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Biomedical subjects

H M Stevens

Publications and source records attributed to H M Stevens.

8 recordsLinked to original sources
PubMed1975

The recovery of alkaloids after their location on thin layer chromatograms.

A method was developed for the recovery of 29 alkaloids from TLC plates after they had been complexed with either potassium iodoplatinate (for tertiary amines) or carbon disulphide (for primary and secondary amines). A comparison was made between the percentage recoveries of these alkaloids from 5 different types of TLC plate. In addition, the stability of these alkaloids on TLC plates over a 7 day period was studied. Assays were, where possible, carried out by UV spectrophotometry but gas chromatography was used for alkaloids which possessed low UV absorbtivity values. All the alkaloids extracted from TLC plates were examined by low resolution mass spectrometry.

Alkaloids↗
PubMedDate not supplied

The recovery and identification of fluoroacetamide and fluoroacetic acid from tissues.

A rapid method is described for the extraction and identification of fluoroacetamide and fluoroacetic acid from tissues, by gas chromatography, using a mass spectrometer in the multiple ion monitoring mode as the detector. Recoveries from animal and human tissue macerates, after the addition of each compound, were approximately 30--35% for fluoroacetamide and 50--55% for fluoroacetic acid. Minimum detectable levels in tissues were found to be circa 0.7 mug/g for the amide and 0.1 mug/g for the acid. Visceral tissue levels were found to be approximately 3 mug/g for fluoroacetamide, and 2.5--10 mug/g fluoroacetic acid in guinea pigs and rabbits which had been fatally poisoned with these compounds.

Acetamides↗