law is obeyed over the range 5-125 μg ml−1of the drugs. The apparent molar absorptivities were found to be in the range 1.04x103to 5.46x1031.mol−1cm−1. The investigated drugs were assayed in tablets and injections. The mean percentage recoveries were 97.65-101.75 and the relative standard deviations were found to be less than 2%.

ISSN:0003-2719    

DOI:10.1080/00032719908542992

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Derivative-Differential UV spectrophotometry and ratio-spectra first derivative spectrophotometry are presented for the simultaneous determination of analgesic and myorelaxan mixtures, namely acetaminophen (A)- phenprobamate (P). Derivative-Differential UV spectrophotometry is based on pH changes. The other method depends on the application ratio-spectra first derivative spectrophotometry to resolve the interference due to spectral overlapping.

ISSN:0003-2719    

DOI:10.1080/00032719908542993

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A simple, rapid and sensitive spectrofluorimetric method for the determination of floctafenine I (FL) in the presence of its degradation product floctafenic acid II (FLA) is developed. The method involves measuring the fluorescence intensity of FL in acetonitrile and in the presence of triethylamine (TEA) at an emission wavelength of 470 nm (excitation at 360 nm) by direct spectrofluorimetry and at an emission 465 nm (excitation 355 nm) by synchronous spectrofluorimetry. At these conditions FLA does not interfere. FLA is determined alone by measuring the fluorescence intensity of its solution in acetonitrile, without addition of TEA, at emission wavelength 460 nm (excitation 355 nm). The proposed method has been used for the assay of FL in tablets, plasma, urine and in mixtures with FLA. It gave highly accurate results for recovery of FL in the presence of its related acid.

ISSN:0003-2719    

DOI:10.1080/00032719908542994

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Ratio - spectra fourth - derivative spectrophotometry has been developed for simultaneous determination of the beta-lactam antibiotics ampicillin sodium and dicloxacillin sodium. The amplitude in the fourth derivative of ratio - spectra at 223.5 nm was selected to determine ampicillin and those at 207 and 225 nm to determine dicloxacillin.

ISSN:0003-2719    

DOI:10.1080/00032719908542995

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor