Flow-injection chemiluminescence determination of catecholamines based on their enhancing effects on the luminol-potassium periodate system.
A rapid and sensitive chemiluminescence (CL) method using flow injection analysis is described for the determination of four catecholamines, dopamine, adrenaline, isoprenaline and noradrenaline, based on their greatly enhancing effects on the CL reaction of luminol-potassium periodate in basic solutions. The optimized chemical conditions for the chemiluminescence reaction were 1.0 x 10(-4) mol/L luminol and 1.0 x 10(-5) mol/L potassium periodate in 0.2 mol/L sodium hydroxide (NaOH). Under the optimized conditions, the calibration graphs relating the CL signal intensity (peak height) to the concentration of the analytes were curvilinear and they were suitable for determining dopamine, adrenaline, isoprenaline, and noradrenaline in the range 0.1-10 ng/mL, 0.1-100 ng/mL, 1-100 ng/mL and 5-50 ng/mL, respectively, with the relative standard deviations of 0.8-1.7%. The detection limits of the method are 0.02 ng/mL for dopamine, 0.01 ng/mL for adrenaline, 0.1 ng/mL for isoprenaline and 2.0 ng/mL for noradrenaline. The sampling frequency was calculated to be about 60/h. The selectivity of the method was good, because a series of common ions or excipients, such as K(+), Ba(2+), CO(3)(2-), NO(3)(-), SO(4)(2-), PO(4)(3-), sodium citrate, sodium bisulphite, oxidate dopamine, starch, lactose, carbamide and gelatin, could not produce interference when their concentrations were 1000-fold than those of dopamine. The present method was successfully applied to the determination of the four catecholamines in pharmaceutical injections.
Yao
Hong
H
Department of Pharmaceutical Analysis, School of Pharmacy, Fujian Medical University, Fuzhou 350004, People's Republic of China. yaosyy@sina.com
Sun
Yuan Yuan
YY
Lin
Xinhua
X
Cheng
Jinghua
J
Huang
Liying
L
D002395:Catecholamines / Q000032:analysis*; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods; D049449:Luminescence; D008163:Luminescent Measurements / Q000379:methods*; D008165:Luminol / Q000737:chemistry*; D010504:Periodic Acid / Q000737:chemistry*; D011188:Potassium / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012972:Sodium Hydroxide / Q000737:chemistry
D002395:Catecholamines; D010504:Periodic Acid; D012972:Sodium Hydroxide; D008165:Luminol; D011188:Potassium