To compare pharmacokinetic behaviors of nitrendipine submicron emulsion with nitrendipine solution following intravenous administration in rats.The plasma concentrations were analyzed by ultra-performance liquid chrom...To compare pharmacokinetic behaviors of nitrendipine submicron emulsion with nitrendipine solution following intravenous administration in rats.The plasma concentrations were analyzed by ultra-performance liquid chromatography coupled with tandem mass spectrometry detection(UPLC-MS/MS)through a new validated method.The pharmacokinetic parameters of the nitrendipine submicron emulsion and nitrendipine solution were as follows:AUC_(0-t) 900.76±186.59 versus 687.08±66.24 ng h/ml,C_(max) 854.54±159.48 versus 610.59±235.99 ng/ml,t_(1/2)2.37±1.99 versus 2.80±2.69 h.The relative bioavailability of nitrendipine submicron emulsion to nitrendipine solution was 131.4±11.3%.The developed methods could meet the requirements of bioanalysis.Compared to the solution injection,intravenous submicron emulsion presents higher systematic exposure which can help to improve the therapeutic efficacy.展开更多
Objective:The aim of this study was to discover the potential biomarkers changes on a rat model of isoproterenol (ISO) induced myocardial ischaemia before and after treatment with a Xiangdan submicron emulsion and to ...Objective:The aim of this study was to discover the potential biomarkers changes on a rat model of isoproterenol (ISO) induced myocardial ischaemia before and after treatment with a Xiangdan submicron emulsion and to explore the unclearing mechanisms by urinary metabolomics.Methods:Three active traditional Chinese medicine (TCM) ingredients were formulated into a lyophilized submicron emulsion powder with hydroxypropyl-β-cyclodextrin encapsulation by high pressure homogenization technology.The three ingredients were given both separately and combined,and the corresponding effects of the three drugs were compared.Principal component analysis (PCA) and the HPLC-UV analytical method was applied to explore the change of composition of urine metabolites in a rat model of isoproterenol induced myocardial ischaemia.Results:Analytical methods measuring the three active ingredients in urine samples were established.PCA score plots revealed that the therapeutic effect of the Xiangdan submicron emulsion was more significant than that of the Xiangdan injection.There was a synergistic effect among the three active ingredients.Furthermore,studies of rat metabolism changes and structure analysis of biological markers indicated that the mechanism of Xiangdan formulations was related to the inhibition of abnormal tryptophan metabolism.Conclusion:Xiangdan preparations had a confirmed effect in the treatment of coronary heart disease,especially with the novel Xiangdan submicron emulsion formulation.Urinary metabolomics methods to monitor special biomarker changes is an excellent method to reveal the mechanism of action of TCM drugs.展开更多
Submicron-sized peanut-shaped poly(methyl methacrylate)/polystyrene (PMMA/PS) particles were successfully synthesized by seeded soap-free emulsion polymerization of styrene on the spherical crosslinked PMMA seed p...Submicron-sized peanut-shaped poly(methyl methacrylate)/polystyrene (PMMA/PS) particles were successfully synthesized by seeded soap-free emulsion polymerization of styrene on the spherical crosslinked PMMA seed particles. The obtained peanut- shaped particles showed a novel internal morphology: PS phase formed one domain which linked to the other domain having PMMA core encased by PS shell.展开更多
文摘To compare pharmacokinetic behaviors of nitrendipine submicron emulsion with nitrendipine solution following intravenous administration in rats.The plasma concentrations were analyzed by ultra-performance liquid chromatography coupled with tandem mass spectrometry detection(UPLC-MS/MS)through a new validated method.The pharmacokinetic parameters of the nitrendipine submicron emulsion and nitrendipine solution were as follows:AUC_(0-t) 900.76±186.59 versus 687.08±66.24 ng h/ml,C_(max) 854.54±159.48 versus 610.59±235.99 ng/ml,t_(1/2)2.37±1.99 versus 2.80±2.69 h.The relative bioavailability of nitrendipine submicron emulsion to nitrendipine solution was 131.4±11.3%.The developed methods could meet the requirements of bioanalysis.Compared to the solution injection,intravenous submicron emulsion presents higher systematic exposure which can help to improve the therapeutic efficacy.
文摘Objective:The aim of this study was to discover the potential biomarkers changes on a rat model of isoproterenol (ISO) induced myocardial ischaemia before and after treatment with a Xiangdan submicron emulsion and to explore the unclearing mechanisms by urinary metabolomics.Methods:Three active traditional Chinese medicine (TCM) ingredients were formulated into a lyophilized submicron emulsion powder with hydroxypropyl-β-cyclodextrin encapsulation by high pressure homogenization technology.The three ingredients were given both separately and combined,and the corresponding effects of the three drugs were compared.Principal component analysis (PCA) and the HPLC-UV analytical method was applied to explore the change of composition of urine metabolites in a rat model of isoproterenol induced myocardial ischaemia.Results:Analytical methods measuring the three active ingredients in urine samples were established.PCA score plots revealed that the therapeutic effect of the Xiangdan submicron emulsion was more significant than that of the Xiangdan injection.There was a synergistic effect among the three active ingredients.Furthermore,studies of rat metabolism changes and structure analysis of biological markers indicated that the mechanism of Xiangdan formulations was related to the inhibition of abnormal tryptophan metabolism.Conclusion:Xiangdan preparations had a confirmed effect in the treatment of coronary heart disease,especially with the novel Xiangdan submicron emulsion formulation.Urinary metabolomics methods to monitor special biomarker changes is an excellent method to reveal the mechanism of action of TCM drugs.
基金supported by National Natural Science Foundation of China(No.50943028)Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Submicron-sized peanut-shaped poly(methyl methacrylate)/polystyrene (PMMA/PS) particles were successfully synthesized by seeded soap-free emulsion polymerization of styrene on the spherical crosslinked PMMA seed particles. The obtained peanut- shaped particles showed a novel internal morphology: PS phase formed one domain which linked to the other domain having PMMA core encased by PS shell.