On-Line Microfluidic Sensor Integrated with an Enzyme-Modified Pre-Cell for the Monitoring of Paracetamol in Pharmaceutical Samples

GERMÁN ALEJANDRO MESSINA; IRMA ESTER DE VITO; JULIO RABA

ANALYTICA CHIMICA ACTA

Año: 2006 vol. 559 p. 152 - 158

0003-2670

An on-line microfluidic sensing device with an enzyme-modified pre-cell coupled to an amperometric detector for the monitoring of paracetamolin pharmaceutical formulations is described. Horseradish peroxidase (HRP) [EC 1.11.1.7], immobilized on a 3 l pre-cell, in presence of hydrogenperoxide catalyses the oxidation of paracetamol to N-acetyl-p-benzoquinoneimine. The electrochemical reduction back to hydroquinone is detectedon glassy carbon electrode surface at −0.10V. The recovery of paracetamol from 10 samples ranged from 99.00 to 101.10%. This method could beused to determine paracetamol concentration in the range 0.35–100M (r = 0.997) with a limit of detection of 3.0×10−7Mand a relative standarddeviation was less than 4.1% (n = 8). The method was successfully applied for the processing of as many as 20 samples per hour of paracetamolin pharmaceutical formulations.