Determination of 20 organochlorine pesticide residues in Gancaoxin Granule and Fuxin Tablet by GC-ECD and GC-MS respectively and comparisons between the two methods
- VernacularTitle:采用GC-ECD和GC-MS分别测定并比较甘草锌颗粒及复心片中二十种有机氯农药残留量
- Author:
Qing GUO
- Publication Type:Journal Article
- Keywords:
20 organochlorine pesticide residues(OCPs);
GC-ECD(electron capture detection);
GC-MS;
negative ion chemical ionization(NICI);
selected ions monitoring(SIM);
Gancaoxin Granule;
Fuxin Tablet
- From:
Chinese Traditional Patent Medicine
1992;0(11):-
- CountryChina
- Language:Chinese
-
Abstract:
AIM:To investigate the differences between GC-ECD and GC-MS methods which were employed in the determination of 20 organochlorine pesticide residues in Gancaoxin Granule(Radix et Rhizoma glycyrrhizae,zine preparation) and Fuxin Tablet(Folium Crataegi). METHODS: The solid-phase extraction was used for the clean-up of samples,the quartz capillary columns of DB-1701_(MS) and HP-5_(MS) were selected for the separations of target pesticides,ECD and MS were introduced as the detections respectively.N_2(99.99%,ECD) and He_2((99.999%,)MS) were used as carries,a column flow was at 1.0 mL/min,splitless was chosen as injection mode,injection amount was 1 ?L for all instances,the inlet was set at 230 ℃ and ECD at 300 ℃,negative ions-chemical ionization was used as ion source in MS,the source temperature was set at 200 ℃,the electron energy was at 100 eV,and the temperature of transfer line was at 290 ℃;methane was used as reagent gas with a flow of 3.0 mL/min,scan mode was for qualification,SIM mode was for quantitation. RESULTS: Because 20 organochlorine pesticides were impossible to be separated all on single column by an optimal temperature program to present maximum 19 peaks,on HP and column,both heptachlor-epoxide and oxy-chlordane appeared as a peak,while the overlaid peak in DB-1701 column was contributed by eicher pentachlorothioanisole and aldrin in ECD or oxy-chlordane and ?-666 in MS.We selected SIM mode in MS detection with different m/z and abundance to quantify.By a comparison,the residues of 20 organochlorine pesticides in two preparations showed higher in ECD than that in MS,except for hexachlorobenxene,trans-chlordane,pp'-DDE and endrin,the LOQs of 20 insecticides in ECD was commonly lower than that in MS. CONCLUSION: The ECD method has an advantage in sensitivity and precision,but its result on either qualification and quantitation is prone to the interferences of false positive peaks and background;while MS detection has high specificity in qualification and good accuracy in quantitation,but lower sensitivity and precision compared to ECD.Therefore,GC-ECD method for 20 organochlorine pesticide residues is sensitive and of good precision,while GC-MS method is rapid and accurate.
