Optimizing the integrated pulsed amperometric multicycle step waveform for the determination of tetracyclines.
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%.
Cai
Yu-e
YE
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Cai
Yaqi
Y
Shi
Yali
Y
Mou
Shifen
S
Lu
Yiqiang
Y
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D010118:Oxytetracycline / Q000032:analysis; D015203:Reproducibility of Results; D013754:Tetracyclines / Q000032:analysis*
D013754:Tetracyclines; D010118:Oxytetracycline