Study on physiochemical structure and in vitro release behaviors of doxycycline‐loaded PCL microspheres

Abstract

This study aimed to develop drug delivery system of doxycycline-loaded polycaprolactone (PCL) microspheres. The investigated microsphere formulation can be considered for local application in bone infections and degenerative joint diseases, which generally require long-term treatments via systemic drugs. PCL-14 kDa and 65 kDa were used in microsphere preparation. Before release, the microspheres were characterized by scanning electron microscopy, differential scanning calorimetry, and X-ray photoelectron spectroscopy. The mean particle size of microspheres was in the range of 74-122 mm and their drug loadings ranged between 10 and 30%. In vitro release profiles were described using the Higuchi and the Korsmeyer-Peppas equations. Diffusion model was applied to experimental data for estimating diffusion coefficients of microspheres; calculated as between 4.5 3 10 210 and 9.5 3 10 210 cm 2 /s.Although long-term release from microspheres of PCL-14 kDa obeyed diffusion model, PCL-65 kDa microspheres showed this tendency only for some period. Modeling studies showed that the drug release mechanism was mainly dependent on loading and molecular weight differences. Release behavior of PCL-65 kDa microspheres, however, might be better represented by derivation of a different equation to model for the total release period.

Development of tunable biodegradable polyhydroxyalkanoates microspheres for controlled delivery of tetracycline for treating periodontal disease

“…In fact, when the P(HB-50HV) copolymer was used, it resulted in sub-micron particles with average size around 329.90 6 8.71 nm. 60,61 Our findings are also in accordance with a study performed by Wang et al 61 that found increasing HV content in P(HB-HV) copolymer decreased the average size and size distribution of ibuprofen-loaded P(HB-HV) microparticles. The drastic decrease in particle size when using P(HB-50HV) might be due to the relative lower viscosity of the organic P(HB-50HV) solution used in the emulsification step compared to PHB and other P(HB-HV) polymers with lower %HV content.…”

“…Several studies have reported similar findings where well dispersed emulsion droplets and smaller size particles could form in the PVA aqueous phase when using a lower viscosity organic polymer solution. 60,61 Our findings are also in accordance with a study performed by Wang et al 61 that found increasing HV content ARTICLE WILEYONLINELIBRARY.COM/APP in P(HB-HV) copolymer decreased the average size and size distribution of ibuprofen-loaded P(HB-HV) microparticles. This was attributed to more efficient dispersion of the organic phase in the aqueous medium.…”

Preparation and characterization of biomedical collagen–chitosan scaffolds with entrapped ibuprofen and silver nanoparticles

“…Crystallinity of drugs has a strong effect on the drug release kinetics and degradation behavior . For examination of crystal state of ibuprofen and silver in CLH scaffold, the XRD was applied (Fig.…”

Polycaprolactone as Drug Carrier for an Antifungal Agent

“…Since AmB is a hydrophobic drug, it is retained inside the core of the polymeric matrix after encapsulation not near the surface of particles as in the case of hydrophilic drugs. As a result, it requires more time to diffuse to the aqueous buffer medium and to be released [8][9][10]15 .…”

“…Degradation of PCL in comparison to the other polyesters is very slow, which is mainly needed for long-term delivery extending over a period of more than one year. In addition, the non-toxic products from its biodegradation also contribute in being favorable in delivery vehicles 8,9 . Several drugs or biological molecules have been encapsulated into PCL microspheres or nanospheres such as Nifedipine, Indomethacin, Taxol, antigens, hormones, steroids, etc.…”