The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Peter C Seville - One of the best experts on this subject based on the ideXlab platform.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5microm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release. (c)2007 Elsevier B.V. All rights reserved.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5 μm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release.
Tristan P Learoyd - One of the best experts on this subject based on the ideXlab platform.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5microm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release. (c)2007 Elsevier B.V. All rights reserved.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5 μm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release.
Eddie French - One of the best experts on this subject based on the ideXlab platform.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5microm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release. (c)2007 Elsevier B.V. All rights reserved.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5 μm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release.
Jane L Burrows - One of the best experts on this subject based on the ideXlab platform.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5microm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release. (c)2007 Elsevier B.V. All rights reserved.
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chitosan based spray dried respirable powders for sustained delivery of Terbutaline Sulfate
European Journal of Pharmaceutics and Biopharmaceutics, 2008Co-Authors: Tristan P Learoyd, Jane L Burrows, Eddie French, Peter C SevilleAbstract:In this study, we describe the preparation of highly dispersible dry powders for pulmonary drug delivery that display sustained drug release characteristics. Powders were prepared by spray-drying 30% v/v aqueous ethanol formulations containing Terbutaline Sulfate as a model drug, chitosan as a drug release modifier and leucine as an aerosolisation enhancer. The influence of chitosan molecular weight on the drug release profile was investigated by using low, medium and high molecular weight chitosan or combinations thereof. Following spray-drying, resultant powders were characterised using scanning electron microscopy, laser diffraction, tapped density analysis, differential scanning calorimetry and thermogravitational analysis. The in vitro aerosolisation performance and drug release profile were investigated using Multi-Stage Liquid Impinger analysis and modified USP II dissolution apparatus, respectively. The powders generated were of a suitable aerodynamic size for inhalation, had low moisture content and were amorphous in nature. The powders were highly dispersible, with emitted doses of over 90% and fine particle fractions of up to 82% of the total loaded dose, and mass median aerodynamic diameters of less than 2.5 μm. A sustained drug release profile was observed during dissolution testing; increasing the molecular weight of the chitosan in the formulation increased the duration of drug release.
Zhujun Zhang - One of the best experts on this subject based on the ideXlab platform.
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sensitive flow injection chemiluminescence determination of Terbutaline Sulfate based on enhancement of the luminol permanganate reaction
Analytical and Bioanalytical Chemistry, 2004Co-Authors: Zhouping Wang, Zhujun Zhang, Xiao ZhangAbstract:A novel and highly sensitive chemiluminescence (CL) method for the determination of Terbutaline Sulfate, coupled with flow-injection analysis (FIA), is described in this paper. The method is based on enhancement by Terbutaline Sulfate of the chemiluminescence emission of the luminol–permanganate system under alkaline conditions. Under the conditions selected the concentration of Terbutaline Sulfate is proportional to CL intensity in the range 5×10−10–5×10−7 g mL−1, with a detection limit of 1.7×10−10 g mL−1 (3σ). The relative standard deviation is 2.8% for 1×10−8 g mL−1 Terbutaline Sulfate (n=11). Ninety samples can be determined per hour. The proposed method has been used to determine Terbutaline Sulfate in pharmaceutical preparations and in plasma and urine samples with satisfactory results. The possible mechanism of the chemiluminescence reaction is discussed briefly.
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flow injection chemiluminescence detection for studying protein binding of Terbutaline Sulfate with on line microdialysis sampling
Journal of Pharmaceutical and Biomedical Analysis, 2003Co-Authors: Zhouping Wang, Zhujun Zhang, Dinglong Chen, Xiao ZhangAbstract:The binding of Terbutaline Sulfate to bovine serum albumin was studied in vitro using the technique of microdialysis sampling combined with flow-injection chemiluminescence analysis (FIA-CL). In the presence of formaldehyde, Terbutaline Sulfate can be oxidized by KMnO(4) to produce high chemiluminescence emission in Sulfate acid media. The concentration of Terbutaline Sulfate is proportional with the CL intensity in the range of 1 x 10(-7)-2 x 10(-5) mol l(-1) with a detection limit of 3 x 10(-8) mol l(-1). The drug and protein were mixed in different molar ratios in 0.067 mol l(-1) phosphate buffer, pH 7.4, and incubated at 37 degrees C in a water bath. The microdialysis probe was utilized to sample the mixed solution at a perfusion rate of 5 microl min(-1) and the dialytic efficiency of Terbutaline Sulfate under the experimental conditions was 26.3%. The data obtained by proposed microdialysis flow-injection chemiluminescence method was analyzed with Scrathard analysis and Klotz plot. The estimated association constant (K) and the number of the binding site (n) on one molecule of BSA by Scrathard analysis were 4.11 x 10(4) l mol(-1) and 1.06, respectively. The proposed system proved that FIA-CL coupled with on-line microdialysis sampling is a simple and reliable technique for the study of drug-protein interaction.
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a novel chemiluminescence method for determination of Terbutaline Sulfate based on potassium ferricyanide oxidation sensitized by rhodamine 6g
Journal of Pharmaceutical and Biomedical Analysis, 2003Co-Authors: Zhujun ZhangAbstract:This work reports a novel flow injection-chemiluminescence (FI-CL) system for determination of Terbutaline Sulfate, a drug for treatment of asthma and chronic obstructive pulmonary disease (COPD). It is based on the reaction of potassium ferricyanide with Terbutaline Sulfate in sodium hydroxide medium sensitized by the fluorescent dye rhodamine 6G. With the peak height as a quantitative parameter applying optimum working conditions, Terbutaline Sulfate is determined over the range of 0.01-1.2 microg ml(-1) with a detection limit of 6.7 x 10(-3) microg ml(-1). The relative standard deviation (R.S.D.) is 3.7% for 0.1 microg ml(-1) Terbutaline Sulfate (n = 11). The proposed method is sensitive, simple, rapid, and was applied to determination of Terbutaline Sulfate in pharmaceutical preparations. The possible chemiluminescence (CL) reaction mechanism was also discussed briefly.