RESUMO
Monolithic silica spin column extraction (MonoSpin-SPE) was developed as a simple,sensitive,and eco-friendly pretreatment method which combined with ultra-fast liquid chromatography-mass spectrometry (UFLC-MS) to determine the levels of six phthalate esters,dimethyl-(DMP),diethyl-(DEP),dipropyl-[DPrP],butyl-benzyl-(BBP),dicyclohexyl(DcHP),and di-n-octyl-(DOP) phthalate in physiological saline samples.Under optimized experimental conditions,the method was linear in the following ranges:0.2 - 50 μg/L for DMP,DEP,DPrP,DcHP and DOP; 5- 100,μg/L for BBP.The correlation coefficients (R2 ) were in the range of 0.9951- 0.9995 for all the analytes and the limits of detection (LODs) and limits of quantification (LOQs) were in the ranges of 0.02- 0.9 μg/L and 0.08- 2.7 μg/L,respectively.The pretreatment process showed good reproducibility with inter-day and intra-day relative standard deviations (RSDs) below 8.5％ and 11.2％,respectively.This method was used to determine the levels of six phthalate esters in physiological saline samples and the recoveries ranged from 71.2％ to 107.3％.DMP and DEP were found in actual physical saline samples (brand A and brand B).
RESUMO
Monolithic silica spin column extraction （MonoSpin-SPE） was developed as a simple, sensitive, and eco-friendly pretreatment method which combined with ultra-fast liquid chromatography-mass spectrometry （UFLC-MS） to determine the levels of six phthalate esters, dimethyl- （DMP）, diethyl- （DEP）, dipropyl- [ DPrP], butyl-benzyl- （BBP）, dicyclohexyl- （DcHP）, and di-n-octyl-（DOP） phthalate in physiological saline samples. Under optimized experimental conditions, the method was linear in the following ranges： 0.2- 50 μg/L for DMP, DEP, DPrP, DcHP and DOP; 5- 100 μg/L for BBP. The correlation coefficients （R2 ） were in the range of 0. 9951 - 0. 9995 for all the analytes and the limits of detection （LODs） and limits of quantification （LOQs） were in the ranges of 0.02 - 0.9 μg/L and 0.08 - 2.7μg/L, respectively. The pretreatment process showed good reproducibility with inter-day and intra-day relative standard deviations （RSDs） below 8.5% and 11.2%, respectively. This method was used to determine the levels of six phthalate esters in physiological saline samples and the recoveries ranged from 71.2% to 107.3%. DMP and DEP were found in actual physical saline samples （brand A and brand B）.
RESUMO
Preconcentration of catecholamines by the modified monolithic silica in the capillary was investigated in this study. In order to achieve a microchip-based method for determining catecholamines in the saliva, the monolithic silica was fabricated in the capillary and the monolithic silica was chemically modified by on-column reaction with phenylboronate. Different modified methods were compared. The concentration conditions were optimized. This study indicates the applicability of the modified monolithic silica capillary when it was used to concentrate catecholamines.
RESUMO
Preconcentration of catecholamines by the modified monolithic silica in the capillary was investigated in this study. In order to achieve a microchip-based method for determining catecholamines in the saliva, the monolithic silica was fabricated in the capillary and the monolithic silica was chemically modified by on-column reaction with phenylboronate. Different modified methods were compared. The concentration conditions were optimized. This study indicates the applicability of the modified monolithic silica capillary when it was used to concentrate catecholamines.