A method using high performance liquid chromatography(HPLC)was developed for the s imultaneous determination of 13 preservatives(levulinic acid,p-hydroxyacetophenone,raspberry ketone,p-anisic acid,caprylhydroxamic aci...A method using high performance liquid chromatography(HPLC)was developed for the s imultaneous determination of 13 preservatives(levulinic acid,p-hydroxyacetophenone,raspberry ketone,p-anisic acid,caprylhydroxamic acid,hydroxyethoxyphenyl butanone,methylisothiazolinone,phenoxyethanol,b e n z oic acid,methylparaben,chlorphenesin,dehydroacetic acid,and 5-bromo-5-nitro-1,3-dioxane)in cosmetics.Different types of samples were ultrasonically extracted by methanol,then the separation of 13 preservatives was carried out on a column of Agilent ZORBAX Eclipse XDB-C18(250 mm×4.6 mm,5μm)by gradient elution at a flow rate of 1.0 mL/min,using 0.1%phosphoric acid solution and acetonitrile as mobile phases.The column temperature was 30℃,and the detection was completed by a diode array detector with the wavelengths at 275,230 and 210 nm.Suspected positive samples were further confirmed by liquid chromatography-tandem mass spectrometry or gas chromatography-mass spectrometry.The linear regression analysis data shows good linearity for 13 preservatives in the respective mass concentration range,with their correlation coefficients(r)greater than 0.9998.The limits of detection(LODs)and limits of quantitation(LOQs)of the method are in the ranges of 0.4-100.0 mg/kg and 1.2-250.0 mg/kg,respectively.At three spiked levels,the average recoveries for 13 target compounds in three kinds of matrix samples are within 84.0%-115.4%,and the relative standard deviations(RSD)are within 0.5%-4.8%(n=6).This method is convenient,efficient,and precise,which can be used for qualitative and quantitative analysis of common preservatives in daily cosmetics.展开更多
A method of high-performance liquid chromatography(HPLC)was established for simultaneous determination of 27 preservatives in toothpaste.Toothpaste samples were extracted with 50%aqueous methanol solution,ultrasonicat...A method of high-performance liquid chromatography(HPLC)was established for simultaneous determination of 27 preservatives in toothpaste.Toothpaste samples were extracted with 50%aqueous methanol solution,ultrasonicated and then filtered.The target compounds were separated on a C_(18) column(250 mm×4.6μm,5μm)with the mobile phase consisting of acetonitrile and aqueous phosphoric acid solution,the column temperature was 30℃,the sample volume was 10μL,the flow rate was 1 mL/min,and diode array detector was used.Under the optimal experimental conditions,good linear relationship was obtained and the correlation coefficient(R^(2))was greater than 0.9995.This method was accurate and sensitive,which was suitable for the qualitative and quantitative analysis of 27 preservatives in toothpaste.展开更多
Polyphenols were obtained from the natural dried Lonicerae flos by ultrasound-assisted extraction with ethanol as the solvent.Single factor experiment and response surface methodology were employed to optimize the ext...Polyphenols were obtained from the natural dried Lonicerae flos by ultrasound-assisted extraction with ethanol as the solvent.Single factor experiment and response surface methodology were employed to optimize the extraction conditions.Ultra-performance liquid chromatrography(UPLC)-tandem mass spectrometry(MS/MS)was employed to identify polyphenols based on the plant widely targeted metabolomics database in a qualitative and quantitative manner.The results showed that the optimal extraction conditions for total phenols from Lonicerae flos were ultrasound-assisted extraction with a solid-to-liquid ratio of 10∶1 g/mL and 57%ethanol at 70 W and 60°C for 11 min.The yield of total phenols extracted under the optimal conditions reached 71.08 mg/g.The phenols in Lonicerae flos were mainly chlorogenic acid isomers,and the flavonoids were mainly nobiletin,galuteolin,and homoarbutin.展开更多
文摘A method using high performance liquid chromatography(HPLC)was developed for the s imultaneous determination of 13 preservatives(levulinic acid,p-hydroxyacetophenone,raspberry ketone,p-anisic acid,caprylhydroxamic acid,hydroxyethoxyphenyl butanone,methylisothiazolinone,phenoxyethanol,b e n z oic acid,methylparaben,chlorphenesin,dehydroacetic acid,and 5-bromo-5-nitro-1,3-dioxane)in cosmetics.Different types of samples were ultrasonically extracted by methanol,then the separation of 13 preservatives was carried out on a column of Agilent ZORBAX Eclipse XDB-C18(250 mm×4.6 mm,5μm)by gradient elution at a flow rate of 1.0 mL/min,using 0.1%phosphoric acid solution and acetonitrile as mobile phases.The column temperature was 30℃,and the detection was completed by a diode array detector with the wavelengths at 275,230 and 210 nm.Suspected positive samples were further confirmed by liquid chromatography-tandem mass spectrometry or gas chromatography-mass spectrometry.The linear regression analysis data shows good linearity for 13 preservatives in the respective mass concentration range,with their correlation coefficients(r)greater than 0.9998.The limits of detection(LODs)and limits of quantitation(LOQs)of the method are in the ranges of 0.4-100.0 mg/kg and 1.2-250.0 mg/kg,respectively.At three spiked levels,the average recoveries for 13 target compounds in three kinds of matrix samples are within 84.0%-115.4%,and the relative standard deviations(RSD)are within 0.5%-4.8%(n=6).This method is convenient,efficient,and precise,which can be used for qualitative and quantitative analysis of common preservatives in daily cosmetics.
文摘A method of high-performance liquid chromatography(HPLC)was established for simultaneous determination of 27 preservatives in toothpaste.Toothpaste samples were extracted with 50%aqueous methanol solution,ultrasonicated and then filtered.The target compounds were separated on a C_(18) column(250 mm×4.6μm,5μm)with the mobile phase consisting of acetonitrile and aqueous phosphoric acid solution,the column temperature was 30℃,the sample volume was 10μL,the flow rate was 1 mL/min,and diode array detector was used.Under the optimal experimental conditions,good linear relationship was obtained and the correlation coefficient(R^(2))was greater than 0.9995.This method was accurate and sensitive,which was suitable for the qualitative and quantitative analysis of 27 preservatives in toothpaste.
基金Supported by Agricultural Science and Technology Innovation Fund Project of Hunan Province(2022CX87)Huaihua Municipal Institute of Science and Technology Cooperation Project(2022N1203)Science and Technology Talent Lifting Project of Hunan Province—Training Plan for Young and Middle-aged Scholars(2023TJ-Z01)。
文摘Polyphenols were obtained from the natural dried Lonicerae flos by ultrasound-assisted extraction with ethanol as the solvent.Single factor experiment and response surface methodology were employed to optimize the extraction conditions.Ultra-performance liquid chromatrography(UPLC)-tandem mass spectrometry(MS/MS)was employed to identify polyphenols based on the plant widely targeted metabolomics database in a qualitative and quantitative manner.The results showed that the optimal extraction conditions for total phenols from Lonicerae flos were ultrasound-assisted extraction with a solid-to-liquid ratio of 10∶1 g/mL and 57%ethanol at 70 W and 60°C for 11 min.The yield of total phenols extracted under the optimal conditions reached 71.08 mg/g.The phenols in Lonicerae flos were mainly chlorogenic acid isomers,and the flavonoids were mainly nobiletin,galuteolin,and homoarbutin.
