strychnine and formic-acid

To establish a LC-MS/MS method which is accurate and sensitive for determination of koumine, gelsemine, and gelsenicine in biological samples and to verify the method.. Strychnine was used as internal standard. Analytes in blood, urine and liver with 1% sodium hydroxide solution were extracted by ethyl acetate. Chromatographic separation was achieved on a ZORBAX SB-C₁₈ column （150 mm×2.1 mm, 5 μm）, and gradient elution was performed with the buffer solution of methanol-20 mmol/L ammonium acetate （including 0.1% formic acid and 5% acetonitrile） as mobile phase. Qualitative and quantitative analysis was performed in the multiple reaction monitoring mode coupled with an electrospray ionization source under positive ion mode（ESI⁺）.. The method is selective, sensitive and suitable for simultaneous determination of koumine, gelsemine and gelsenicine in body fluids and tissues, which offering technical support for clinical diagnosis and treatment and forensic toxicological analysis of

Topics: Alkaloids; Chromatography, High Pressure Liquid; Chromatography, Liquid; Forensic Toxicology; Formates; Humans; Indole Alkaloids; Liver; Reproducibility of Results; Strychnine; Tandem Mass Spectrometry

To establish a method for determination of strychnine and brucine in formaldehyde fixed tissue by LC-MS/MS analysis.. The samples were pretreated with solid phase extraction using SCX cartridges and separated on SB-C18 column with mobile phase 0.1% formic acid : 0.1% formic acid-acetonitrile (75:25). Electrospray ionization (ESI) source was utilized and operated in positive ion mode. Multiple reactions monitoring (MRM) mode was applied. External standard method was applied for quantitation.. The chromatographic separation of strychnine and brucine in formaldehyde fixed nephritic and hepatic tissues resulted successfully. The standard curve was linear in the range of 0.002-2.0 microg/g for strychnine and brucine in formaldehyde fixed tissues, and the correlation coefficient was more than 0.996. The limits of detection (LOD) of strychnine and brucine in nephritic tissues were 0.06ng/g and 0.03 ng/g, respectively. The LOD of both chemicals were 0.3 ng/g in hepatic tissues. The extraction recovery rate was more than 74.5%. The precision of intra-day and inter-day were both less than 8.2%.. Strychnine and brucine can be sensitive to be determined in formaldehyde fixed tissue by LC-MS/MS analysis. It can be applied in the forensic toxicological analysis.

Topics: Chromatography, Liquid; Forensic Toxicology; Formaldehyde; Formates; Kidney; Limit of Detection; Liver; Mass Spectrometry; Molecular Structure; Reproducibility of Results; Spectrometry, Mass, Electrospray Ionization; Strychnine; Tandem Mass Spectrometry; Tissue Distribution

A simple, sensitive and selective liquid chromatography-electrospray mass spectrometric (LC-ESI-MS) method was developed and validated for simultaneous determination of strychnine and brucine in rat plasma, using tacrine as the internal standard (IS). Sample preparation involved a liquid-liquid extraction of the analytes with n-hexane, dichloromethane and isopropanol (65:30:5, v/v/v) from 0.1mL of plasma. Chromatographic separation was carried out on a Waters C(18) column using a mobile phase of methanol-20mM ammonium formate-formic acid (32:68:0.68, v/v/v). Positive selected ion monitoring mode was used for detection of strychnine, brucine and the IS at m/z 335.2, m/z 395.2 and m/z 199.2, respectively. Linearity was obtained over the concentration range of 0.5-500ng/mL for strychnine and 0.1-100ng/mL for brucine. The lower limit of quantification was 0.5ng/mL and 0.1ng/mL for strychnine and brucine, respectively. The intra- and inter-day precision for both strychnine and brucine was less than 7.74%, and accuracy ranged from -4.38% to 2.21% at all QC levels. The method has been successfully applied to a pharmacokinetic study of processed Semen Strychni after oral administration to rats.

Topics: 2-Propanol; Animals; Calibration; Chromatography, Liquid; Dose-Response Relationship, Drug; Formates; Hexanes; Male; Methanol; Methylene Chloride; Molecular Structure; Quality Control; Rats; Rats, Wistar; Reference Standards; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization; Strychnine; Time Factors