Flow-injection analysis with multiple-pulse amperometry for simultaneous determination of paracetamol and naproxen using a homemade flow cell for screen-printed electrodes

• Main Author: Stefano,Jessica S.
• Publication Date: 2014
• Other Authors: Montes,Rodrigo H. O., Richter,Eduardo M., Muñoz,Rodrigo A. A.
• Format: Article
• Language: eng
• Source: Journal of the Brazilian Chemical Society (Online)
• Download full: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532014000300011
• topic: carbon nanotubes; pharmaceutical formulations; flow analysis; acetaminophen; non-steroidal anti-inflammatory drug

This work reports the simultaneous determination of paracetamol and naproxen using multiple-pulse amperometric detection on a multi-walled carbon nanotube modified screen-printed electrode (MWCNT-SPE) adapted in a homemade flow-injection analysis (FIA) cell. A sequence of two potential pulses (+0.30 and +0.70 V for 70 ms each) was applied continuously in such a way that paracetamol is selectively oxidized at +0.30 V and both compounds (paracetamol and naproxen) are oxidized at +0.70 V. Current subtraction after using a correction factor was employed for determination of naproxen without the interference of paracetamol. The proposed FIA method presents high selectivity and sensitivity, adequate accuracy (results in agreement with high-performance liquid chromatography), elevated analytical frequency (90 h-1), and low-cost once a single SPE strip can be used during the whole working day adapted in a flow-cell.