Simultaneous determination of cadaverine and putrescine using a disposable monoamine oxidase based biosensor

The selective and simultaneous amperometric determination of putrescine (Put) and cadaverine (Cad) has been carried out using a novel design of screen-printed carbon electrode (SPCE) with two working electrodes connected in array mode. A mixture of 3% of tetrathiafulvalene (TTF), as mediator, and carbon ink was used for the construction of the screen-printed working electrode. The employment of different amounts of monoamine oxidase (MAO) enzyme on these modified TTF/SPCEs and the use of gold nanoparticles (AuNPs) allowed performing the simultaneous determination of both analytes. The amperometric detection has been performed by measuring the oxidation current of the mediator at a potential of+250mV vs. screen-printed Ag/AgCl reference electrode. A linear response in the Cad concentration range from 19.6 till 107.1µM and from 9.9 till 74.1μM for Put was obtained at the MAO/AuNPs/TTF/SPCE biosensor. This device showed a capability of detection of 9.9 and 19.9±0.9µM (n=4 α=β=0.05) and a precision of 4.9% and 10.3% in terms of relative standard deviation for Put and Cad, respectively. The developed biosensor was successfully applied to the simultaneous determination of Put and Cad in octopus samples. Chronoamperograms recorded for the simultaneous determination of Put and Cad using an array-TTF/SPCEs biosensor. (1) Working 1: MAO/TTF/SPCE and (2) working 2: MAO/AuNPs/TTF/SPCE. [Display omitted] •Simultaneous determination of Put and Cad on MAO based biosensors using SPCEs.•High degree of sensitivity in the analysis of Put and Cad.•Application to the simultaneous analysis of Put and Cad in complex samples.