Biomaterial Database

Preparation and evaluation of sustained release cross-linked chitosan microspheres containing phenobarbitone. 1998

A A al-Helw, and A A Al-Angary, and G M Mahrous, and M M al-Dardari

Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.

Chitosan microspheres containing phenobarbitone were successfully prepared by glutaraldehyde cross-linking of an aqueous acetic acid dispersion of chitosan in light liquid paraffin containing sorbitan mono-oleate as a stabilizing agent. Uniform and spherical microspheres, with a loading efficiency up to 57.2%, could be prepared depending on the preparation conditions. The main parameters affecting the preparation and the performance of the prepared microspheres were the molecular weight and concentration of chitosan as well as the concentration of the used stabilizing agent. The incorporation of citric acid into the microspheres was found to increase the formation of a water-soluble gel when the microspheres come in contact with the dissolution medium increasing the rate of drug release. The particle size was shifted towards smaller diameters with increased concentration of sorbitan mono-oleate, up to 4.0% v/v, by use of a lower concentration of chitosan (1.0% w/v) and chitosan with low molecular weight. Rapid initial drug release (20-30% of the incorporated drug) was exhibited in all the prepared microspheres followed by slow release of the remaining amount of the drug. The release rate of the drug from the microspheres prepared from high molecular weight chitosan was slow in comparison with that prepared from medium and low molecular weight chitosan. High concentrations of sorbitan mono-oleate increased the rate of drug release.

UI	MeSH Term	Description	Entries
D008863	Microspheres	Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.	Latex Beads,Latex Particles,Latex Spheres,Microbeads,Bead, Latex,Beads, Latex,Latex Bead,Latex Particle,Latex Sphere,Microbead,Microsphere,Particle, Latex,Particles, Latex,Sphere, Latex,Spheres, Latex
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010316	Particle Size	Relating to the size of solids.	Particle Sizes,Size, Particle,Sizes, Particle
D010634	Phenobarbital	A barbituric acid derivative that acts as a nonselective central nervous system depressant. It potentiates GAMMA-AMINOBUTYRIC ACID action on GABA-A RECEPTORS, and modulates chloride currents through receptor channels. It also inhibits glutamate induced depolarizations.	Phenemal,Phenobarbitone,Phenylbarbital,Gardenal,Hysteps,Luminal,Phenobarbital Sodium,Phenobarbital, Monosodium Salt,Phenylethylbarbituric Acid,Acid, Phenylethylbarbituric,Monosodium Salt Phenobarbital,Sodium, Phenobarbital
D002686	Chitin	A linear polysaccharide of beta-1->4 linked units of ACETYLGLUCOSAMINE. It is the second most abundant biopolymer on earth, found especially in INSECTS and FUNGI. When deacetylated it is called CHITOSAN.
D003432	Cross-Linking Reagents	Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.	Bifunctional Reagent,Bifunctional Reagents,Cross Linking Reagent,Crosslinking Reagent,Cross Linking Reagents,Crosslinking Reagents,Linking Reagent, Cross,Linking Reagents, Cross,Reagent, Bifunctional,Reagent, Cross Linking,Reagent, Crosslinking,Reagents, Bifunctional,Reagents, Cross Linking,Reagents, Cross-Linking,Reagents, Crosslinking
D003692	Delayed-Action Preparations	Dosage forms of a drug that act over a period of time by controlled-release processes or technology.	Controlled Release Formulation,Controlled-Release Formulation,Controlled-Release Preparation,Delayed-Action Preparation,Depot Preparation,Depot Preparations,Extended Release Formulation,Extended Release Preparation,Prolonged-Action Preparation,Prolonged-Action Preparations,Sustained Release Formulation,Sustained-Release Preparation,Sustained-Release Preparations,Timed-Release Preparation,Timed-Release Preparations,Controlled-Release Formulations,Controlled-Release Preparations,Extended Release Formulations,Extended Release Preparations,Slow Release Formulation,Sustained Release Formulations,Controlled Release Formulations,Controlled Release Preparation,Controlled Release Preparations,Delayed Action Preparation,Delayed Action Preparations,Formulation, Controlled Release,Formulations, Controlled Release,Prolonged Action Preparation,Release Formulation, Controlled,Release Formulations, Controlled,Sustained Release Preparation,Timed Release Preparation,Timed Release Preparations
D004337	Drug Carriers	Forms to which substances are incorporated to improve the delivery and the effectiveness of drugs. Drug carriers are used in drug-delivery systems such as the controlled-release technology to prolong in vivo drug actions, decrease drug metabolism, and reduce drug toxicity. Carriers are also used in designs to increase the effectiveness of drug delivery to the target sites of pharmacological actions. Liposomes, albumin microspheres, soluble synthetic polymers, DNA complexes, protein-drug conjugates, and carrier erythrocytes among others have been employed as biodegradable drug carriers.	Drug Carrier
D004339	Drug Compounding	The preparation, mixing, and assembly of a drug. (From Remington, The Science and Practice of Pharmacy, 19th ed, p1814).	Drug Formulation,Drug Preparation,Drug Microencapsulation,Pharmaceutical Formulation,Compounding, Drug,Formulation, Drug,Formulation, Pharmaceutical,Microencapsulation, Drug,Preparation, Drug
D005976	Glutaral	One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.	Glutaraldehyde,Cidex,Diswart,Gludesin,Glutardialdehyde,Glutarol,Korsolex,Novaruca,Sekumatic,Sonacide,Sporicidin