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Fantao Meng - One of the best experts on this subject based on the ideXlab platform.
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preparation of uniform sized pla microcapsules by combining shirasu porous glass membrane emulsification technique and Multiple Emulsion solvent evaporation method
Journal of Controlled Release, 2005Co-Authors: Rong Liu, Fantao MengAbstract:Relatively Uniform-sized biodegradable poly(lactide) (PLA) microcapsules were successfully prepared by combining a Shirasu Porous Glass (SPG) membrane emulsification technique and Multiple Emulsion-solvent evaporation method. An aqueous phase containing lysozyme was used as the internal water phase (w1), and PLA and Arlacel 83 were dissolved in a mixture solvent of dichloromethane (DCM) and toluene which was used as the oil phase (o). These two solutions were emulsified by a homogenizer to form a w1/o primary Emulsion. The primary Emulsion was permeated through the uniform pores (5.25 microm) of an SPG membrane into the external water phase by the pressure of nitrogen gas to form the uniform w1/o/w2 droplets. Then, the solid polymer microcapsules were obtained by simply evaporating the solvent. It is necessary to avoid the phase separation of primary Emulsion during the SPG membrane emulsification. It was found that when the density difference of the internal water phase and oil phase was reduced to nearly zero and Arlacel 83 was used as the oil emulsifier, the phase separation was not observed within 24 h. The w1/o/w2 Emulsion with uniform diameter was obtained only when Arlaecl 83 concentration was limited below 2.5 wt.% based on oil phase. The drug encapsulation efficiency was found to be related to several factors including PLA molecular weight, additive type and its concentration in the internal water phase, the emulsifier type and concentration in the oil phase, the NaCl concentration and the pH value in the external water phase. Comparing with the stirring method, it was found that the size was more uniform and the drug encapsulation efficiency was much higher when the microcapsules were prepared by SPG membrane emulsification technique and the highest drug encapsulation efficiency of 92.20% was obtained. This is the first study to prepare PLA microcapsules by combining an SPG membrane emulsification technique and Multiple Emulsion-solvent evaporation method.
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preparation of uniform sized pla microcapsules by combining shirasu porous glass membrane emulsification technique and Multiple Emulsion solvent evaporation method
Journal of Controlled Release, 2005Co-Authors: Rong Liu, Fantao MengAbstract:Relatively Uniform-sized biodegradable poly(lactide) (PLA) microcapsules were successfully prepared by combining a Shirasu Porous Glass (SPG) membrane emulsification technique and Multiple Emulsion-solvent evaporation method. An aqueous phase containing lysozyme was used as the internal water phase (w(1)), and PLA and Arlacel 83 were dissolved in a mixture solvent of dichloromethane (DCM) and toluene which was used as the oil phase (o). These two solutions were emulsified by a homogenizer to form a w(1)/o primary Emulsion. The primary Emulsion was permeated through the uniform pores (5.25 mu m) of an SPG membrane into the external water phase by the pressure of nitrogen gas to form the uniform w(1)/o/w(2) droplets. Then, the solid polymer microcapsules were obtained by simply evaporating the solvent. It is necessary to avoid the phase separation of primary Emulsion during the SPG membrane emulsification. It was found that when the density difference of the internal water phase and oil phase was reduced to nearly zero and Arlacel 83 was used as the oil emulsifier, the phase separation was not observed within 24 h. The w(1)/o/w(2) Emulsion with uniform diameter was obtained only when Arlaecl 83 concentration was limited below 2.5 wt.% based on oil phase. The drug encapsulation efficiency was found to be related to several factors including PLA molecular weight, additive type and its concentration in the internal water phase, the emulsifier type and concentration in the oil phase, the NaCl concentration and the pH value in the external water phase. Comparing with the stirring method, it was found that the size was more uniform and the drug encapsulation efficiency was much higher when the microcapsules were prepared by SPG membrane emulsification technique and the highest drug encapsulation efficiency of 92.20% was obtained. This is the first study to prepare PLA microcapsules by combining an SPG membrane emulsification technique and Multiple Emulsion-solvent evaporation method. (c) 2004 Elsevier B.V. All rights reserved.
Rong Liu - One of the best experts on this subject based on the ideXlab platform.
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preparation of uniform sized pla microcapsules by combining shirasu porous glass membrane emulsification technique and Multiple Emulsion solvent evaporation method
Journal of Controlled Release, 2005Co-Authors: Rong Liu, Fantao MengAbstract:Relatively Uniform-sized biodegradable poly(lactide) (PLA) microcapsules were successfully prepared by combining a Shirasu Porous Glass (SPG) membrane emulsification technique and Multiple Emulsion-solvent evaporation method. An aqueous phase containing lysozyme was used as the internal water phase (w1), and PLA and Arlacel 83 were dissolved in a mixture solvent of dichloromethane (DCM) and toluene which was used as the oil phase (o). These two solutions were emulsified by a homogenizer to form a w1/o primary Emulsion. The primary Emulsion was permeated through the uniform pores (5.25 microm) of an SPG membrane into the external water phase by the pressure of nitrogen gas to form the uniform w1/o/w2 droplets. Then, the solid polymer microcapsules were obtained by simply evaporating the solvent. It is necessary to avoid the phase separation of primary Emulsion during the SPG membrane emulsification. It was found that when the density difference of the internal water phase and oil phase was reduced to nearly zero and Arlacel 83 was used as the oil emulsifier, the phase separation was not observed within 24 h. The w1/o/w2 Emulsion with uniform diameter was obtained only when Arlaecl 83 concentration was limited below 2.5 wt.% based on oil phase. The drug encapsulation efficiency was found to be related to several factors including PLA molecular weight, additive type and its concentration in the internal water phase, the emulsifier type and concentration in the oil phase, the NaCl concentration and the pH value in the external water phase. Comparing with the stirring method, it was found that the size was more uniform and the drug encapsulation efficiency was much higher when the microcapsules were prepared by SPG membrane emulsification technique and the highest drug encapsulation efficiency of 92.20% was obtained. This is the first study to prepare PLA microcapsules by combining an SPG membrane emulsification technique and Multiple Emulsion-solvent evaporation method.
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preparation of uniform sized pla microcapsules by combining shirasu porous glass membrane emulsification technique and Multiple Emulsion solvent evaporation method
Journal of Controlled Release, 2005Co-Authors: Rong Liu, Fantao MengAbstract:Relatively Uniform-sized biodegradable poly(lactide) (PLA) microcapsules were successfully prepared by combining a Shirasu Porous Glass (SPG) membrane emulsification technique and Multiple Emulsion-solvent evaporation method. An aqueous phase containing lysozyme was used as the internal water phase (w(1)), and PLA and Arlacel 83 were dissolved in a mixture solvent of dichloromethane (DCM) and toluene which was used as the oil phase (o). These two solutions were emulsified by a homogenizer to form a w(1)/o primary Emulsion. The primary Emulsion was permeated through the uniform pores (5.25 mu m) of an SPG membrane into the external water phase by the pressure of nitrogen gas to form the uniform w(1)/o/w(2) droplets. Then, the solid polymer microcapsules were obtained by simply evaporating the solvent. It is necessary to avoid the phase separation of primary Emulsion during the SPG membrane emulsification. It was found that when the density difference of the internal water phase and oil phase was reduced to nearly zero and Arlacel 83 was used as the oil emulsifier, the phase separation was not observed within 24 h. The w(1)/o/w(2) Emulsion with uniform diameter was obtained only when Arlaecl 83 concentration was limited below 2.5 wt.% based on oil phase. The drug encapsulation efficiency was found to be related to several factors including PLA molecular weight, additive type and its concentration in the internal water phase, the emulsifier type and concentration in the oil phase, the NaCl concentration and the pH value in the external water phase. Comparing with the stirring method, it was found that the size was more uniform and the drug encapsulation efficiency was much higher when the microcapsules were prepared by SPG membrane emulsification technique and the highest drug encapsulation efficiency of 92.20% was obtained. This is the first study to prepare PLA microcapsules by combining an SPG membrane emulsification technique and Multiple Emulsion-solvent evaporation method. (c) 2004 Elsevier B.V. All rights reserved.
James W Mcginity - One of the best experts on this subject based on the ideXlab platform.
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influence of processing on the stability and release properties of biodegradable microspheres containing thioridazine hydrochloride
European Journal of Pharmaceutics and Biopharmaceutics, 1998Co-Authors: Patrick B Odonnell, James W McginityAbstract:Abstract Biodegradable microspheres of poly( dl -lactic-co-glycolic acid) (PLGA) containing thioridazine HCl were produced by four Emulsion–solvent evaporation methods including an O/W Emulsion method, an O/O Emulsion method, a W/O/W Multiple Emulsion method, and a W/O/ O /O Multiple Emulsion method. Gel permeation chromatography was used to determine the molecular weight of the polymer before and after processing. Resultant microspheres were either incubated in an oven at 40°C, or stored in a desiccated chamber at 20°C. Change in the molecular weight of the polymer was monitored as a function of time. Premature degradation of the polymer was evident in microspheres produced by the O/W conventional solvent evaporation method. Thioridazine HCl catalyzed hydrolysis of PLGA was evident in normalized molecular weight distribution plots of the O/W microspheres. The in vitro release of thioridazine HCl from multiphase microspheres produced by potentiometric dispersion was compared with the release of drug from conventional microspheres prepared from the same polymer. Release of thioridazine HCl from multiphase microspheres of the W/O/ O /O type occurred by diffusion during initial stages of drug release.
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preparation of microspheres by the solvent evaporation technique
Advanced Drug Delivery Reviews, 1997Co-Authors: Patrick B Odonnell, James W McginityAbstract:Abstract The microencapsulation process in which the removal of the hydrophobic polymer solvent is achieved by evaporation has been widely reported in recent years for the preparation of microspheres and microcapsules based on biodegradable polymers and copolymers of hydroxy acids. The properties of biodegradable microspheres of poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA) have been extensively investigated. The encapsulation of highly water soluble compounds including proteins and peptides presents formidable challenges to the researcher. The successful encapsulation of such entities requires high drug loading in the microspheres, prevention of protein degradation by the encapsulation method, and predictable release of the drug compound from the microspheres. To achieve these goals, Multiple Emulsion techniques and other innovative modifications have been made to the conventional solvent evaporation process.
Shiow H Khew - One of the best experts on this subject based on the ideXlab platform.
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encapsulation of flavonoid in Multiple Emulsion using spinning disc reactor technology
Food Hydrocolloids, 2014Co-Authors: Mahmood Akhtar, Brent S. Murray, Ehihumeme I Afeisume, Shiow H KhewAbstract:Abstract Rutin (quercetin-3-rutinoside) and anthocyanin flavonoids have numerous biological activities which are beneficial to human health such as antioxidant and anti-inflammatory effects. In order to aid delivery of their health benefits, an attempt has been made to encapsulate rutin and Hibiscus anthocyanins in Multiple Emulsions using a spinning disc reactor (SDR) as a novel processing aid. The encapsulation of flavonoids may prolong their shelf-life and increase their bioavailability for absorption by the body ( Munin & Edwards-Levy, 2011 ). The advantage of using SDR technology in the second stage of emulsification is that it does not break the droplets of the primary Emulsion. The time-dependent stability of the Multiple Emulsions was investigated using particle size, microscopy, visual assessment and stability index measurements. At 2 wt.% emulsifier, Brij 78 was found to be capable of producing uniform droplets of the final W/O/W Emulsion in the size range of 13–15 μm. The results show that the SDR technology can be used as an alternative process for making stable W/O/W Multiple Emulsions with a fairly narrow droplet size distribution. Rutin and anthocyanins were successfully encapsulated within the internal aqueous phase of W/O/W Multiple Emulsions, giving an encapsulation efficiency of >80%. In the presence of flavonoids, a reduction in the average particle size has also been observed, possibly due to its surface active properties. Confocal laser microscopy confirmed the successful formation of SDR-processed Multiple Emulsions.
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Encapsulation of flavonoid in Multiple Emulsion using spinning disc reactor technology
Food Hydrocolloids, 2013Co-Authors: Mahmood Akhtar, Brent S. Murray, Ehihumeme I Afeisume, Shiow H KhewAbstract:Abstract Rutin (quercetin-3-rutinoside) and anthocyanin flavonoids have numerous biological activities which are beneficial to human health such as antioxidant and anti-inflammatory effects. In order to aid delivery of their health benefits, an attempt has been made to encapsulate rutin and Hibiscus anthocyanins in Multiple Emulsions using a spinning disc reactor (SDR) as a novel processing aid. The encapsulation of flavonoids may prolong their shelf-life and increase their bioavailability for absorption by the body ( Munin & Edwards-Levy, 2011 ). The advantage of using SDR technology in the second stage of emulsification is that it does not break the droplets of the primary Emulsion. The time-dependent stability of the Multiple Emulsions was investigated using particle size, microscopy, visual assessment and stability index measurements. At 2 wt.% emulsifier, Brij 78 was found to be capable of producing uniform droplets of the final W/O/W Emulsion in the size range of 13–15 μm. The results show that the SDR technology can be used as an alternative process for making stable W/O/W Multiple Emulsions with a fairly narrow droplet size distribution. Rutin and anthocyanins were successfully encapsulated within the internal aqueous phase of W/O/W Multiple Emulsions, giving an encapsulation efficiency of >80%. In the presence of flavonoids, a reduction in the average particle size has also been observed, possibly due to its surface active properties. Confocal laser microscopy confirmed the successful formation of SDR-processed Multiple Emulsions.
Elham Assadpour - One of the best experts on this subject based on the ideXlab platform.
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preparation of a Multiple Emulsion based on pectin whey protein complex for encapsulation of saffron extract nanodroplets
Food Chemistry, 2017Co-Authors: Afshin Faridi Esfanjani, Seid Mahdi Jafari, Elham AssadpourAbstract:The present study illustrates a simple and practical way to produce an adequate delivery system of bioactive compounds of saffron by protein-polysaccharide complex. Frist, crocin, safranal, and picrocrocin were loaded in nanodroplets (<100nm) by using water in oil (W/O) microEmulsions contain 5, and 10% aqueous saffron extract as a dispersed phase. These microEmulsions were then covered with whey protein concentrate (WPC)-maltodextrin or WPC-pectin-maltodextrin through water in oil in water (W/O/W) Multiple Emulsions. The stability and release of loaded crocin, safranal, and picrocrocin in Multiple Emulsions were investigated during 22days storage. The produced Multiple Emulsion by WPC-pectin-maltodextrin along with 5% inner aqueous phase showed a high stability and low release of encapsulated compounds over time. This Emulsion also provided a high protection of crocin, safranal, and picrocrocin in the gastric condition.
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Preparation of a Multiple Emulsion based on pectin-whey protein complex for encapsulation of saffron extract nanodroplets.
Food Chemistry, 2016Co-Authors: Afshin Faridi Esfanjani, Seid Mahdi Jafari, Elham AssadpourAbstract:Abstract The present study illustrates a simple and practical way to produce an adequate delivery system of bioactive compounds of saffron by protein-polysaccharide complex. Frist, crocin, safranal, and picrocrocin were loaded in nanodroplets (