The Experts below are selected from a list of 1602 Experts worldwide ranked by ideXlab platform
Tzufeng Tsai - One of the best experts on this subject based on the ideXlab platform.
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simultaneous analysis of antioxidants and preservatives in cosmetics by supercritical fluid extraction combined with liquid chromatography mass spectrometry
Journal of Chromatography A, 2006Co-Authors: Zuguang Li, Tzufeng TsaiAbstract:Abstract This study evaluated supercritical fluid extraction (SFE) combined with liquid chromatography–mass spectrometry (LC–MS) to determine trace preservatives and antioxidants including Methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BP), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol (α-t) and α-tocopherol acetate (α-ta) in cosmetic products. A supercritical fluid extraction procedure was used to isolate four paraben preservatives and four antioxidants from the cosmetic matrix before quantitative analysis. The optimum extraction condition was performed with static extraction for 5 min, then dynamic extraction for 20 min by using carbon dioxide supercritical fluid at 14,000 kPa and 65 °C. Methanol was used as collection solvent and the sea sand was chosen as a filling material. The analytes were separated on a C18 reversed-phase column using methanol–water as mobile phase and quantified by measuring its mass spectrometry. The linearity range is from 10 to 20,000 ng/g with RSD values below 18%. Detection limits are achieved at the level of 4.7–142 ng/g. It was successfully applied to the determination of paraben preservatives and antioxidants in cosmetics without tedious pretreatment.
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simultaneous analysis of antioxidants and preservatives in cosmetics by supercritical fluid extraction combined with liquid chromatography mass spectrometry
Journal of Chromatography A, 2006Co-Authors: Mawrong Lee, Chuehyu Lin, Tzufeng TsaiAbstract:This study evaluated supercritical fluid extraction (SFE) combined with liquid chromatography-mass spectrometry (LC-MS) to determine trace preservatives and antioxidants including Methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BP), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol (alpha-t) and alpha-tocopherol acetate (alpha-ta) in cosmetic products. A supercritical fluid extraction procedure was used to isolate four paraben preservatives and four antioxidants from the cosmetic matrix before quantitative analysis. The optimum extraction condition was performed with static extraction for 5 min, then dynamic extraction for 20 min by using carbon dioxide supercritical fluid at 14,000 kPa and 65 degrees C. Methanol was used as collection solvent and the sea sand was chosen as a filling material. The analytes were separated on a C18 reversed-phase column using methanol-water as mobile phase and quantified by measuring its mass spectrometry. The linearity range is from 10 to 20,000 ng/g with RSD values below 18%. Detection limits are achieved at the level of 4.7-142 ng/g. It was successfully applied to the determination of paraben preservatives and antioxidants in cosmetics without tedious pretreatment.
J P Dubost - One of the best experts on this subject based on the ideXlab platform.
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comparison of high performance liquid chromatography and capillary zone electrophoresis for the determination of parabens in a cosmetic product
Journal of Pharmaceutical and Biomedical Analysis, 2000Co-Authors: L Labat, E Kummer, P Dallet, J P DubostAbstract:Abstract A high-performance liquid chromatographic method (HPLC) and a capillary zone electrophoresis method (CZE) have been developed for the analysis of Methylparaben, ethylparaben, propylparaben and butylparaben in a commercial cosmetic product. A very simple extraction procedure with acidified diethylether was developed. The HPLC method involved a C18 reversed-phase column and a gradient of methanol and water-acetic acid (1%). Electrophoretic separation was performed on a fused-silica capillary with a mixed 15 mM tetraborate buffer (pH 9.2) and methanol (85:15, v/v). The calibration curves were linear from 1 to 40 μg/ml in HPLC and from 5 to 200 μg/ml in CZE. The limit of detection in CZE (0.21 μg/ml) was higher than in HPLC (0.05 μg/ml). Repeatability and intermediate precision were satisfactory for both methods (RSD values
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comparison of high performance liquid chromatography and capillary zone electrophoresis for the determination of parabens in a cosmetic product
Journal of Pharmaceutical and Biomedical Analysis, 2000Co-Authors: L Labat, E Kummer, P Dallet, J P DubostAbstract:A high-performance liquid chromatographic method (HPLC) and a capillary zone electrophoresis method (CZE) have been developed for the analysis of Methylparaben, ethylparaben, propylparaben and butylparaben in a commercial cosmetic product. A very simple extraction procedure with acidified diethylether was developed. The HPLC method involved a C18 reversed-phase column and a gradient of methanol and water-acetic acid (1%). Electrophoretic separation was performed on a fused-silica capillary with a mixed 15 mM tetraborate buffer (pH 9.2) and methanol (85:15, v/v). The calibration curves were linear from 1 to 40 microg/ml in HPLC and from 5 to 200 microg/ml in CZE. The limit of detection in CZE (0.21 microg/ml) was higher than in HPLC (0.05 microg/ml). Repeatability and intermediate precision were satisfactory for both methods (RSD values < 3.23% in HPLC and < 3.26%, in CZE). Only HPLC allowed the separation of butylparaben isomeric forms when CZE analysis was less time and reagents consuming. These results suggest that HPLC and CZE coupled with a simple extraction process are both suitable for parabens determination in cosmetic products.
Zuguang Li - One of the best experts on this subject based on the ideXlab platform.
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simultaneous analysis of antioxidants and preservatives in cosmetics by supercritical fluid extraction combined with liquid chromatography mass spectrometry
Journal of Chromatography A, 2006Co-Authors: Zuguang Li, Tzufeng TsaiAbstract:Abstract This study evaluated supercritical fluid extraction (SFE) combined with liquid chromatography–mass spectrometry (LC–MS) to determine trace preservatives and antioxidants including Methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BP), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol (α-t) and α-tocopherol acetate (α-ta) in cosmetic products. A supercritical fluid extraction procedure was used to isolate four paraben preservatives and four antioxidants from the cosmetic matrix before quantitative analysis. The optimum extraction condition was performed with static extraction for 5 min, then dynamic extraction for 20 min by using carbon dioxide supercritical fluid at 14,000 kPa and 65 °C. Methanol was used as collection solvent and the sea sand was chosen as a filling material. The analytes were separated on a C18 reversed-phase column using methanol–water as mobile phase and quantified by measuring its mass spectrometry. The linearity range is from 10 to 20,000 ng/g with RSD values below 18%. Detection limits are achieved at the level of 4.7–142 ng/g. It was successfully applied to the determination of paraben preservatives and antioxidants in cosmetics without tedious pretreatment.
Jian-liang Zhao - One of the best experts on this subject based on the ideXlab platform.
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determination of biocides in different environmental matrices by use of ultra high performance liquid chromatography tandem mass spectrometry
Analytical and Bioanalytical Chemistry, 2012Co-Authors: Zhi-feng Chen, Hao-chang Su, Fu-qiang Peng, Guang-guo Ying, Feng Chen, Jian-liang ZhaoAbstract:A sensitive and robust method using solid-phase extraction and ultrasonic extraction for preconcentration fol- lowed by ultra-high-performance liquid chromatography-tan- dem mass spectrometry (UHPLC-MS-MS) has been developed for determination of 19 biocides: eight azole fun- gicides (climbazole, clotrimazole, ketoconazole, miconazole, fluconazole, itraconazole, thiabendazole, and carbendazim), two insect repellents (N,N-diethyl-3-methylbenzamide (DEET), and icaridin (also known as picaridin)), three iso- thiazolinone antifouling agents (1,2-benzisothiazolinone (BIT), 2-n-octyl-4-isothiazolinone (OIT), and 4,5-dichloro-2- n-octyl-isothiazolinone (DCOIT)), four paraben preservatives (Methylparaben, ethylparaben, propylparaben, and butylpara- ben), and two disinfectants (triclosan and triclocarban) in surface water, wastewater, sediment, sludge, and soil. Recov- ery of the target compounds from surface water, influent, effluent, sediment, sludge, and soil was mostly in the range 70-120 %, with corresponding method quantification limits ranging from 0.01 to 0.31 ngL �1 , 0.07 to 7.48 ngL �1 ,0 .01 to
L Labat - One of the best experts on this subject based on the ideXlab platform.
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comparison of high performance liquid chromatography and capillary zone electrophoresis for the determination of parabens in a cosmetic product
Journal of Pharmaceutical and Biomedical Analysis, 2000Co-Authors: L Labat, E Kummer, P Dallet, J P DubostAbstract:Abstract A high-performance liquid chromatographic method (HPLC) and a capillary zone electrophoresis method (CZE) have been developed for the analysis of Methylparaben, ethylparaben, propylparaben and butylparaben in a commercial cosmetic product. A very simple extraction procedure with acidified diethylether was developed. The HPLC method involved a C18 reversed-phase column and a gradient of methanol and water-acetic acid (1%). Electrophoretic separation was performed on a fused-silica capillary with a mixed 15 mM tetraborate buffer (pH 9.2) and methanol (85:15, v/v). The calibration curves were linear from 1 to 40 μg/ml in HPLC and from 5 to 200 μg/ml in CZE. The limit of detection in CZE (0.21 μg/ml) was higher than in HPLC (0.05 μg/ml). Repeatability and intermediate precision were satisfactory for both methods (RSD values
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comparison of high performance liquid chromatography and capillary zone electrophoresis for the determination of parabens in a cosmetic product
Journal of Pharmaceutical and Biomedical Analysis, 2000Co-Authors: L Labat, E Kummer, P Dallet, J P DubostAbstract:A high-performance liquid chromatographic method (HPLC) and a capillary zone electrophoresis method (CZE) have been developed for the analysis of Methylparaben, ethylparaben, propylparaben and butylparaben in a commercial cosmetic product. A very simple extraction procedure with acidified diethylether was developed. The HPLC method involved a C18 reversed-phase column and a gradient of methanol and water-acetic acid (1%). Electrophoretic separation was performed on a fused-silica capillary with a mixed 15 mM tetraborate buffer (pH 9.2) and methanol (85:15, v/v). The calibration curves were linear from 1 to 40 microg/ml in HPLC and from 5 to 200 microg/ml in CZE. The limit of detection in CZE (0.21 microg/ml) was higher than in HPLC (0.05 microg/ml). Repeatability and intermediate precision were satisfactory for both methods (RSD values < 3.23% in HPLC and < 3.26%, in CZE). Only HPLC allowed the separation of butylparaben isomeric forms when CZE analysis was less time and reagents consuming. These results suggest that HPLC and CZE coupled with a simple extraction process are both suitable for parabens determination in cosmetic products.