The Experts below are selected from a list of 2325 Experts worldwide ranked by ideXlab platform
Melgardt M De Villiers - One of the best experts on this subject based on the ideXlab platform.
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compounded laxative formulations for substituting phenolphthalein with sennosides a b in solid dosage forms
Tropical Journal of Pharmaceutical Research, 2007Co-Authors: Quintin Verloop, Andries F Marais, Wilna Liebenberg, Melgardt M De VilliersAbstract:Purpose: Following the discovery of the carcinogenicity of phenolphthalein and the subsequent ban of this compound in several countries this study was undertaken to develop compounded formulations of laxative products containing the stimulant laxatives sennosides A and B. Methods: DSC and HPLC analysis was used to determine the compatibility of sennosides with commonly used excipients before compounding capsules, Tablets and Effervescent Tablets containing sennosides A & B. The physical and chemical stability and release properties of these dosage forms were determined for 12 weeks at increased temperature and relative humidity. Results: Sennosides A & B were compatible with a wide variety of powdered excipients. However, these were incompatible with propyl paraben, sodium carbonate, stearic acid, citric acid, PEG, and sugar derivatives such as lactose, glucose and sorbitol when granulated with water. Not withstanding these interactions, it was possible to compound simple capsule, Tablet and even an Effervescent Tablet formulations containing sennosides A & B that complied with pharmacopeial specifications. However, all these formulations were sensitive to moisture because when stored at increased temperature and relative humidity, disintegration times increased and dissolution rates decreased. Conclusion: Based on compatibility and stability studies simple, stable and elegant solid dosage forms containing sennosides A & B were compounded that can be used to replace phenolphthalein in a variety of solid dosage forms.
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Compounded laxative formulations for substituting phenolphthalein with sennosides A & B in solid dosage forms
Tropical Journal of Pharmaceutical Research, 2007Co-Authors: Quintin Verloop, Andries F Marais, Wilna Liebenberg, Melgardt M De VilliersAbstract:Purpose: Following the discovery of the carcinogenicity of phenolphthalein and the subsequent ban of this compound in several countries this study was undertaken to develop compounded formulations of laxative products containing the stimulant laxatives sennosides A and B. Methods: DSC and HPLC analysis was used to determine the compatibility of sennosides with commonly used excipients before compounding capsules, Tablets and Effervescent Tablets containing sennosides A & B. The physical and chemical stability and release properties of these dosage forms were determined for 12 weeks at increased temperature and relative humidity. Results: Sennosides A & B were compatible with a wide variety of powdered excipients. However, these were incompatible with propyl paraben, sodium carbonate, stearic acid, citric acid, PEG, and sugar derivatives such as lactose, glucose and sorbitol when granulated with water. Not withstanding these interactions, it was possible to compound simple capsule, Tablet and even an Effervescent Tablet formulations containing sennosides A & B that complied with pharmacopeial specifications. However, all these formulations were sensitive to moisture because when stored at increased temperature and relative humidity, disintegration times increased and dissolution rates decreased. Conclusion: Based on compatibility and stability studies simple, stable and elegant solid dosage forms containing sennosides A & B were compounded that can be used to replace phenolphthalein in a variety of solid dosage forms.
Yanyan Li - One of the best experts on this subject based on the ideXlab platform.
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magnetic Effervescent Tablet assisted ionic liquid based dispersive liquid liquid microextraction of polybrominated diphenyl ethers in liquid matrix samples
Talanta, 2019Co-Authors: Yanyan Li, Jia Hu, Peipei Zhou, Yaxin Zhang, Bo Zhang, Randy A Dahlgren, Xuedong Wang, Yikai ZhouAbstract:Abstract Herein, a novel method, magnetic Effervescent Tablet-assisted ionic liquid-based dispersive liquid-liquid microextraction (META-IL-DLLME), was pioneered for extraction and preconcentration of polybrominated diphenyl ethers (PBDEs) in liquid matrix samples. In this proposed method, a magnetic Effervescent Tablet, containing CO2 sources, ionic liquids and Fe3S4 magnetic nanoparticles (MNPs), combines extractant dispersion and magnetic recovery into one-step. Fe3S4 was synthesized, characterized and applied it for the first time to the newly developed method, and its extraction recoveries (ERs) for PBDEs were 20.8–32.0% higher than those of conventional Fe3O4 MNPs. The increased ERs of Fe3S4 resulted from its larger specific surface area and pore size. Some important parameters were rigorously optimized, such as kinds of magnetic nanoparticles, Effervescent agents, extraction solvents and their volumes, elution solvents, extraction temperature and salt addition. Under the optimized conditions, the META-IL-DLLME method combined with HPLC-DAD analysis gave the linear ranges of 0.1–0.5–100 µg L−1 with correlation coefficients of > 0.9990. The ERs ranged from 80.7% to 99.3%, and the limits of detection and quantitation were 0.012–0.078 µg L−1 and 0.04–0.26 µg L−1, respectively. The intra- and inter-day precisions, expressed as relative standard deviations (RSD, n = 6), were 1.32–4.83% and 1.99–4.25%, respectively. To evaluate its matrix effect, the relative recoveries of PBDEs from tap and river water, skim and whole milk, pregnant women and women serum samples at three fortification levels (2.0, 5.0 and 20.0 µg L−1) were in the range of 77.3–106.7%. Overall, the commercial Fe3O4 MNPs can only be used for magnetic separation in microextraction procedures, while Fe3S4 MNPs gave the higher adsorption and extraction efficiency for organic analytes besides the convenient magnetic separation. Therefore, the results obtained in this study provide a superior alternative for the conventional magnetic separation and adsorbent material. Also, this newly developed method has a great potential in routine monitoring of liquid matrix samples.
Wenfeng Zhou - One of the best experts on this subject based on the ideXlab platform.
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use of magnetic Effervescent Tablet assisted ionic liquid dispersive liquid liquid microextraction to extract fungicides from environmental waters with the aid of experimental design methodology
Analytica Chimica Acta, 2016Co-Authors: Miyi Yang, Yuhan Jia, Xiaoling Yang, Sanbing Zhang, Haixiang Gao, Wenfeng ZhouAbstract:In this work, a novel effervescence-assisted microextraction technique was proposed for the detection of four fungicides. This method combines ionic liquid-based dispersive liquid-liquid microextraction with the magnetic retrieval of the extractant. A magnetic Effervescent Tablet composed of Fe3O4 magnetic nanoparticles, sodium carbonate, sodium dihydrogen phosphate and 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonimide) was used for extractant dispersion and retrieval. The main factors affecting the extraction efficiency were screened by a Plackett-Burman design and optimized by a central composite design. Under the optimum conditions, good linearity was obtained for all analytes in pure water model and real water samples. Just for the pure water, the recoveries were between 84.6% and 112.8%, the limits of detection were between 0.02 and 0.10 μg L(-1) and the intra-day precision and inter-day precision both are lower than 4.9%. This optimized method was successfully applied in the analysis of four fungicides (azoxystrobin, triazolone, cyprodinil, trifloxystrobin) in environmental water samples and the recoveries ranged between 70.7% and 105%. The procedure promising to be a time-saving, environmentally friendly, and efficient field sampling technique.
Yikai Zhou - One of the best experts on this subject based on the ideXlab platform.
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magnetic Effervescent Tablet assisted ionic liquid based dispersive liquid liquid microextraction of polybrominated diphenyl ethers in liquid matrix samples
Talanta, 2019Co-Authors: Yanyan Li, Jia Hu, Peipei Zhou, Yaxin Zhang, Bo Zhang, Randy A Dahlgren, Xuedong Wang, Yikai ZhouAbstract:Abstract Herein, a novel method, magnetic Effervescent Tablet-assisted ionic liquid-based dispersive liquid-liquid microextraction (META-IL-DLLME), was pioneered for extraction and preconcentration of polybrominated diphenyl ethers (PBDEs) in liquid matrix samples. In this proposed method, a magnetic Effervescent Tablet, containing CO2 sources, ionic liquids and Fe3S4 magnetic nanoparticles (MNPs), combines extractant dispersion and magnetic recovery into one-step. Fe3S4 was synthesized, characterized and applied it for the first time to the newly developed method, and its extraction recoveries (ERs) for PBDEs were 20.8–32.0% higher than those of conventional Fe3O4 MNPs. The increased ERs of Fe3S4 resulted from its larger specific surface area and pore size. Some important parameters were rigorously optimized, such as kinds of magnetic nanoparticles, Effervescent agents, extraction solvents and their volumes, elution solvents, extraction temperature and salt addition. Under the optimized conditions, the META-IL-DLLME method combined with HPLC-DAD analysis gave the linear ranges of 0.1–0.5–100 µg L−1 with correlation coefficients of > 0.9990. The ERs ranged from 80.7% to 99.3%, and the limits of detection and quantitation were 0.012–0.078 µg L−1 and 0.04–0.26 µg L−1, respectively. The intra- and inter-day precisions, expressed as relative standard deviations (RSD, n = 6), were 1.32–4.83% and 1.99–4.25%, respectively. To evaluate its matrix effect, the relative recoveries of PBDEs from tap and river water, skim and whole milk, pregnant women and women serum samples at three fortification levels (2.0, 5.0 and 20.0 µg L−1) were in the range of 77.3–106.7%. Overall, the commercial Fe3O4 MNPs can only be used for magnetic separation in microextraction procedures, while Fe3S4 MNPs gave the higher adsorption and extraction efficiency for organic analytes besides the convenient magnetic separation. Therefore, the results obtained in this study provide a superior alternative for the conventional magnetic separation and adsorbent material. Also, this newly developed method has a great potential in routine monitoring of liquid matrix samples.
Quintin Verloop - One of the best experts on this subject based on the ideXlab platform.
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compounded laxative formulations for substituting phenolphthalein with sennosides a b in solid dosage forms
Tropical Journal of Pharmaceutical Research, 2007Co-Authors: Quintin Verloop, Andries F Marais, Wilna Liebenberg, Melgardt M De VilliersAbstract:Purpose: Following the discovery of the carcinogenicity of phenolphthalein and the subsequent ban of this compound in several countries this study was undertaken to develop compounded formulations of laxative products containing the stimulant laxatives sennosides A and B. Methods: DSC and HPLC analysis was used to determine the compatibility of sennosides with commonly used excipients before compounding capsules, Tablets and Effervescent Tablets containing sennosides A & B. The physical and chemical stability and release properties of these dosage forms were determined for 12 weeks at increased temperature and relative humidity. Results: Sennosides A & B were compatible with a wide variety of powdered excipients. However, these were incompatible with propyl paraben, sodium carbonate, stearic acid, citric acid, PEG, and sugar derivatives such as lactose, glucose and sorbitol when granulated with water. Not withstanding these interactions, it was possible to compound simple capsule, Tablet and even an Effervescent Tablet formulations containing sennosides A & B that complied with pharmacopeial specifications. However, all these formulations were sensitive to moisture because when stored at increased temperature and relative humidity, disintegration times increased and dissolution rates decreased. Conclusion: Based on compatibility and stability studies simple, stable and elegant solid dosage forms containing sennosides A & B were compounded that can be used to replace phenolphthalein in a variety of solid dosage forms.
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Compounded laxative formulations for substituting phenolphthalein with sennosides A & B in solid dosage forms
Tropical Journal of Pharmaceutical Research, 2007Co-Authors: Quintin Verloop, Andries F Marais, Wilna Liebenberg, Melgardt M De VilliersAbstract:Purpose: Following the discovery of the carcinogenicity of phenolphthalein and the subsequent ban of this compound in several countries this study was undertaken to develop compounded formulations of laxative products containing the stimulant laxatives sennosides A and B. Methods: DSC and HPLC analysis was used to determine the compatibility of sennosides with commonly used excipients before compounding capsules, Tablets and Effervescent Tablets containing sennosides A & B. The physical and chemical stability and release properties of these dosage forms were determined for 12 weeks at increased temperature and relative humidity. Results: Sennosides A & B were compatible with a wide variety of powdered excipients. However, these were incompatible with propyl paraben, sodium carbonate, stearic acid, citric acid, PEG, and sugar derivatives such as lactose, glucose and sorbitol when granulated with water. Not withstanding these interactions, it was possible to compound simple capsule, Tablet and even an Effervescent Tablet formulations containing sennosides A & B that complied with pharmacopeial specifications. However, all these formulations were sensitive to moisture because when stored at increased temperature and relative humidity, disintegration times increased and dissolution rates decreased. Conclusion: Based on compatibility and stability studies simple, stable and elegant solid dosage forms containing sennosides A & B were compounded that can be used to replace phenolphthalein in a variety of solid dosage forms.
