Sonoelectrochemically enhanced determination of 5-aminosalicylic acid

The electrochemical detection of the anti-inflammatory drug 5-aminosalicylic acid (5-ASA) has been evaluated through the application of linear sweep, square wave and sonolinear sweep voltammetry. The introduction of ultrasound is shown to significantly enhance the oxidation signal intensity thereby enabling the detection of low concentrations with the linear range (1–57 μM) adequate for assessing free drug within physiological samples. Interference from ascorbic acid can be effectively negated through the introduction of cupric ion without any appreciable cost to the voltammetric response to 5-ASA. The efficacy of employing sonolinear sweep voltammetry to the determination of this compound within a compositionally complex tissue culture medium has been assessed with the recovery of 5 μM 5-ASA found to be 102% (RSD=5%, N=3).