Easton’s syrup

The various salts of quinine are incorporated into a number of official preparations such as syrups and tablets. The simpler formulations can be assayed by a spectrophotometric method based upon the absorption characteristics in the ultra-violet. For example, in N sulphuric acid, quinine hydrochloride has two absorption maxima at 250 m/i and 347 m/, the E(1 per cent, 1 cm) values being about 730 and 140 respectively. However, this technique is not applicable to the more complex samples such as Easton s Syrup or Tablets without first extracting the quinine and a... 

To determine the alkaloids quinine and strychnine, proceed as for Easton s Syrup (Nux Vomica, p. 469). 

The alkaloids must be removed from Easton s Syrup ... 

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