Dextran Nanoparticle Synthesis and Properties.

Dextran is widely exploited in medical products and as a component of drug-delivering nanoparticles (NPs). Here, we tested whether dextran can serve as the main substrate of NPs and form a stable backbone. We tested dextrans with several molecular masses under several synthesis conditions to optimize NP stability. The analysis of the obtained nanoparticles showed that dextran NPs that were synthesized from 70 kDa dextran with a 5% degree of oxidation of the polysaccharide chain and 50% substitution with dodecylamine formed a NP backbone composed of modified dextran subunits, the mean diameter of which in an aqueous environment was around 100 nm. Dextran NPs could be stored in a dry state and reassembled in water. Moreover, we found that different chemical moieties (e.g., drugs such as doxorubicin) can be attached to the dextran NPs via a pH-dependent bond that allows release of the drug with lowering pH. We conclude that dextran NPs are a promising nano drug carrier

HeLa cell viability after 24h incubation with doxorubicin, Dex-NPs, Dox-NPs and rDox-NPs.

<p>HeLa cell viability after 24h incubation with doxorubicin, Dex-NPs, Dox-NPs and rDox-NPs.</p

Scheme of dextran modifications.

<p>Step 1: Oxidation, leading to opening of the glucose rings. Step 2: Schiff base formation between glucose carbonyl group and aliphatic amine.</p

Diagram of nanoparticles synthesis strategy.

<p>Diagram of nanoparticles synthesis strategy.</p

Mobility-equivalent diameter distribution of nanoparticles.

<p>Dex-NPs with a 55% (A) and 33% (B) degree of substitution (10 μg/ml and 100 μg/ml) referred to pure dextran 70 kDa (7μg/ml). (C) Dex-NPs with a 33% degree of substitution (10μg/ml) with and without cryoprotectant referred to pure dextran 70 kDa (7μg/ml). (D) Dox-NPs with a 33% degree of substitution (10 μg/ml; 33 μg/ml and 100 μg/ml). Mean n = 5.</p