1. Doxycycline delivery from PLGA microspheres prepared by a modified solvent removal method
- Author
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Danya M. Lavin, Stacia Furtado, Amy Chang, Roshni S. Patel, Kenneth Estrellas, Cheng Tian, Daniel Y. Cho, and Edith Mathiowitz
- Subjects
Materials science ,Drug Compounding ,Kinetics ,Pharmaceutical Science ,Bioengineering ,Nanotechnology ,Crystallography, X-Ray ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Differential scanning calorimetry ,Drug Delivery Systems ,Polylactic Acid-Polyglycolic Acid Copolymer ,Spectroscopy, Fourier Transform Infrared ,Lactic Acid ,Physical and Theoretical Chemistry ,Fourier transform infrared spectroscopy ,Particle Size ,Calorimetry, Differential Scanning ,Organic Chemistry ,Biodegradable polymer ,Microspheres ,Anti-Bacterial Agents ,Solvent ,PLGA ,chemistry ,Delayed-Action Preparations ,Doxycycline ,Drug delivery ,Microscopy, Electron, Scanning ,Solvents ,Emulsions ,Particle size ,Hydrophobic and Hydrophilic Interactions ,Nanospheres ,Polyglycolic Acid ,Nuclear chemistry - Abstract
We report on the development of a modified solvent removal method for the encapsulation of hydrophilic drugs within poly(lactic-co-glycolic acid) (PLGA). Using a water/oil/oil double emulsion, hydrophilic doxycycline was encapsulated within PLGA spheres with particle diameters ranging from approximately 600 nm to 19 µm. Encapsulation efficiencies of up to 74% were achieved for theoretical loadings from 1% to 10% (w/w), with biphasic release over 85 days with nearly complete release at the end of this time course. About 1% salt was added to the formulations to examine its effects on doxycycline release; salt modulated release only by increasing the magnitude of initial release without altering kinetics. Fourier transform infrared spectroscopy indicated no characteristic differences between doxycycline-loaded and control spheres. Differential scanning calorimetry and X-ray diffraction suggest that there may be a molecular dispersion of the doxycycline within the spheres and the doxycycline may be in an amorphous state, which could explain the slow, prolonged release of the drug.
- Published
- 2012