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Biomedical subjects

G Cavina

Publications and source records attributed to G Cavina.

At least 37 records · Page 2Linked to original sources
PubMed1979

Analysis of natural corticosteroids in adrenal extracts and in biological fluids by high-performance liquid chromatography.

A liquid chromatographic procedure is described for the analysis of the principal natural corticosteroids in extracts of adrenal glands. Microparticulate silicic acid columns and gradients of methanol in chloroform are used: conditions are described for the quantitative analysis of the single principal steroidal components of adrenal extracts for pharmaceutical use and of adrenal extracts of rats. In the last case, the use of a 5-micron silica column with the appropriate gradient allows the determination of corticosterone and of 18-hydroxydeoxycorticosterone, which were identified by means of mass spectrometry on their eluates. A single analysis can be performed on the extract of 15 mg of rat adrenal tissue. For the last type of analysis, isocratic conditions on a 10-micron LiChrosorb Diol column are also described. The application of the gradient elution procedure to the analysis of steroidal compounds in human plasma is also described.

Adrenal Cortex↗
PubMed1974

Contribution to the standardisation of a gas chromatographic method for the analysis of an oestrogenic and progestational combination.

An experimental procedure is described in order to standardize a gaschromatographic method proposed for a collaborative study organised by the F.I.P. Committee for Laboratories and Official Drug Control Services, on the analysis of some oestro-progestinic formulations. The assayed combination was a standard mixture of lynestrenol, mestranol and d, 1-alpha-tocopherol: testosterone was included as internal standard; two combinations, differing only in the internal standard content as specified in the text, were used. The variability of the instrumental factor was investigated performing some sets of single experiments, each consisting of 5 successive injections of the same standard mixture, on the same day. For each single experiment and for each substance the mean value Rm of the ratios R (R=area of the peak for compound cpi/area of the peak of the internal standard) was estimated with its relative standard deviation (% s.d.). For each set of experiments the % s.d. values were elaborated, following the Bartlett test, in order to obtain the sigma intra % value for each set, as a measure of the instrumental factor. An experimental evidence was observed for the relationship existing between the instrumental factor value (sigma intra %) and the internal standard content, in the operating conditions fixed for the present gas chromatographic analysis, a lowering of the instrumental factor beeing observed with the higher level of testosterone content (internal standard) in the mixture.

Chromatography, Gas↗