Long-term controlled release of PLGA microparticles containing antidepressant mirtazapine

Abstract

The aim of the study was to prepare PLGA microparticles for prolonged release of mirtazapine by o/w solvent evaporation method and to evaluate effects of PVA concentration and organic solvent choice on microparticles characteristics (encapsulation efficiency, drug loading, burst effect, microparticle morphology). Also in vitro drug release tests were performed and the results were correlated with kinetic model equations to approximate drug release mechanism. It was found that dichloromethane provided microparticles with better qualities (encapsulation efficiency 64.2%, yield 79.7%). Interaction between organic solvent effect and effect of PVA concentration was revealed. The prepared samples released the drug for 5 days with kinetics very close to that of zero order (R(2 )= 0.9549 - 0.9816). According to the correlations, the drug was probably released by a combination of diffusion and surface erosion, enhanced by polymer swelling and chain relaxation.

Biodegradable nitric oxide precursor-loaded micro- and nanoparticles for the treatment of Staphylococcus aureus biofilms

“…In this context, n values between 0.45 and 0.89 are indicative of non-Fickian release which refers to a combination of both diffusion and erosion drug release mechanisms. 49 The observed n values for the release of ISMN from PLGA-MPs and PLGA-NPs of 0.74 and 0.66 respectively (R 2 4 0.95) is confirmation of non-Fickian behaviour. Such release characteristics could be attributed to the increase in strong entanglement bonds between the polymer matrixes which resisted the erosion by the dissolution medium in the initial hours of ISMN release.…”

Selective Androgen Receptor Modulator Microparticle Formulation Reverses Muscle Hyperalgesia in Mouse Model of Widespread Muscle Pain

“…Powder X-ray diffraction is used to determine whether a compound is in a crystalline or an amorphous state. When a crystalline drug is encapsulated in a microparticle formulation it loses its crystalline properties and exists in a molecularly dispersed (amorphous) form ( 36 ). The diffraction patterns of the SARM-loaded PLGA microparticles (F1 and F2) (Fig.…”

Long-Term Sustained Drug Delivery via 3D Printed Masks for the Development of a Heparin-Loaded Interlayer in Vascular Tissue Engineering Applications

“…The purpose of controlling the UV exposure with masks during crosslinking is to create unique heparin release profiles. The loading efficiency in heparin-loaded gelMA is extremely high when compared to other methods of drug encapsulation. ,, There is no clear change in loading efficiency caused by the masks or gelMA concentration, but both of these factors lead to differences in heparin release. The more gradual release in 7% 30 min No Mask corresponds to higher elastic modulus measured for this group, while the lower elastic moduli measured for 7% 30 min Mask 1 and 7% 30 min Mask 2 presented faster heparin release.…”