Abstract：
:The objective of this study was to prepare floating theophylline microspheres with zero order release profiles for use as buoyant reservoirs with increased retention time in the stomach. The microspheres were prepared by a modified emulsion-solvent evaporation method using a polymer mixture of cellulose acetate butyrate and Eudragit RL 100 (1:1). The drug-polymer dispersions were pressurized under carbon dioxide gas which dissolved in the drug-polymer dispersions and formed bubbles upon the release of the pressure. Some of the bubbles were entrapped in the dispersed drug-polymer droplets and eventually formed internal cavities in the microspheres. The resulting microspheres were characterized for size distribution, morphology, density, drug-polymer content, buoyant capacity and drug release behaviour. The microspheres were spherical with relatively smooth surfaces with round hollow cavities. The microspheres and low densities (less than 1 g/cm3) and remained floating for more than 24 h in pH 1.2 and 7.5 buffers. The dissolution profiles of the floating theophylline microspheres showed near zero order kinetics and sustained release in both pH 1.2 and 7.5 buffers. Modified microspheres processed with the addition of 2% w/v polysorbate 80 to the internal phase had smaller sizes, lower densities and faster drug release compared with those without the addition of the surfactant.
journal_name
J Microencapsuljournal_title
Journal of microencapsulationauthors
Stithit S,Chen W,Price JCdoi
10.3109/02652049809008255subject
Has Abstractpub_date
1998-11-01 00:00:00pages
725-37issue
6eissn
0265-2048issn
1464-5246journal_volume
15pub_type
杂志文章abstract：:Drug release from gelatin/poly(acrylic acid) oxprenolol-loaded microspheres has been evaluated using an in situ sink immersion method and a wetting method. The kinetics of drug release were analysed by applying the empirical exponential equation and by the calculation of the approximate contribution of the diffusional...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652049709033835
更新日期：1997-07-01 00:00:00
abstract：:Abietic acid was isolated from rosin N Grade (ISI) by a simple process and the product was further standardized. Sulphadiazine microcapsules were prepared by the solvent evaporation technique, using abietic acid as a wall-forming material. Discrete, spherical and free-flowing microcapsules were obtained by phase separ...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652049209040481
更新日期：1992-10-01 00:00:00
abstract：CONTEXT:Quercetin (QUE) is a flavonoid with antioxidant/anti-inflammatory properties, poorly absorbed when orally administered. OBJECTIVES:To prepare chitosan/xanthan gum microparticles to increase QUE oral bioavailability and optimize its release in the colon. MATERIALS AND METHODS:Chitosan/xanthan gum hydrogel embe...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048.2014.913726
更新日期：2014-01-01 00:00:00
abstract：:Microencapsulation of ketoprofen using Eudragit RS and RL (acrylic resins) was investigated based on the dispersion system of ketoprofen-containing acetone in liquid paraffin. Aluminium tristearate was used as an additive for the preparation of microcapsules. Good reproducibility was observed in the microencapsulation...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048609021799
更新日期：1986-10-01 00:00:00
abstract：:The chitosan microspheres were prepared by a membrane emulsification method with variations of the N2 gas pressure and the chitosan concentration. The pressure of N2 gas was varied within the range from 0.2 x 10(5) to 0.8 x 10(5) Pa at chitosan concentration 1.5 wt%. In addition, the concentration of chitosan was vari...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652040410001729304
更新日期：2004-08-01 00:00:00
abstract：:Nanoencapsulation by spray drying was performed to protect and preserve antioxidant rich dietary polyphenols from green coffee beans. Nano-encapsulation of green coffee was done using maltodextrin as wall material. The nanoparticles were further characterised by zetasizer, differential scanning colorimetry, X-ray diff...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652048.2019.1692946
更新日期：2020-01-01 00:00:00
abstract：:In this study, ethylcellulose and acrylate-methacrylate copolymer (Eudragit RL 100, Eudragit RS 100) membranes were prepared by using appropriate types and amounts of plasticizers. Thirty percent and 20% of triacetin based on polymer weight were found to be appropriate plasticizers for ethylcellulose membranes and acr...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652049609026048
更新日期：1996-11-01 00:00:00
abstract：:The objective of this study was to prepare a microparticulate drug delivery system being based on a new thiomer, namely a chitosan 2-iminothiolane conjugate (chitosan-TBA conjugate). Due to thiol groups being immobilized on chitosan, chitosan-TBA conjugate exhibits improved mucoadhesive and permeation enhancing proper...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652040500162220
更新日期：2005-08-01 00:00:00
abstract：:Radioembolization is used in diagnostic imaging of the lungs and for radioembolization therapy of hepatic tumours. Presently, 99mTc labelled macroaggregates or microspheres of human serum albumin (HAM) are used for this purpose. Poly lactic acid (PLA) is biodegradable, like HAM, and, unlike HAM, is not a blood product...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/026520400405750
更新日期：2000-07-01 00:00:00
abstract：:Alginate bead containing calcium carbonate particle were prepared by dropping the suspension of alginate/calcium carbonate (4/1, w/w) into aqueous solution of CaCl(2) (0.1 M). The pH-dependent release property of the bead was observed for 12 h using blue dextran as a model drug. The release increased up to 4 h in a sa...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652040701657820
更新日期：2007-12-01 00:00:00
abstract：:Liposomes containing Isovist were prepared by controlled detergent dialysis as well as by reverse phase evaporation. After preparation these liposomes were lyophilized and then submitted to sterilization by ethylene oxide. Prior to lyophilization, trehalose was added as a protective agent to preserve the size of the l...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048909031168
更新日期：1989-10-01 00:00:00
abstract：:Freeze-drying is an effective way to improve long-term physical stability of nanosuspension in drug delivery applications. Nanosuspension also known as suspension of nanoparticles. In this study, the effect of freeze-drying with different cryoprotectants on the physicochemical characteristics of resveratrol (RSV) nano...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652048.2018.1462416
更新日期：2018-05-01 00:00:00
abstract：:The effect of process variables such as nozzle size, flow-rate of dispersed phase, inter-electrode distance, and presence of an acid acceptor and a thickening agent in the dispersed phase, on the production and size distribution of nylon 6-10 microcapsules prepared by interfacial polymerization in a high-voltage elect...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652049509015288
更新日期：1995-03-01 00:00:00
abstract：:This study demonstrates the feasibility of using a single-capillary electrospray (ES) system to generate novel alpha-lipoic acid encapsulated poly(ethylene oxide)-chitosan (ALA/PEO/CS) particles with a monodispersed diameter. Scanning electron microscopic images (SEM) and dynamic light scattering (DLS) results indicat...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048.2013.863395
更新日期：2014-01-01 00:00:00
abstract：:Indomethacin-loaded dietheylaminoethyl trisacryl microspheres (DEAE-MS), originally designed for therapeutic embolization, were encapsulated using two methods: coacervation and solvent evaporation/extraction. This encapsulation was achieved using a biocompatible polymer, the PLGA 50 : 50, and aimed to control the rele...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652040701843388
更新日期：2008-03-01 00:00:00
abstract：:Nanoparticles prepared of human serum albumin (HSA) represent promising carriers for drug delivery. Desolvating procedure is a common method to obtain protein-based particles. However process parameters have a great influence on size, size distribution and particle yield of the resulting formulation. Therefore, it is ...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048.2011.635218
更新日期：2012-01-01 00:00:00
abstract：:Optimum conditions for the preparation of non-magnetic and magnetic microspheres of albumin-globulin mix (alglomix) containing mefenamic acid have been standardized. The effect of various parameters has been investigated with regard to the appearance, yield, drug content and encapsulation efficiency. The physicochemic...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652049109021856
更新日期：1991-01-01 00:00:00
abstract：CONTEXT:Coated whey protein micro-beads may improve probiotic protection and provide delayed cell-release mechanisms. OBJECTIVE:Lactobacillus rhamnosus GG was encapsulated in whey protein micro-beads by droplet extrusion with coating via electrostatic deposition: primary-polysaccharide and secondary-whey protein. MAT...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048.2011.638994
更新日期：2012-01-01 00:00:00
abstract：:Polylactic acid microcapsules containing randomly distributed hydrocortisone particles were prepared. The rate of release of hydrocortisone from the microcapsules in pH 7.4 phosphate buffer was found to be largely increased by the presence of polysorbate 80, cetylpyridinium chloride, or aerosol OT in the dissolution m...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048809036721
更新日期：1988-01-01 00:00:00
abstract：:Immunomagnetic systems have been used for positive selection of a cell fraction from a mixture using appropriate surface markers with satisfactory results, as haematopoietic CD34+ cells. This work reports on the development of poly(ethylene glycol)-grafted (PEG) immunoliposomes loaded with citrate-magnetite stabilized...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/026520401750038593
更新日期：2001-01-01 00:00:00
abstract：AIMS:This study was aimed to develop Isotretinoin (ITN) and α-tocopherol acetate (α-TA) loaded solid lipid nanoparticle topical gel for better skin sensitivity and potentiation of efficacy. METHODS:ITN and α-TA-loaded solid lipid nanoparticles (AE-SLN) were prepared by microemulsion method with glyceryl mono-stearate ...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652048.2020.1823499
更新日期：2020-12-01 00:00:00
abstract：:The aim was to study the effect of the type of polymer solvent on characteristics of microspheres produced by spray drying. The water-soluble model protein, bovine serum albumin (BSA) was microencapsulated into biodegradable poly(D,L-lactic acid) using the following 10 different polymer solvents: acetaldehyde dimethyl...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652049509051129
更新日期：1995-01-01 00:00:00
abstract：:The aim of this study was to investigate how glass transition temperature (Tg) influenced polymer microsphere formation and degradation of three chemically, similar novel salicylatebased poly(anhydride-esters): poly[1,6-bis(o-carboxyphenoxy)hexanoate] (CPH), Tg = 59 degrees C; poly[1,8-bis(o-carboxyphenoxy)octanoate] ...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652040600776481
更新日期：2006-09-01 00:00:00
abstract：:The factors influencing the encapsulation of azathioprine (AZA) into liposomes were investigated to find out the conditions for its optimal entrapment. Similar studies for comparison were also carried out on 6-mercaptopurine (6-MP), of which AZA is a prodrug. AZA and also 6-MP show higher encapsulation efficiencies in...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652049809006875
更新日期：1998-07-01 00:00:00
abstract：:Biodegradable hollow capsules filled with fluorescently labelled bovine serum albumin (BSA) as a model drug were prepared via layer-by-layer (LbL) self-assembly of type-I collagen (COL) and hyaluronic acid (HA) using calcium carbonate micro-particles and co-precipitation method. Capsules loaded with fluorescein isothi...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048.2013.834995
更新日期：2014-01-01 00:00:00
abstract：:The blood-brain barrier (BBB) is the major problem for the treatment of central nervous system diseases. A previous study from our group showed that the brain-targeted chitosan nanoparticles-loaded with large peptide moieties can rapidly cross the barrier and provide neuroprotection. The present study aims to determin...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652048.2017.1375039
更新日期：2017-11-01 00:00:00
abstract：:D,L-polylactic acid (PLA) microspheres containing quinidine base and quinidine sulphate were prepared by the solvent evaporation method. The present study was carried out to examine how various process parameters in the aqueous phase influenced the preparation and properties of PLA-microspheres. The amount of drug tha...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652048709021821
更新日期：1987-10-01 00:00:00
abstract：:A combined approach based on drug cyclodextrin (CD) complexation and loading into PLGA nanoparticles (NP) has been developed to improve oxaprozin therapeutic efficiency. This strategy exploits the solubilizing and stabilizing properties of CDs and the prolonged-release and targeting properties of PLGA NPs. Drug-loaded...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.3109/02652040903515508
更新日期：2010-01-01 00:00:00
abstract：:A considerable effort has been spent in the past three decades to investigate various aspects of liposomes as novel drug delivery systems. In 1990, the first amphotericin B (AmB) liposomal preparation (L-AmB) under the brand name AmBisome was introduced into the market by Vestar. The successful marketing of the produc...
journal_title：Journal of microencapsulation
pub_type： 杂志文章,评审
doi：10.3109/02652049809006844
更新日期：1998-03-01 00:00:00
abstract：:The aim of this study was to formulate, characterise and evaluate the activity of amodiaquine microparticles against Leishmania donovani. Microparticles were formulated by encapsulating the drug in bovine serum albumin using the spray-dryer method. The microparticles were evaluated for size, zeta potential, drug conte...
journal_title：Journal of microencapsulation
pub_type： 杂志文章
doi：10.1080/02652048.2017.1280094
更新日期：2017-02-01 00:00:00
