No abstract

We report charge-switching ionic nanocomplexes comprised of glycol chitosan grafted with 2,3-dimethylmaleic acid (DMA) (denoted as 'GCS-g-DMA' hereafter) and a proapoptotic peptide. This system allowed for improved peptide delivery to tumor sites via a mechanism of selective peptide release when the pH was dropped from 7.4 to 6.8.

No abstract

In this study, a poly(L-lactic acid)-b-poly(ethylene glycol) (PLLA-b-PEG) diblock copolymer modified with a sialic acid derivative (methyl-b-neuraminic acid: mNA) was prepared for the development and application of a therapeutic nanosystem with multifunctionality. The terminal carboxyl group of PEG was coupled with mNA via N,N'-dicyclohexyl carbodiimide (DCC)-and N-hydroxysuccinimide (NHS)-mediated amide formation. Polymeric micelles were formed using the diafilteration method at pH 7.4, which resulted in a micelle self-assembly with the PLLA block at the core and PEG-mNA block on the shell. An anionic charge was formed on the surface of the micelle at physiological pH (~pH 7.4) due to mNA. Amantadine (AMT), a model drug for antiviral treatment, was loaded into the micellar core. These micelles were expected to exhibit multiple therapeutic activity that originated from the antiviral activity of mNA on the shell and the sustained release of AMT from the micellar core.