Determination of noradrenaline and dopamine in Chinese herbal extracts from Portulaca oleracea L. by high-performance liquid chromatography.
A simple, rapid and accurate high-performance liquid chromatographic (HPLC) technique coupled with photodiode array (PDA) detection was developed for the simultaneous determination of noradrenaline (NA) and dopamine (DA) in Chinese herbal plant extracts from the different parts of Portulaca oleracea L. The effects of various parameters, such as sodium dodecyl sulfate (SDS) concentration, pH value and proportion of methanol on chromatographic behavior of the analytes (NA and DA) were investigated. Separation of NA and DA was achieved within 10 min by a mobile phase consisting of 70% (v/v) methanol and 0.02 M potassium dihydrogen phosphate solution, which contained 30 mM SDS and was adjusted to pH 3.0 with H3PO4. NA and DA showed good linear relationships in the range of 0.004-6.00 microg and 0.011-8.25 microg respectively. The correlation coefficients of the calibration curve for the analytes exceeded 0.999. The detection limits for NA and DA were 0.40 ng and 0.55 ng, at a signal-to-noise ratio of 3, respectively. Moreover, the optimized HPLC method was employed to analyze three different parts of Portulaca oleracea L.
Chen
Juan
J
Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Road 342, Lanzhou 730000, China.
Shi
Yan-Ping
YP
Liu
Jing-Yan
JY
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004298:Dopamine / Q000032:analysis*; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D000432:Methanol; D009638:Norepinephrine / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D031822:Portulaca / Q000737:chemistry*; D015203:Reproducibility of Results; D012639:Seeds / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate
D004365:Drugs, Chinese Herbal; D007202:Indicators and Reagents; D012967:Sodium Dodecyl Sulfate; D004298:Dopamine; D009638:Norepinephrine; D000432:Methanol