Enhancement of oral bioavailability of poorly water-soluble drugs by poly(ethylene glycol)-block-poly(alkyl acrylate-co-methacrylic acid) self-assemblies

Polymeric micelles: authoritative aspects for drug delivery

“…A 15-250-fold higher uptake efficiency of particles $100 nm in diameter by the gastrointestinal tract was noted than that of the micrometer-sized particles [132]. PEG-bpoly(alkyl acrylate-co-methacrylic acid) micelles entrapping fenofibrate exhibited enhanced oral bioavailability as compared to fenofibrate suspension [261]. Han et al studied the pharmacokinetics and biodistribution of Pluronic P123 micelles loaded with paclitaxel [262].…”

Phase diagram and dissolution studies of the fenofibrate–acetylsalicylic acid system

“…Poor water solubility and slow dissolution are often the main reasons for the rejection of potentially active drugs [10,11]. Several approaches have been employed to overcome this problem, such as the preparation of solid dispersions of an active agent in a biologically inert matrix [12][13][14], drug dissolution in the presence of polymeric micelles in the dissolution medium [15], addition of surfactants [15][16][17][18], micronization-particle size reduction to nano-or microsize [19][20][21], melt granulation technique [22,23] and formation of eutectics [24,25], including drug-polymer component systems [26,27].…”

Polymeric Micelles

“…Examples of passive stimuli that can be exploited include locally decreased pH in tumor and endosomes, elevated glutathione concentrations inside cells or local enzyme overexpression (Ge and Liu 2013;Rijcken et al 2007b). In case of oral delivery, the changes in pH throughout the gastrointestinal tract offer a further opportunity (Sant et al 2004;Jones et al 2003;Sant et al 2005). pH triggerable polymeric micelles can be categorised in two groups: one uses pH-dependent ionization of weak acid or weak base groups to induce a hydrophobic to hydrophilic conversion of the core-forming block resulting in micellar disassembly; the other one exploits pH-sensitive cleavage of linkers leading to specific release of the API.…”