An in vitro study of plasticized poly(lactic-co-glycolic acid) films as possible guided tissue regeneration membranes: Material properties and drug release kinetics

ABSTRACTIncreased functions of osteoblasts (bone-forming cells) have been demonstrated on nanophase compared to conventional ceramics (specifically, alumina, titania, and hydroxyapatite), polymers (such as poly-lactic-glycolic acid and polyurethane), carbon nanofibers, and composites thereof. Nanophase materials are materials that simulate dimensions of constituent components of bone since they possess particle or grain sizes less than 100 nm. However, to date, interactions of osteoblasts on nanophase compared to conventional metals remain to be elucidated. For this reason, the objective of the present in vitro study was to design, fabricate, and evaluate osteoblast adhesion on nanophase metals (specifically, Ti and Ti6Al4V). Results of this study provided the first evidence of increased osteoblast adhesion on nanophase compared to conventional Ti-based metals. Moreover, directed osteoblast adhesion was observed preferentially at metal particle boundaries. It is speculated that since more particle boundaries were created through the use of nanophase compared to conventional metals, increased osteoblast adhesion resulted. Because adhesion is a necessary prerequisite for subsequent functions of osteoblasts (such as deposition of calcium-containing mineral), the present study suggests that Ti-based nanophase metals should be further considered for orthopedic implant applications.

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In vitro study of sirolimus release from nonwoven PLLA matrices

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2018-0142 ◽

2018 ◽

Vol 4 (1) ◽

pp. 591-594

Author(s):

Sabine Illner ◽

Stefanie Kohse ◽

Claudia Michaelis ◽

Thomas Reske ◽

Niels Grabow ◽

...

Keyword(s):

Drug Release ◽

Release Kinetics ◽

Volume Ratio ◽

In Vitro Study ◽

Complete Wetting ◽

In Vitro Drug Release ◽

Spray Coatings ◽

Plasma Pretreatment ◽

Predetermined Time

AbstractSirolimus incorporated nonwoven polymer matrices were fabricated via electrospinning. Release kinetics considering different fiber diameters and layer thicknesses were investigated. In vitro drug release profiles were evaluated by measuring the drug concentration in an established drug release medium (0.9% saline solution with additives, not buffered) at predetermined time points. Furthermore, an NH3-plasma pretreatment was examined to ensure complete wetting from the beginning of the study. In comparison to thin drug-loaded PLLA spray coatings it was shown that the release of sirolimus is diffusion- and degradation-controlled regardless of the surface-to-volume ratio, though fiber diameters or a hydrophilization can affect its release kinetics.

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Poly(3-Hydroxybutyrate)-Based Nanoparticles for Sorafenib and Doxorubicin Anticancer Drug Delivery

International Journal of Molecular Sciences ◽

10.3390/ijms21197312 ◽

2020 ◽

Vol 21 (19) ◽

pp. 7312 ◽

Cited By ~ 1

Author(s):

György Babos ◽

Joanna Rydz ◽

Michal Kawalec ◽

Magdalena Klim ◽

Andrea Fodor-Kardos ◽

...

Keyword(s):

Drug Release ◽

Glycolic Acid ◽

Release Kinetics ◽

Solvent Evaporation Method ◽

Poly Ethylene Glycol ◽

Anticancer Drug Delivery ◽

Poly Ethylene ◽

Average Size ◽

Dual Drug

Dual drug-loaded nanotherapeutics can play an important role against the drug resistance and side effects of the single drugs. Doxorubicin and sorafenib were efficiently co-encapsulated by tailor-made poly([R,S]-3-hydroxybutyrate) (PHB) using an emulsion–solvent evaporation method. Subsequent poly(ethylene glycol) (PEG) conjugation onto nanoparticles was applied to make the nanocarriers stealth and to improve their drug release characteristics. Monodisperse PHB–sorafenib–doxorubicin nanoparticles had an average size of 199.3 nm, which was increased to 250.5 nm after PEGylation. The nanoparticle yield and encapsulation efficiencies of drugs decreased slightly in consequence of PEG conjugation. The drug release of the doxorubicin was beneficial, since it was liberated faster in a tumor-specific acidic environment than in blood plasma. The PEG attachment decelerated the release of both the doxorubicin and the sorafenib, however, the release of the latter drug remained still significantly faster with increased initial burst compared to doxorubicin. Nevertheless, the PEG–PHB copolymer showed more beneficial drug release kinetics in vitro in comparison with our recently developed PEGylated poly(lactic-co-glycolic acid) nanoparticles loaded with the same drugs.

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