The quantitative analysis of paraquat in biological samples by liquid chromatography-electrospray ionization-mass spectrometry.

A quantitative method for the analysis of paraquat in blood and tissue samples has been developed using liquid chromatography-electrospray ionization-mass spectrometry. Chromatographic separation was performed on an Atlantis HILIC silica column using a mobile phase of acetonitrile/250 mM ammonium formate in the gradient mode. The method was linear from 2 to 500 ng/mL, with a correlation coefficient of 0.998. The limits of detection and quantitation in blood were determined to be 0.5 and 2 ng/mL, respectively. Intraday precision was performed in one extraction by analyzing five aliquots of three controls with different concentrations in the established linear range. Interday precision was determined by analyzing one aliquot of each control over 10 extractions. The coefficients of variation were less than 10% for both intra- and interday assays. The method has been successfully applied to blood and tissues samples from nine cases and can be used to detect the presence of paraquat in forensic testing.

Quantitative determination of diterpenoid alkaloids in four species of Aconitum by HPLC.

A high performance liquid chromatography (HPLC) method has been developed for the determination of five principal alkaloids (benzoylmesaconine, mesaconitine, aconitine, hypaconitine and deoxyaconitine) found in four species of genus Aconitum. The five alkaloids were analyzed simultaneously with an XTerraRP18 column by gradient elution using 0.03 M ammonium hydrogen carbonate-acetonitrile as mobile phase. The recovery of the method was 94.6-101.9%, and all the alkaloids showed good linearity (gamma = 0.9999) in a relatively wide concentration range. The results indicated that contents of alkaloids in Aconitum varied significantly from species to species; hence quality control of Aconitum drugs is very necessary.

Determination of triptolide and triptonide in human plasma by high-performance liquid chromatography.

An isocratic high-performance liquid chromatographic method for determination of triptolide and triptonide in human plasma is described. Plasma samples were extracted with OasisHLB solid-phase extraction (SPE) cartridges. After pretreatment, they were separated on a SymmetryShieldRP(18) column with a mobile phase of acetonitrile-water (40:60,v/v) at 40 degrees C. The effluent was monitored at UV 217 nm. Linearity (0.010-1.0 mg/L) was good, and the lower limit of detection was 3 ng/mL for triptolide and 4.5 ng/mL for triptonide (S/N = 3). The relative standard deviations of intra- and inter-day assay were less than 15% and the recoveries were better than 80%. The developed method was applied to the determination of triptolide and triptonide concentration in a patient's plasma after taking the medicament containing Tripterygium wilfordii Hook. F.

Analysis of strychnine and brucine in postmortem specimens by RP-HPLC: a case report of fatal intoxication.

A sensitive method for the identification and quantitation of the toxic alkaloids strychnine and brucine from postmortem specimens has been established. After solid-phase extraction using Oasis MCX cartridges the extracts were analyzed by high-performance liquid chromatography with diode-array detection. The limit of detection was 0.5 ng/mL blood for strychnine and brucine, and the limit of quantitation was 5 ng/mL blood for strychnine and brucine. The method was applied for the analysis of blood and gastric contents of a 34-year-old female who died after ingestion of a packet of herbal medicine powder containing the seeds of Strychnos nux-vomica L. Strychnine and brucine were detected in all the samples. The concentration in our case is consistent with that in previous reports.

[Analyses on the trace elements of soils in geo-authentic and non-authentic production areas of Flos lonicearae].

OBJECTIVE: To analyse the trace elements presented in the same germplasm of Flos Lonicerae with the soil in different producing areas of crude drugs and to investigate, the relationship between the trace elements and the characteristics of the geo-authentic Flos Lonicerae in the soil and crude drugs. METHOD: The analyses on the trace elements of soil and crude drugs were made by ICP-AES. RESULT: The contents of Sr, K, Na, Mg and Ca were higher in the geo-authentic areas, and the contents of Ca, Sr and Fe were higher, but the Cr and Pb were lower in the geo-authentic Flos Lonicerae. The geo-authentic crude drugs had a strong tendency to accumulate P and Cu. CONCLUSION: There are no direct relationship between the concentrations of trace elements in Flos Lonicerae and those in their corresponding soil. There are good relationship between the absorption and accumulation of Ca and Cr, Co, Na and Fe; Zn and Co, Cr, Mn; Na and Co; Mg and Mn.

[Studies on the floral morphology of Flos Lonicerae].

Pollen grains, petal, corolla tube and stigma of two species of Flos Lonicerae from 11 habitats in China were examined by the light microscope (LM) and scanning electron microscope (SEM). The difference between the species, Lonicera japonica and L. hypoglauca, existed in the pollen grains, colporates, exines and the omamentations. Characteristics obviously varied in different species and were closely related to geographic distribution among the species. The results might provide a scientific basis for the quality evaluation of Genuine Crude Drug, and for the identification of varieties.

[Determination of quercetin in the Herba Euphorbiae Humifusae].

OBJECTIVE: To develop an HPLC method for determining quercetin in Herba Euphorbiae Humifusae. METHOD: ODS column was used with acetonitrile: 0.4% phosphoric acid (40:60) as mobile phase. The detection wavelength was at 370 nm and the flow rate was 1.0 mL.min-1. RESULT: The linearity was obtained over the range of 0.0364-0.1274 microgram (r = 0.9999). The average recovery was 100.71% with relative standard deviation of 2.45%. CONCLUSION: This method can be used for quality control of Herba Euphorbiae Humifusae. It is simple, rapid and reliable.