1.Residue Determination of cis-Epoxiconazole Enantiomers in Fruit and Tea by Ultra Performance Convergence Chromatography Combined with Quadrupole Time-of-Flight Mass Spectrometry
Yuechen ZHAO ; Xinzhong ZHANG ; Fengjian LUO ; Li ZHOU ; Zongmao CHEN ; Xinyi CUI
Chinese Journal of Analytical Chemistry 2016;(8):1200-1208
Abstract A chiral separation and residue determination method for cis-epoxiconazole enantiomers in apple, grape and tea samples was developed and validated by ultra performance convergence chromatography combined with quadrupole time-of-flight mass spectrometry ( UPC2-QTOF/MS) . The Chrial CCA column was used to separate cis-epoxiconazole enantiomers and the chromatography conditions ( mobile phase modifier and proportion, column temperature, automated backpressure regulator, and auxiliary solvent ) were optimized. Samples were extracted by acetonitrile, and respectively purified by Cleanert TPT or Pesti-Carb solid phase extraction ( SPE ) columns, then analyzed by UPC2-QTOF/MS. The optimum conditions were as follows:mobile phase was CO2/isopropanol (95: 5, V/V), flow-rate was 2. 0 mL/min, automated backpressure regulator (ABPR) was 13. 79 MPa, column temperature was 30℃, with a post-column mauxiliary solvent of methanol/water (1:1, V/V) containing 2 mmol/L ammonium formate. The analyte was quantified by matrix external standard method. The results showed that linear range of this method was 0. 01-1. 00 mg/L, and the correlation coefficients were above 0 . 99 . The recoveries of cis-epoxiconazole enantiomers at three spiked levels (0. 005, 0. 025 and 0. 25 mg/kg) in fruit matrix were 67. 9%-92. 8% with relative standard deviations (RSDs, n=6) less than 10%, and the limit of quantification (LOQ) of enantiomers was 0. 005 mg/kg. The recoveries of cis-epoxiconazole enantiomers at three spiked levels (0. 01, 0. 05 and 0. 5 mg/kg) in black tea were 74 . 1% -84 . 0% with RSDs ( n=6 ) less than 8%, and the LOQ for these two enantiomers was 0. 01 mg/kg. This method is rapid, convenient and reliable, and could meet the requirement of residue analysis.
2.An observation of repair of burn wound with consanguineous skin pretreated with Tripterygium wilfordii.
Guifang YOU ; Lühua LIANG ; Langsheng ZHENG ; Xinzhong LUO ; Jincai LI ; Junqi QIU
Chinese Journal of Burns 2002;18(6):372-374
OBJECTIVETo explore new source of skin for burn wound coverage.
METHODSSplit-thickness consanguineous skin was harvested from New Zealand white rabbit and was soaked in 200 g/L of multi-peptides of Tripterygium wilfordii, 50 g/L of dexamethasonel, on 9 g/L of normal saline solution for 15 - 30 mins, respectively. The consanguineous skin was thereafter grafted onto the whole layer skin defects in filial generation of rabbits with non-consanguineous skin as the control. The survival time and rejection of the grafted skin was observed.
RESULTSThe rejection appeared evidently less intense and survived significantly longer (43 +/- 3.5 days) when the consanguineous skin was pretreated by Tripterygium wilfordii. However the grafted consanguineous skin survived for 30 +/- 2.5 days when it was pretreated by dexamethasone. The grafted skin was quickly rejected and survived only for 11 +/- 1.6 days when the skin was pretreated by normal saline or the skin was non-consanguineous.
CONCLUSIONConsanguineous skin possessed partial compatibility with the recipient due to similar antigen, which was beneficial to the its survival, especially after the skin was pretreated.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Burns ; surgery ; Dexamethasone ; pharmacology ; Female ; Graft Rejection ; Graft Survival ; Male ; Plant Extracts ; pharmacology ; Rabbits ; Skin ; drug effects ; Skin Transplantation ; methods ; Transplantation, Isogeneic ; Tripterygium ; Wound Healing