Acidic pH-Responsive Nanogels as Smart Cargo Systems for the Simultaneous Loading and Release of Short Oligonucleotides and Magnetic Nanoparticles

Istituto Italiano di Tecnologia, via Morego 30, 16163, Genova, Italy.
Langmuir (Impact Factor: 4.46). 03/2010; 26(12):10315-24. DOI: 10.1021/la1004819
Source: PubMed

ABSTRACT Smart materials able to sense environmental stimuli can be exploited as intelligent carrier systems. Acidic pH-responsive polymers, for instance, exhibit a variation in the ionization state upon lowering the pH, which leads to their swelling. The different permeability of these polymers as a function of the pH could be exploited for the incorporation and subsequent release of previously trapped payload molecules/nanoparticles. We provide here a proof of concept of a novel use of pH-responsive polymer nanostructures based on 2-vinylpyridine and divinylbenzene, having an overall size below 200 nm, as cargo system for magnetic nanoparticles, for oligonucleotide sequences, as well as for their simultaneous loading and controlled release mediated by the pH.

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