Sensitive determination of norepinephrine, synephrine, and isoproterenol by capillary electrophoresis with indirect electrochemiluminescence detection.
A new and sensitive method for the determination of norepinephrine (NE), synephrine, and isoproterenol was developed by CE separation and indirect electrochemiluminescence detection (ECL) based on their quenching effects on the tris(2,2'-bipyridyl)-ruthenium(II)/tripropylamine (TPA) system. The conditions for CE separation and ECL detection were investigated in detail. Under the optimum conditions, the three analytes were well separated within 9 min. The LODs (S/N = 3) in standard solution are 2.6 x 10(-8) mol/L for NE, 6.6 x 10(-9) mol/L for synephrine and 8.4 x 10(-8) mol/L for isoproterenol, respectively. The precisions of intraday and interday are less than 4.4 and 6.1%, respectively. The LOQs (S/N = 10) in real human urine samples are 2.6 x 10(-7) mol/L for NE, 8.8 x 10(-8 ) mol/L for synephrine, and 8.8 x 10(-7) mol/L for isoproterenol, respectively. The applicability of the proposed method was illustrated in the determination of 20 human urine samples from diabetic patients and healthy persons. The results obtained indicated that the level of NE in patients (mean value 0.41 micromol/L) was higher than that in healthy persons (mean value 0.24 micromol/L).
Liu
Yan-Ming
YM
College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang, PR China. liuym9518@sina.com
Cao
Jun-Tao
JT
Zheng
Yan-Li
YL
Chen
Yong-Hong
YH
D015082:2,2'-Dipyridyl / Q000031:analogs & derivatives; D001826:Body Fluids / Q000737:chemistry; D002021:Buffers; D003920:Diabetes Mellitus / Q000652:urine; D004563:Electrochemistry; D019075:Electrophoresis, Capillary / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007545:Isoproterenol / Q000032:analysis* / Q000652:urine; D008163:Luminescent Measurements; D009638:Norepinephrine / Q000032:analysis* / Q000652:urine; D009942:Organometallic Compounds; D011437:Propylamines; D012680:Sensitivity and Specificity; D013578:Synephrine / Q000032:analysis* / Q000652:urine
D002021:Buffers; D009942:Organometallic Compounds; D011437:Propylamines; C103599:bis(bipyridyl)ruthenium(II); C096226:tripropylamine; D015082:2,2'-Dipyridyl; D007545:Isoproterenol; D013578:Synephrine; D009638:Norepinephrine