1.Rapid Determination of 25 Kinds of Fungicides in Cereals, Fruits and Vegetables by Solid Phase Extraction and Liquid Chromatography Coupled with Quadrupole-Time of Flight Mass Spectrometry
Chunyan CUI ; Hongyi ZHANG ; Xingqiang WU ; Chunlin FAN ; Guofang PANG
Chinese Journal of Analytical Chemistry 2017;45(8):1195-1202
A method for simultaneous determination of 25 kinds of fungicides in cereals, vegetables and fruits using SPE-LC-Q-TOF/MS technique was developed.The samples were extracted with acetonitrile containing 1% (V/V) acetic acid, purified by solid phase extraction (SPE) with a Crabon/NH2 cartridge, eluted with acetonitrile-toluene(3∶1, V/V), separated by a reversed phase C18 column, gradiently eluted with acetonitrile and 0.1% formic acid solution (Containing 5 mmol/L ammonium acetate), determined by LC-Q-TOF/MS, and quantified by external standard method.A data base of the accurate mass numbers and a library which contains 25 kinds of fungicides were established.The automatic retrieval of detection results was carried on according to the characteristics of the compound, such as accurate mass, retention time, isotope peak distribution, isotopic ratios, and so on.Based on the above results, the qualitative identifications of the 25 new fungicides were accomplished without the contrast of standard substances.The results indicated that 25 fungicides showed good linearity in the range of 0.02-200 μg/L, and the limits of detection (LOD) and the limits of quantification (LOQ) were 0.01-5.00 μg/kg and 0.02-20.00 μg/kg, respectively.The linear relative coefficients were greater than 0.995.The recoveries were in the range 71.8%-114.0% and the relative standard deviations (RSD) were ranged from 0.1% to 21.3% (n=3).The method has some advantages such as simplicity, rapidity and high sensitivity, and is suitable for the rapid determination of the common fungicides in cereals, vegetables and fruits.
2.Identification and comparison of constituents in HPLC fingerprint of five Chinese herbal pieces from Rheum palamatum.
Li LI ; Cun ZHANG ; Yongqing XIAO ; Na LIN ; Chunfang LIU ; Zhen PANG ; Guiliu LI ; Dongdong CHEN ; Guofang TIAN
China Journal of Chinese Materia Medica 2009;34(13):1668-1671
OBJECTIVETo identificate and compare constituents in the HPLC fingerprint of five Chinese herbal pieces from Radix et Rhizoma Rhei.
METHODHPLC analysis was carried out with methyl alcohol 1% glacial acetic acid as gradient elution, changes in five Chinese herbal pieces and medicinal material under 280 nm and 430 nm were compared.
RESULTHPLC fingerprints of the no-parched pieces, the liquor and the vinegar roasts pieces were similar, 24 peaks were identified under 280 nm 19 or 22 peaks could be indicated in the braising with liquor and the charring respectively. Under 430 nm, 8 peaks were identified except the braising with liquor.
CONCLUSIONHPLC fingerprints of the no-parched pieces, the liquor and the vinegar roasts pieces are similar while the changes on chemical composition and the content in braising with liquor and the charring are remarkable.
Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; analysis ; Rheum ; chemistry
3.Anthraquinone contents in five processed products from Rheum palamatum.
Cun ZHANG ; Li LI ; Yongqing XIAO ; Na LIN ; Chunfang LIU ; Guiliu LI ; Zhen PANG ; Dongdong CHEN ; Guofang TIAN
China Journal of Chinese Materia Medica 2009;34(15):1914-1916
OBJECTIVETo compare the contents of five anthraquinone components in five different processed products from Rheum palamatum.
METHODThe contents of aleo-emodin, rhein, emodin, chrysophanol and physcion were determined simultaneously by HPLC on plogilent TC-C18 (2) column at 35 degrees C with the methanol-0.1% phosphoric acid (85: 15). The detection wavelength was set at 254 nm and the flow rate was 1.0 mL x min(-1).
RESULTThe obtained linearity of the five components was better over 0.999 9 and the average recoveries were 96.44%, 98.11%, 99.30%, 98.00% and 97.86%, respectively.
CONCLUSIONThe results showed the remarkable variation regulations show in the five different processed products. Compared to the no-parched pieces, the contents of the five anthraquinone components have evidently increased in the braising with liquor and the charring products, and reduced in the vinegar and the liquor sauted pieces.
Anthraquinones ; analysis ; Pharmaceutical Preparations ; analysis ; Rheum ; chemistry