摘要:

In order to study the design features which affect the sensitivity of chemi- and bio-luminescence measuring devices, mathematical models have been devised. These models have been tested experimentally, and good agreement with their predictions obtained. Features such as dimensions of source and detector, distance from source to detector, and the use of mirrors have been investigated. This approach has provided a rational basis for the design of luminescence measuring devices.

ISSN:0003-2719    

DOI:10.1080/00032717908059765

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

One of the constituents of marijuana smoke, cannabinol, was found to photolytically decompose to one compound under nitrogen, but to three different compounds in the presence of air. The photolytic decomposition product formed under nitrogen was found to have intense fluorescent properties. Extracting saliva and irradiating the extract under nitrogen produced a detectable fluorometric change which was found to be adequate if more than 1 ng/ml of cannabinol is present in saliva.

ISSN:0003-2719    

DOI:10.1080/00032717908059766

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Two techniques were used for enriching human breath samples for δ9-tetrahydrocannabinol (I). One method utilized a polyethylene foam wafer which was positioned in front of the expired air stream using a modified face mask. The second technique was a cryogenic trap containing ethanol. Analysis of the enriched breath samples following smoking of a marijuana cigarette was accomplished using a previously described hplc-ms procedure. Results demonstrated that (I) was detectable with either enrichment method following marijuana smoking.

ISSN:0003-2719    

DOI:10.1080/00032717908059767

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A method is presented for the colorimetric assay of para-aminobenzamidine (PAB) in blood. Essentially, the PAB in trichloroacetic acid extracts is coupled to N-(l-napthyl)ethylenediamine in a typical diazotization reaction. The colored complex formed exhibits a peak absorption at 540 nm. This complex in distilled water is very stable and loses less than 5% of its absorptivity over a 24 hour period. Trichloroacetic acid extracts of whole blood containing PAB are likewise stable, exhibiting less than a 7% mean reduction in absorbance after standing for 24 hours. A plot of optical density versus concentration of the PAB diazo complex over a range of 1–20 μg/ml shows excellent linerarity. The method can accurately quantitate as little as 1 μg/ml at a dilution of 3.5.

ISSN:0003-2719    

DOI:10.1080/00032717908059768

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

An improved method for measuring Na, K-ATPase in submicrogram fragments of single renal tubules approximately one millimeter long is described. The activity is determined by coupling ATP hydrolysis stoichiometrically to pyruvate kinase and the oxidation of NADH by lactic dehydrogenase. NADH oxidation is followed fluorimetrically using an instrument specially modified for increased sensitivity and stability.

ISSN:0003-2719    

DOI:10.1080/00032717908059769

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A gas chromatographic method for the analysis of cyclophosphamide in plasma, blood, and organ tissues is described. This method involves extraction of aliquots of plasma or tissue homo-genate in alkaline condition with ether. The extracted drug is derivatized with heptafluorobutyric anhydride followed by gas chromatographic separation via a glass column of 183 cm × 2 mm i. d. packed with 3% SE-30 on chromosorb W-HP. The derivatized cyclophosphamide and isophosphamide, an added internal standard, are detected by a nitrogen-phosphorus detector. The sensitivity limit of this method is 10 ng per gm or ml of sample and gives linearity over 100-fold of concentration range.

ISSN:0003-2719    

DOI:10.1080/00032717908059770

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

An analytical method has been developed to measure Pt(II) in urine via derivatization and UV or HPLC analysis. A measured quantity of urine is heated briefly with diethyl ammonium diethyl-dithiocarbamate, and the resulting Pt(Et2NCS2)2is extracted into a measured volume of chloroform. Concentrations of Pt(II) are determined by UV absorption at 346 nm or by reverse phase HPLC analysis. The detection limit for Pt(II) as its dithiocarbamate is ∼ 1 ng by HPLC; the concentration limit for HPLC analysis by direct extraction was ∼ 25 ng/ml. Chromatographic response was linearly related to Pt(II) concentration over the range 100-4, 000 ng/ml; dilution of more concentrated samples has extended this range to at least 30, 000 ng/ml. This method has been applied to the analysis of Pt(II) in the urine of patients who have received cis-dichlorodiamniineplatinum(II) (CDDP) chemotherapy.

ISSN:0003-2719    

DOI:10.1080/00032717908059771

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

In man there are four main bile acid fractions and within each fraction there is the possibility of at least three bile acid moities - two conjugated and one unconjugated. Bile acids thus present a considerable challenge to radioimmunoassay techniques. Few of the antisera described to date are satisfactory in that they do not show equal reactivity to each of the moities to be assayed, and many have unacceptable cross reactivity properties. Clearly there is need for caution and development in this field. The first application of radioimmunoassay (RIA) techniques to the measurement of serum bile acids was made by Simmonds, Korman, Go and Hofmann in 19731. Because of its unique sensitivity and ease of application, RIA has been used not only to determine the increased serum bile acid levels found in liver disease, but also to monitor the clearance of bile acids from the peripheral circulation of normal subjects, to provide 24 hour serum bile acid profiles in normal subjects and even to assay the low serum bile acid levels found in patients in whom the bile acid enterohepatic circulation has been interrupted. Some 20 preparations of bile acid antisera have been described to date and commercial kits are now available, for RIA of each of the 4 major bile acid fractions found in human sera. Considerable differences however, in the specificity of these antisera are indicated by their reported cross reactivities and the analytical validity of their use is often questionable.

ISSN:0003-2719    

DOI:10.1080/00032717908059772

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Lead is the most frequently quantitated toxic metal in biological matrices. We describe methodologies for lead determinations in whole blood and urine using Zeeman effect flameless atomic absorption spectroscopy. The whole blood determination requires a simple aqueous 1:10 dilution while the urine lead methodology utilizes a twofold dilution with 5% nitric acid. Within-run relative standard deviations (RSD) for the whole blood determination are approximately 4. 9%, while urine lead within-run PSD's are approximately 6.7%. Detection limits for both the whole blood lead determination and the urine lead determination are 3 ppb. Linearity for both assays is to 200 ppb in the diluted specimens.

ISSN:0003-2719    

DOI:10.1080/00032717908059773

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Carbamazepine, a tricyclic antidepressant, has been assayed in its tablets (Tegretol ®) by the application of PMR spectrometry. The proposed method involves comparing the integral of the aromatic and olefinic protons of carbamazepine, in the range 6.60 -7.60 ppm, to that of the singlet of a known amount of hexamethylcyclotrisilazane (at 0.00 ppm) used as internal standard. The method is simple, rapid and accurate. The average percent recovery, of carbamazepine from its tablets, is 96.88 ± 0.93. In addition, the PMR spectrum obtained helps in checking the identity and purity of the drug extracted from its pharmaceutical preparation.

ISSN:0003-2719    

DOI:10.1080/00032717908059774

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor