A new method for simultaneous determination of four phthalate esters （ PAEs） in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas...A new method for simultaneous determination of four phthalate esters （ PAEs） in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas chromatography-flame ionization detector （ GC-FID ）. Conditions for obtaining optimum extraction efficiency such as extraction solvents, morphologies of adsorbent, ion strength and pH were investigated and optimized in detail. Under the optimized conditions, the limits of detection （LODs） found for dibutyl phthalate （DBP） , butyl benzyl phthalate （BBP）, diethyl hexyl phthalate （DEHP） and di-n-octyl phthalate （DNOP） were 50, 25, 50 and 25 ng/g, respectively. Good linearity of four PAEs was achieved in the range of 50 to 4 000 ng/g. The proposed method was applied for analyzing different kinds of fat-containing samples. PAEs in commercial fat-containing samples can be highly extracted by a packed solid-phase extraction column of 5 mg polystyrene （ PS） nanofibers. The satisfactory average recoveries were obtained in the range of 96. 7% to 102. 3% , and the relative standard deviations （RSDs） below 5% were achieved. The proposed method reduces the organic solvent consumption, the complex and tedious procedures for sample pretreatment, and achieves high sensitivity and reproducibility for the investigated PAEs.展开更多
Hepatic stellate cells（HSCs） are a kind of fat-storing cells, the lipid droplets are rich in the Cytoplasm, in which retinyl ester accounts for 42%, triglyceride occupies 28%, cholesterol （total） occupies 13%, pho...Hepatic stellate cells（HSCs） are a kind of fat-storing cells, the lipid droplets are rich in the Cytoplasm, in which retinyl ester accounts for 42%, triglyceride occupies 28%, cholesterol （total） occupies 13%, phospholipids occupies 4% respectively. Studies have continued that thetransforms of HSC phenotype follows the changing of the cell lipid. After the activation of HSC, with HSC phenotype changing from fat-storing cells into myofibroblast, the lipid droplets decreased or disappeared gradually, which means HSCs are under the differentiating process of removing adipose, meawhile triglyceride, and the main content of lipid droplets, also obviously reduced. It was ever declined that during the process of HSC re-fating, the activated HSC would turn into quiescent state. Therefore this shows HSCs fat metabolism is closely related to the biological activity.展开更多
基金The National Basic Research Program of China(973Program)(No.2012CB933302)the National Instrumental Research Program(No.2014YQ06077303)+1 种基金the National Natural Science Foundation of China(No.81172720,21307086)Suzhou Science and Technology Department Foundation(No.ZXG201441)
文摘A new method for simultaneous determination of four phthalate esters （ PAEs） in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas chromatography-flame ionization detector （ GC-FID ）. Conditions for obtaining optimum extraction efficiency such as extraction solvents, morphologies of adsorbent, ion strength and pH were investigated and optimized in detail. Under the optimized conditions, the limits of detection （LODs） found for dibutyl phthalate （DBP） , butyl benzyl phthalate （BBP）, diethyl hexyl phthalate （DEHP） and di-n-octyl phthalate （DNOP） were 50, 25, 50 and 25 ng/g, respectively. Good linearity of four PAEs was achieved in the range of 50 to 4 000 ng/g. The proposed method was applied for analyzing different kinds of fat-containing samples. PAEs in commercial fat-containing samples can be highly extracted by a packed solid-phase extraction column of 5 mg polystyrene （ PS） nanofibers. The satisfactory average recoveries were obtained in the range of 96. 7% to 102. 3% , and the relative standard deviations （RSDs） below 5% were achieved. The proposed method reduces the organic solvent consumption, the complex and tedious procedures for sample pretreatment, and achieves high sensitivity and reproducibility for the investigated PAEs.
文摘Hepatic stellate cells（HSCs） are a kind of fat-storing cells, the lipid droplets are rich in the Cytoplasm, in which retinyl ester accounts for 42%, triglyceride occupies 28%, cholesterol （total） occupies 13%, phospholipids occupies 4% respectively. Studies have continued that thetransforms of HSC phenotype follows the changing of the cell lipid. After the activation of HSC, with HSC phenotype changing from fat-storing cells into myofibroblast, the lipid droplets decreased or disappeared gradually, which means HSCs are under the differentiating process of removing adipose, meawhile triglyceride, and the main content of lipid droplets, also obviously reduced. It was ever declined that during the process of HSC re-fating, the activated HSC would turn into quiescent state. Therefore this shows HSCs fat metabolism is closely related to the biological activity.
