Loading and Release of Small Hydrophobic Molecules in Multilayer Films Based on Amphiphilic Polysaccharides

Abstract

We report on the loading and release behaviors of polyelectrolyte multilayers based on hydrophobically modified carboxymethylpullulan (CMP) derivatives and poly(ethyleneimine) (PEI) toward hydrophobic dye. The dye-loaded films are obtained according to two different protocols: (i) the postdiffusion approach, which involves the diffusion of the dye within preassembled self-assemblies, and (ii) the precomplexation method, which requires the formation of a water-soluble amphiphilic CMP derivative-dye complex before the multilayer buildup. In both cases, we provide clear evidence for the entrapment of the dye in hydrophobic nanoreservoirs resulting from the aggregation of decyl pendent groups grafted on CMP chains. We show that the loading capacity of the multilayers, as well as their release behavior, can be tuned by varying the grafting degree of CMP chains. Moreover, we demonstrate the possibility to trigger the subsequent release of the loaded dye molecules by varying the composition of the surrounding solution.

Selective sulfation of carrageenans and the influence of sulfate regiochemistry on anticoagulant properties

“…Along with the esterified diad, G4S-DA units were observed as major constituent (63%) in Sample 4, as expected considering the reaction optimization (Table S1). It is worth noting that the esterified diad constitutes a valuable polymer, since amphiphilic polysaccharides have attracted wide interest due to their use in nanotechnology areas such as drug delivery and surface coating (Durand, Marie, Rotureau, Leonard, & Dellacherie, 2004;Guyomard, Nysten, Muller, & Glinel, 2006;Lu, Zhang, & Liu, 2008). The conversion of Sample 4 into 5 proceeded as depicted in Scheme 1.…”

Hydrophobic Shell Loading of Biopolyelectrolyte Capsules

“…In a fi rst step, we tested the ability of the different quaternized CHI and alkylated HA self-assemblies to entrap the poorly soluble dye nile red (NR) [ 20 ] and to reveal the presence of hydrophobic nanodomains. To this end, NR was pre-complexed with the alkylated HA derivatives and the fl uorescence of the (QCHI/HA x C10) fi lms was followed step-bystep ( Figure 2 ).…”

Polyelectrolyte Multilayer Nanoshells With Hydrophobic Nanodomains for Delivery of Paclitaxel

“…Hammond et al used a cyclodextrin-drug complex assembled with a hydrolysable synthetic polymer (a polyβamino ester) to load and subsequently deliver the antiinflammatory drug Diclofenac [2]. Another strategy for incorporation of hydrophobic molecules within PEMs involved the use of amphiphilic polysaccharides associated with a synthetic polyelectrolyte, such as poly(ethylene imine) [34,35]. However, this strategy may suffer from problems associated with controlled release of the drug molecules at physiological pH.…”