J. Kelly, L. Wilson
Nov 1, 1965
Citations
0
Influential Citations
2
Citations
Journal
Annals of the New York Academy of Sciences
Abstract
In the production of 6-demethylchlortetracycline, small amount,s of 6demethyltetracycline are also produced (FIGURE 1). A method of assay for 6-demethylchlortetracycline, based on the difference in the rates of conversion of these compounds to their respective anhydro forms, has been automated. Formation of anhydro is an acid catalyzed first order reaction. The degree of conversion to anhydro depends upon time, temperature and acid strength, involving a reaction which results in a decrease in absorbancy a t 368 mp and an increase in absorbancy a t 440 m ~ . ’ . ~ An AutoAnalyzer system is used to mix a blank and treatment aliquot of sample respectively with acid reagent, then to heat and cool the mixtures and to obtain readings a t 440 mp. Beckman Model “B” spectrophotometers containing the AutoAnalyzer tubular flow cell and housing are connected in series with the AutoAnalyzer colorimeters to obtain readings a t 368 mp, All data are automatically recorded on a paper punched tape by use of a Datex punchtape system for eventual calculations by a Scientific Data Systems 920 computer. A comparison was made of this procedure with the manual procedure4 which had previously been used. An estimate of the precision of this procedure was made.