title: Optimizing the integrated pulsed amperometric multicycle step waveform for the determination of tetracyclines.
abstract: A method of modified integrated pulsed amperometric detection with multicycle step waveform (Multi-IPAD) following high-performance liquid chromatography (HPLC) was applied for the determination of tetracyclines (TCs) including dimethyltetracycline (DMTC), oxytetracycline (OTC) and tetracycline (TC). The key advantages of the Multi-IPAD are the abilities to enhance sensitivity and reproducibility and the ability to keep working electrode clean through the use of a high-frequent waveform alteration in integration step and the use of a cleaning potential, which is quite different from conventional three-step potential waveform. The analyses were carried out using the mobile phase of acetonitrile-water mixture solution (10:90, v/v) containing 1% perchloric acid on a C(18) column at a flow rate of 0.21 mL/min. The IPAD waveform parameters were optimized to maximize the signal-to-noise ratio (S/N) and successfully applied for the sensitive detection of TCs. The detection limits (S/N=3, 20 microL injected) were 0.07 mg/L for DMTC, 0.08 mg/L for OTC and 0.05 mg/L for TC. The peak height relative standard deviations (RSDs) of every compound for replicate injection (n=15) determined were below 4.6%.
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Yu-e
authors.initials: YE
authors.lastname: Cai
authors.forename: Yaqi
authors.initials: Y
authors.lastname: Cai
authors.forename: Yali
authors.initials: Y
authors.lastname: Shi
authors.forename: Shifen
authors.initials: S
authors.lastname: Mou
authors.forename: Yiqiang
authors.initials: Y
authors.lastname: Lu
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D010118:Oxytetracycline / Q000032:analysis; D015203:Reproducibility of Results; D013754:Tetracyclines / Q000032:analysis*
chemical_list: D013754:Tetracyclines; D010118:Oxytetracycline