muramidase and glycofurol

The prilling process proposes a microparticle formulation easily transferable to the pharmaceutical production, leading to monodispersed and highly controllable microspheres. PLGA microspheres were used for carrying an encapsulated protein and adhered stem cells on its surface, proposing a tool for regeneration therapy against injured tissue. This work focused on the development of the production of PLGA microspheres by the prilling process without toxic solvent. The required production quality needed a complete optimization of the process. Seventeen parameters were studied through experimental designs and led to an acceptable production. The key parameters and mechanisms of formation were highlighted.

Topics: Animals; Chemistry, Pharmaceutical; Chickens; Drug Design; Lactic Acid; Micrococcus; Microspheres; Muramidase; Particle Size; Polyethylene Glycols; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer

The aim of this work was to elaborate formulation strategies to encapsulate a protein into biodegradable polymeric particles for sustained release purpose. In this paper, two encapsulation methods will be presented, one dealing with a phase separation phenomenon while the other involving an emulsification/extraction process in CO(2) medium. In those methods, only non-volatile injectable solvents such as glycofurol or isosorbide dimethyl ether were used to dissolve the polymer. Moreover, experimental designs were built up to help us to go further in the understanding of the processes and to better predict output responses in design space. Spherical particles were successfully generated with a satisfactory encapsulation yield. Further characterization steps such as in vitro, in vivo releases will be carried out to validate the interest of our encapsulation methods in the development of drug delivery systems.

Topics: Carbon Dioxide; Chemistry, Pharmaceutical; Delayed-Action Preparations; Drug Delivery Systems; Emulsions; Isosorbide; Lactic Acid; Microspheres; Muramidase; Polyethylene Glycols; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Polymers; Solvents

Proteins were precipitated to ensure their stability upon subsequent encapsulation within PLGA microspheres. Spherical, nanosized protein particles were formed by the addition of a salt (sodium chloride) and a water-miscible organic solvent (glycofurol) to protein solutions. Various process parameters were modified to optimize the precipitation efficiency of four model proteins: lysozyme, alpha-chymotrypsin, peroxidase and beta-galactosidase. As monitored by enzymatic activity measurement of the rehydrated particles, conditions to obtain more than 95% of reversible precipitates were defined for each protein. The study of the structure of the rehydrated particles by absorbance spectroscopy, fluorescence spectroscopy and circular dichroism showed an absence of structural-perturbation after precipitation. Protein particles were then microencapsulated within PLGA microspheres using s/o/w technique. The average encapsulation yield was around 80% and no loss of protein activity occurred after the encapsulation step. Additionally, a lysozyme in vitro release study showed that all of the released lysozyme was biologically active. This method of protein precipitation is appropriate for the encapsulation in PLGA microspheres of various proteins without inactivation.

Topics: Animals; beta-Galactosidase; Chemical Precipitation; Chemistry, Pharmaceutical; Chymotrypsin; Drug Carriers; Drug Compounding; Enzyme Stability; Enzymes; Kinetics; Lactic Acid; Microspheres; Muramidase; Oils; Peroxidase; Polyethylene Glycols; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; Protein Conformation; Sodium Chloride; Solubility; Solvents; Technology, Pharmaceutical; Water