Aspirin physiologically active form

Unfortunately, at this point, interpreting results for the electrode measurement of salicylate in blood samples is complicated by the fact that a large fraction of the total salicylate is bound to proteins (22, 23). The Sn(TPP)Cl2 based membrane electrode detects "free" salicylate while the conventional colorimetric procedure (i.e. the Trinder method (21) or variations thereof) measures total salicylate concentration (free plus bound). The former is the physiologically active form of the compound (24). Thus, the salicylate selective electrode could provide a new analytical tool for scientists who are examining the pharmacological effects of aspirin and other... 

Aspirin Must Be in Its Basic Form to Be Physiologically Active... 

Aspirin is a carboxylic acid. When we look at the reaction responsible for its fever-reducing, pain-reducing, and antiinflammatory properties in Section 16.11, we will see that the carboxylic acid group must be in its basic form to be physiologically active. 

Aspirin Must Be in its Basic Form to be Physiologically Active (2.10)... 

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