title: Carbon film resistor electrode for amperometric determination of acetaminophen in pharmaceutical formulations.
abstract: Flow injection analysis (FIA) with amperometric detection was employed for acetaminophen quantification in pharmaceutical formulations using a carbon film resistor electrode. This sensor exhibited sharp and reproducible current peaks for acetaminophen without chemical modification of its surface. A wide linear working range (8.0x10(-7) to 5.0x10(-4) mol L(-1)) in phosphate buffer solution as well as high sensitivity (0.143 A mol(-1) L cm(-2)) and low submicromolar detection limit (1.36x10(-7) mol L(-1)) were achieved. The repeatability (R.S.D. for 10 successive injections of 5.0x10(-6) and 5.0x10(-5) mol L(-1) acetaminophen solutions) was 3.1 and 1.3%, respectively, without any memory effect between injections. The new procedure was applied to the analyses of commercial pharmaceutical products and the results were in good agreement with those obtained utilizing a spectrophotometric method. Consequently, this amperometric method has been shown to be very suitable for quality control analyses and other applications with similar requirements.
authors.affiliation: Instituto de Química, Universidade de São Paulo, CP 26077, 05599-970 São Paulo, Brazil.
authors.forename: Fabiana S
authors.initials: FS
authors.lastname: Felix
authors.forename: Christopher M A
authors.initials: CM
authors.lastname: Brett
authors.forename: Lúcio
authors.initials: L
authors.lastname: Angnes
mesh_terms: D000082:Acetaminophen / Q000032:analysis*; D018712:Analgesics, Non-Narcotic / Q000032:analysis*; D002021:Buffers; D002244:Carbon / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D017022:Flow Injection Analysis; D006863:Hydrogen-Ion Concentration; D019999:Pharmaceutical Solutions; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013053:Spectrophotometry / Q000379:methods; D013607:Tablets
chemical_list: D018712:Analgesics, Non-Narcotic; D002021:Buffers; D019999:Pharmaceutical Solutions; D013607:Tablets; D000082:Acetaminophen; D002244:Carbon