Preparation of nanoparticles consisted of poly(l-lactide)–poly(ethylene glycol)–poly(l-lactide) and their evaluation in vitro

Characterization of progesterone loaded biodegradable blend polymeric nanoparticles

“…All recovery yields presented high values with no significant difference (p>0.05) meaning that no loss of progesterone during the encapsulation procedure could be observed. SOUZA et al (2011) results obtained at the present research can be explained by the hydrophobic characteristics of PLLA, PCL and PHBV that present more affinity with progesterone than with the copolymer used by MATSUMOTO et al (1999). The addition of hydrophilic segments (PEG) into the hydrophobic PLA homopolymer reduced the encapsulation efficiency.…”

“…Biopolymer micro and nanoparticles have been proposed as an alternative to encapsulate progesterone (JAMEELA et al, 1998;LEMOS-SENNA et al, 1998;MATSUMOTO et al, 1999;LATHA et al, 2000;SILVA et al, 2006;SALEM, 2010). It is worth noting that besides the controlled delivery, encapsulation also provides protection from premature degradation during handling and storage before use, enhancement of absorption and bioavailability, improved retention time inside the organism and improvement of intracellular penetration (KUMARI et al, 2010).…”

Drug transport to brain with targeted nanoparticles

“…Drug release from biodegradable polymeric nanoparticles depends on the Fickian diffusion through the polymer matrix and on the degradation rate of the polymer. The prediction of the release profile is complex because it results from a combined effect of various parameters: solid-state drug polymer solubility 98 and drug-polymer interactions, 55,91,92,100 polymer degradation rate, 61 block copolymer molecular weight and polydispersity, 103 PEG content and molecular weight, 89,91,103 water uptake by nanoparticles 48 and drug solubility in the biological medium. In most studies, in vitro release profiles are characterized by an initial fast release (burst) of drug close to or at the surface followed by a sustained release.…”

“…In most studies, in vitro release profiles are characterized by an initial fast release (burst) of drug close to or at the surface followed by a sustained release. 91,92,103 Removing the low molecular weight fraction from the polymer was shown to reduce the initial burst of drug release. 103 Depending on formulations in vitro, drug releases last from a few hours 84,91,92 or a few days 87 to several weeks.…”

“…91,92,103 Removing the low molecular weight fraction from the polymer was shown to reduce the initial burst of drug release. 103 Depending on formulations in vitro, drug releases last from a few hours 84,91,92 or a few days 87 to several weeks. 61,84,88,90 Administered locally, betamethasone sodium phosphateloaded PLGA nanoparticles were efficient at controlling inflammation over at least 3 weeks in a rabbit model of arthritis, compared with one day for the solution.…”