A biodegradable modified guar gum microsphere was prepared for the first time by ionic gelation of the guar gum derivative containing quarternary ammonium group with tripolyphosphate at room temperature in the absence of emulsifying agent or organic solvent. Its average particle diameter was about 140 microm and the particle size had a narrow and normal gauss distribution. From the loading experiment of bovine serum album (BSA) with various concentrations, it was found that the encapsulation efficiency is more than 80%. By the investigation of in vitro release from the BSA-loaded microsphere, it was found that the BSA had a continuous release for more than 6 hours and the release percentage was affected by the initial concentration of the BSA and temperature.
Biocompatible Materials ; chemistry ; Drug Carriers ; chemistry ; Drug Delivery Systems ; Galactans ; chemistry ; Mannans ; chemistry ; Microspheres ; Plant Gums ; chemistry ; Proteins ; administration & dosage ; Serum Albumin, Bovine ; administration & dosage

This study evaluates the pathogenesis of rheumatoid arthritis by producing immune complex induced arthritis with an intra-articular injection of BSA in immunized rabbits, and the effect of systemic administration of cyclophosphamide and local administration of anti-macrophage serum. The reduction of inflammatory reaction by cyclophosphamide administration appears to be caused mainly by selective depletion of the neutrophils, and partly by immune suppression. It appears that the rabbit abdominal macrophage has the common morphologic, functional and antigenic patterns with the M-type synovial lining cells. There is another possibility that the cross-reacting antigens between macrophage and the M-type cell of the synovial lining may exist. It is concluded that in this experimental immune complex arthritis, the site of localization of immune complexes seems to be the synovial, M-type cell, and the tissue injury of synovium is largely mediated not only by neutrophils and complement, but also by macrophages.
Animal ; Antigen-Antibody Complex* ; Arthritis, Rheumatoid/etiology* ; Cyclophosphamide/pharmacology ; Immune Complex Diseases/etiology* ; Immune Sera/pharmacology ; Macrophages ; Rabbits ; Serum Albumin, Bovine/administration & dosage ; Synovial Membrane/pathology

AIMTo study the preparation of bovine serum albumin nanoparticles surface-modified with glycyrrhizin(BSA-NP-GL) targeting to hepatocytes.

METHODSThe bovine serum albumin nanoparticles (BSA-NP) were prepared by desolvation process. Glycyrrhizin (GL) was oxidized by sodium periodate to be conjugated to surface reactive amino groups (SRAG) of the BSA-NP. The SRAG were quantified by spectrophotometric method using 2, 4, 6-trinitrobenzenesulfonic acid(TNBS). Glycyrrhetinic acid(GA) hydrolyzed from GL, which was on the surface of BSA-NP-GL was assayed by HPLC after isolation by sephadex G-50. Both methods were used to verify the conjugation achieved. HPLC was used to determine surface density of GL on BSA-NP-GL.

RESULTSThe amount of SRAG of the BSA-NP-GL decreased by 19.6% compared with normal BSA-NP. The amount of GL molecule was 9.2% of the total determined SRAG of BSA-NP. The mean diameter of the BSA-NP-GL was 73 nm with round shape. The stability of BSA-NP-GL was constant when it was stored at 25 degrees C and 37 degrees C during 10 days.

CONCLUSIONBSA-NP-GL was successfully prepared, which is considered to establish an experimental foundation for further research on its ability for targeting to hepatocytes.

Cross-Linking Reagents ; chemistry ; Drug Delivery Systems ; Glycyrrhizic Acid ; chemistry ; Nanotechnology ; Particle Size ; Serum Albumin, Bovine ; administration & dosage ; chemistry ; ultrastructure ; Surface Properties ; Technology, Pharmaceutical ; methods

BSA liposomes were prepared with approximately 100 nm mean particle size under rather gentle experiment conditions, and two-colorimetric coomassie brilliant blue protein was employed to measure the free drug in the entrapped efficiency (EE%) determination of BSA liposomes. Gel filtration was used to measure the EE%, and several Sephadex gels were examined by the separation of liposomes and free drug. To determine the free drug, three methods were compared on two-colorimetric UV spectrophotography, Bradford and two-colorimetric coomassie brilliant blue, separately. Two-colorimetric coomassie brilliant blue process increased the accuracy and improved the sensitivity of the assay about 20-fold comparing with the Bradford method. Two-colorimetric coomassie brilliant blue assay appeared to be more sensitive and showed broader dynamic range to measure the free BSA in the EE% determination of BSA liposome.
Colorimetry ; Drug Carriers ; Drug Compounding ; Electrophoresis, Gel, Two-Dimensional ; Liposomes ; Particle Size ; Rosaniline Dyes ; Serum Albumin, Bovine ; administration & dosage ; analysis ; Spectrophotometry, Ultraviolet

AIMTo prepare cells scaffolds with the characteristics of sustained release of proteins.

METHODSChitosan scaffolds was prepared by freeze-drying. Porosity and water content of scaffolds were determined. Bovine serum album (BSA) was selected as a model protein. Poly (lactic-co-glycolic acid) (PLGA) microspheres were prepared by double emulsion solvent evaporation and encapsulated into chitosan scaffolds. The morphology of PLGA microspheres and various scaffolds were observed using scanning electron microscope. Release behavior of BSA from various chitosan scaffolds was investigated.

RESULTSThe chitosan scaffold represents porous. At the -70 degrees C of quenching temperature, the porosity and water content of chitosan scaffolds were 78.6% +/- 1.5% and 85.1% +/- 6.2%, respectively. PLGA microspheres can be uniformly encapsulated into scaffolds without any morphology change. Significant sustained release of BSA from PLGA microspheres encapsulated into scaffolds was obtained. The cumulative release at 168 h was only 33.5%, while that of BSA from chitosan scaffolds at 24 h was above 90%. The release behavior can be controlled by adjusting the amount of chitosan in scaffolds and the type of PLGA.

CONCLUSIONThe novel chitosan scaffolds encapsulating PLGA microspheres proved to be a promising cells scaffolds with controlling the release of growth factors in tissue engineering.

Chitosan ; administration & dosage ; chemistry ; Drug Carriers ; Freeze Drying ; methods ; Lactic Acid ; chemistry ; Microspheres ; Polyglycolic Acid ; chemistry ; Polymers ; chemistry ; Serum Albumin, Bovine ; metabolism ; Tissue Engineering ; methods

AIMTo investigate the formation mechanism, macromolecular drug loading capacity and release property of alginate-chitosan microcapsules (ACM).

METHODSACM was prepared by emulsification-gelation method and its formation mechanism was studied by DSC analysis. Using bovine serum albumin (BSA) as model drug, the drug loading and release properties of the microcapsules on macromolecular drug were investigated.

RESULTSThe results of DSC analysis showed that there is electrostatic interaction between materials encapsulated in the microcapsule. With the increase of BSA microcapsule ratio, the BSA loading percentage rose from 9.20% to 35.08%; and with the ascent of chitosan (CTS) concentration, the BSA loading percentage increased from 30.29% to 38.12%. The BSA microcapsules whowed a two-phase release in both 0.1 mol.L-1 HCl and phosphate buffer saline (pH 7.4). With the increase of CTS concentration, the BSA release more and more slowly in 0.1 mol.L-1 HCl.

CONCLUSIONSpheric and well-dispersed alginate-chitosan microcapsules were prepared. The microcapsule showed good loading capacity to BSA as well as sustained release to a certain degree.

Alginates ; chemistry ; Biopolymers ; Calorimetry, Differential Scanning ; Capsules ; Chitin ; analogs & derivatives ; chemistry ; Chitosan ; Delayed-Action Preparations ; Drug Carriers ; Drug Delivery Systems ; Serum Albumin, Bovine ; administration & dosage ; Technology, Pharmaceutical ; methods

The aim of this study is to prepare cationic biodegradable dextran microspheres loaded with tetanus toxoid (TT) and to investigate the mechanism of protein loading. Positively charged microspheres were prepared by polymerization of hydroxylethyl methacrylate derivatized dextran (dex-HEMA) and dimethyl aminoethyl methacrylate (DMAEMA) in an aqueous two-phase system. The loading of the microspheres with TT was based on electrostatic attraction. The net positive surface charge increased with increasing amounts of DMAEMA. Confocal images showed fluorescein isothiocyanate labeled bovine serum albumin (FITC-BSA) could penetrate into cationic dextran microspheres but not natural dextran microspheres. TT loading efficiency by post-loading was higher compared with by pre-loading. Even though TT is incorporated in the hydrogel network based on electrostatic interaction, still a controlled release can be achieved by varying the initial network density of the microspheres.
Delayed-Action Preparations ; Dextrans ; chemistry ; Drug Carriers ; chemistry ; Hydrogels ; chemistry ; Methacrylates ; chemistry ; Microscopy, Confocal ; Microspheres ; Particle Size ; Polymerization ; Serum Albumin, Bovine ; chemistry ; Tetanus Toxoid ; administration & dosage ; chemistry

This study sought to producte alginate sodium microsphere for controlled release bovine serum albumin(BSA) and to investigate the protein release profile of the BSA-alginate sodium microsphere in vitro, which threw some light on the angiogenesis of tissue engineering bone with vascular endothelial growth factor (VEGF) controlled release under stress. The BSA-alginate sodium microsphere was fabricated with W/O emulsification and ion cross-linking method using alginate sodium. The appearance, microsphere diameter and envelopment rate were detected, and the release characteristics of the BSA-alginate sodium microsphere in vitro was investigated. The alginate microsphere was found to be spherical in shape and evenly distributed. Its mean grain diameter was determined to be 230 +/- 60 microm, carrying capacity 80.3 microg/mg and envelopment rate 61%. Smooth controlled release in BSA-alginate sodium microsphere was shown to last more than 2 weeks. Alginate sodium proved an excellent biodegradable material for protein or polypeptide controlled release. The emulsification and ion cross-linking method was noted to be simple; it was propitious to the structural and functional stablility of protein or polypeptide, thus leading to the prolonged efficacious time of the microsphere.
Alginates ; administration & dosage ; chemistry ; Animals ; Cattle ; Delayed-Action Preparations ; chemical synthesis ; Drug Carriers ; Glucuronic Acid ; administration & dosage ; chemistry ; Hexuronic Acids ; administration & dosage ; chemistry ; Microspheres ; Serum Albumin, Bovine ; administration & dosage

The aim of this study is to investigate the critical factor affecting the properties of PLGA microspheres fabricated by a solid-in-oil-in-water (S/O/W) emulsion technique with BSA as a model protein. Prior to encapsulation, the BSA microparticles were fabricated by a modified freezing-induced phase separation method. The microparticles were subsequently encapsulated into PLGA microspheres by S/O/W emulsion method, then Motic BA200 biological microscope, confocal laser scanning microscope, scanning electron microscope were used to observe the structure of S/O/W emulsion and PLGA microspheres. The protein content extracted or released from BSA microspheres was measured by Bradford protein assay method. It was found that NaCl added in the outer aqueous phase effectively suppressed material exchange between the inner and outer phase of S/O/W emulsion. Then, the structure and permeability of obtained microspheres were influenced. As a result, with the increase of NaCl concentration in the outer aqueous phase, the encapsulation efficiency of microspheres significantly increased from 60% to more than 85%, the burst release of microspheres reduced from 70% to 20%, and the particle size decreased from 103 microm to 62 microm. Furthermore, the rehydration of encapsulated protein was also retarded and then integrity of BSA was successfully protected during encapsulation process. In vitro release test showed that BSA released from PLGA microspheres in a sustained manner for more than 30 days.
Delayed-Action Preparations ; Drug Compounding ; Emulsions ; chemistry ; Lactic Acid ; administration & dosage ; chemistry ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Microspheres ; Oils ; Particle Size ; Polyglycolic Acid ; administration & dosage ; chemistry ; Serum Albumin, Bovine ; administration & dosage ; chemistry ; Sodium Chloride ; chemistry ; Water

The aim is to evaluate the effect of ciprofloxacin and chloramphenicol on anti-BSA antibody production triggered by bovine albumin encapsulated in non-ionic surfactant vesicle, niosomes. Reverse phase evaporation method was adopted to entrap the antigen in colloidal carrier composed of Span 80 and Span 85 followed by simultaneous characterization for particle size, entrapment efficiency and in vitro release. The protein content was determined by Bradford method using UV Visible Spectrophotometer at 595 nm. Humoral immune response was measured in terms of systemic IgG antibody titre by ELISA method. Experimental data indicated that 7 : 3 molar ratio of Span 80 and cholesterol based niosomal formulation possessed maximum (39.8 +/- 2.9)% of soluble protein. Ciprofloxacin markedly (P < 0.05) decreased the antibody titre. In contrast, chloramphenicol did not reduce the antibody titre significantly in comparison to control group (P > 0.05). It is necessary to explore the effect of a vaccine antigen when a candidate is medicated with a therapeutic agent, which might help in programming a new drug management and vaccination programme.
Animals ; Antibody Formation ; drug effects ; Chloramphenicol ; administration & dosage ; pharmacology ; Ciprofloxacin ; administration & dosage ; pharmacology ; Drug Carriers ; Hexoses ; Immunoglobulin G ; blood ; Liposomes ; Male ; Particle Size ; Rats ; Rats, Wistar ; Serum Albumin, Bovine