Simple monitoring of low salicylate concentrations in capillary blood. An appraisal of ultraviolet spectrophotometric methods.

The differential ultraviolet spectrophotometric determination of salicylate according to Williams et al. (11) and the single extraction ultraviolet spectrophotometric method of Stevenson (9) are subject to interference by serotonin. Probably as a result of this interference, the results are erratic when low concentrations of salicylate are monitored in capillary blood.