Highly efficient nanomedicines assembled via polymer–drug multiple interactions: Tissue-selective delivery carriers

Poly(ε-benzyloxycarbonyl-L-lysine)-grafted branched polyethylenimine as efficient nanocarriers for indomethacin with enhanced oral bioavailability and anti-inflammatory efficacy

“…Notably, the DSC thermogram of raw IND powder exhibited a sharp melting endothermic peak at 160°C, which corresponded to the melting point for the c-form IND [21]. When a small amount of IND was incorporated into the nanoparticles, no obvious peaks were observed, suggesting that IND was molecularly or amorphously dispersed in the assemblies [11,21]. As the feeding ratio of IND increased, a common shifted endothermic peak was observed approximately 140°C due to the fusion of the eutectic mixture of IND/PEI-g-PZLL [21].…”

“…Thus, PP1 exhibited a stronger crystallization inhibition effect toward IND than did PP2. The mechanism of the crystallization inhibition is related to the extent of interactions between drug molecules and polymers [11,22]. The stronger crystallization inhibition effect of PP1 suggested that it could provide stronger interactions with IND.…”

“…Linear PEI derivatized with cetyl chains and quaternary ammonium groups has been reported to encapsulate high levels of hydrophobic drugs and facilitate the absorption of drugs within the GI tract [10]. Recently, b-cyclodextrin-conjugated branched PEI (PEI-CD) was used to entrap indomethacin (IND) to construct a highly efficient oral delivery system [11][12][13]. These nanomedicines were created via intermolecular interactions between the polymers and drug molecules, including hydrophobic interactions, host-guest recognition, hydrogen bonding, and electrostatic forces.…”

“…These nanomedicines were created via intermolecular interactions between the polymers and drug molecules, including hydrophobic interactions, host-guest recognition, hydrogen bonding, and electrostatic forces. The resultant delivery platforms exhibited high loading capacities, improved oral bioavailability and enhanced therapeutic activity on paw edemas in rats [11]. However, the use of PEIs as oral drug delivery carriers has been hindered, at least partially, because the use of higher molecular weight PEI leads to improved efficiency but also increased cytotoxicity.…”

“…The nanoscale size and temporal stability of these polymeric micelles facilitate drug loading. (3) The diverse functionalities in the PEI-g-PZLL structure are favorable for the encapsulation of drug molecules through a number of intermolecular interactions, including hydrophobic interactions, p-p stacking, hydrogen bonding and electrostatic forces, which are beneficial to the amorphization, dissolution rate, and bioavailability of the drug molecules [11].…”