NMR cryoporometry characterisation studies of the relation between drug release profile and pore structural evolution of polymeric nanoparticles.
Bottom Line: PLGA/PLA polymeric nanoparticles could potentially enhance the effectiveness of convective delivery of drugs, such as carboplatin, to the brain, by enabling a more sustained dosage over a longer time than otherwise possible.For a core-coat nanoparticle formulation, the development of smaller nanopores, following an extended induction period with no structural change, was associated with the onset of substantial drug release.Hence, the specific reasons for the effectiveness of the synthesis route, for obtaining core-coat nanoparticles with delayed release, have been elucidated.
Affiliation: Department of Chemical and Environmental Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK.Show MeSH
Related in: MedlinePlus
Mentions: Batches A and B were identical except that batch A contained Nile Red, while batch B contained carboplatin. The pore structural evolution of nanoparticles from batch A following exposure to water vapour, or immersion in aCSF solution, was studied using microscopy techniques or NMR cryoporometry respectively. These two methods enabled the study the nanoparticle structure over both very short and long evolutionary time scales, i.e. of the order of minutes and days. Nanoparticles from batch A were exposed to increasing levels of relative humidity (RH), from ∼5% to 100%, to study the interaction of the sample with water vapour. At ∼100% RH, a gel or paste formation was observed. Water vapour condensed in particular isolated regions of the sample, and then began flooding the sample, leading to the formation of a suspension, as seen in Fig. 2(a). Fig. 2(a) was obtained after exposing the same to water vapour for ∼2 h. A few minutes later, a thick gel had formed, as seen in Fig. 2(b). Upon drying the sample to ∼48% RH and then to 21% RH, the paste remained visible.
Affiliation: Department of Chemical and Environmental Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK.