Metastable state of amphiphilic polysaccharide solutions

Simon, Sébastien; Mocanu, Georgeta; Picton, Luc; Cerf, Didier Le; Müller, G.

doi:10.1515/epoly.2004.4.1.408

Cited by 4 publications

(6 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…26 In a previous paper we have demonstrated that the ester linkages for hydrophobically modified CMP were stable as a function of time and temperature in water. 27 So we have concluded that this behaviour was not caused by the breaking of ester links. Then two hypotheses can explain that.…”

Section: Swelling Behaviour Of the Gel Fractionmentioning

confidence: 88%

See 1 more Smart Citation

Metastable Amphiphilic Hydrogels Based on Crosslinked Carboxymethylpullulan

Legros

Cardinaël

Dulong

et al. 2008

Polym J

Self Cite

View full text Add to dashboard Cite

Section: Swelling Behaviour Of the Gel Fractionmentioning

confidence: 88%

“…27 The effect of temperature on hydrophobic associations has been discussed by some authors who worked on hydrophobically modified polymers. But they do not agree: most of them think that the temperature strengthens the hydrophobic interactions, 28,29 while others claim that it is the opposite.…”

Section: Swelling Behaviour Of the Gel Fractionmentioning

confidence: 99%

Metastable Amphiphilic Hydrogels Based on Crosslinked Carboxymethylpullulan

Legros

Cardinaël

Dulong

et al. 2008

Polym J

Self Cite

View full text Add to dashboard Cite

“…For higher degree of modification (z30% of octyl chains per anhydroglucose units), compact structure formed of isolated polymer chains has been identified due to intramolecular hydrophobic associations. We have shown that a competition between intramolecular and intermolecular associations could explain the metastability of the solution [14].…”

Section: Introductionmentioning

confidence: 90%

Adsorption of amphiphilic polysaccharides onto polystyrene latex particles

Simon

Picton

Cerf

et al. 2005

Polymer

View full text Add to dashboard Cite

“…The study of the gel fraction showed that it was metastable, evolving with time and temperature to reach a soluble state called infinite sol. This transition was not induced by a change in the crosslinking ratio or in the double grafting, so, by comparing with the behaviour of associative polymers, 21 we deduced that this transition was caused by an evolution of the hydrophobic interactions.In order to understand the double structure (chemical and physical) of our systems, we will study, in this paper, thanks to physicochemical measurements, the infinite sol of hydrogels issued of low molar masses carboxymethylpullulan. …”

mentioning

confidence: 86%

mentioning

confidence: 86%

Self-organization of Water Soluble and Amphiphile Crosslinked Carboxymethylpullulan

Legros

Dulong

Picton

et al. 2008

Polym J

Self Cite

View full text Add to dashboard Cite

The soluble state of amphiphile and crosslinked derivatives of carboxymethylpullulan was investigated by physicochemical analyses. This soluble state also called infinite sol was obtained from hydrogels after a short-time temperature treatment. The analyses show a large distribution in size for the species in solution (from some nanometers to some micrometers). Furthermore, they also reveal the presence of hydrophobic associations (intra and/or intermolecular) in addition to the chemical links. The nature of these hydrophobic interactions will depend on the polymer concentration and on the solvent used.KEY WORDS: Polysaccharide / Crosslinking / Hydrogels / Amphiphile / Self-organization / Hydrogels are suitable materials for drug delivery applications in biomedical and pharmaceutical fields. Indeed, active compounds can be easily entrapped and released, specially by responsive-stimuli devices which undergo phase transition or swelling-deswelling behaviour in response to environmental changes (temperature, pH, ionic strength, . . .). 1-3 Furthermore, they resemble natural living tissues by their ability to absorb and retain huge quantity of fluids and by their consistency, giving them a good biocompatibility. 4 Since several years, numerous studies have been interested in hydrogels based on polysaccharides and their derivatives because of their advantages over synthetic polymers. In fact, they are abundant, largely water soluble, biocompatible and descendent from renewable sources. 5 More recently, attention is focused on the development of amphiphilic networks able to transport amphiphilic and hydrophobic drugs. 6,7 Two majority ways are used to elaborate amphiphilic hydrogels based on polysaccharides. The most widespread way consists in grafting on the polymer backbone hydrophobic chains which self-aggregate in solution so creating cross-linking points but also hydrophobic domains. The most famous examples of this kind of systems are derivatives of pullulan bearing cholesteryl groups (CHP) which provide by self-aggregation particles able to complex hydrophobic molecules and proteins. [8][9][10][11][12][13] An other example consists of carboxymethylpullulan grafting by alkyl pendant groups. 14 The second technique consists in a chemical cross-linking with a hydrophobic agent. Few studies have been interested in this way although it gives in one step cross-links and amphiphilic character. So, Dulong et al. have elaborated amphiphilic carboxymethylpullulan networks using adipic dihydrazide 15 and N-hydroxysuccinimide, 16 whereas Coviello and Matricardi have choosen dibromohexan as cross-linking agent to obtain hydrogels from scleroglucan 17 and polygalacturonic acid. 18 We use the second method and dibromohexan to elaborate amphiphilic systems based on carboxymethylpullulan, an anionic derivative of pullulan (Figure 1). In a recent paper, 19 we showed that the cross-linking reaction was very fast, leading to creation of high crosslink density clusters as described by Hoffman. 20 On the other hand, we demonstrated ...

show abstract

Metastable state of amphiphilic polysaccharide solutions

Cited by 4 publications

References 17 publications

Metastable Amphiphilic Hydrogels Based on Crosslinked Carboxymethylpullulan

Metastable Amphiphilic Hydrogels Based on Crosslinked Carboxymethylpullulan

Adsorption of amphiphilic polysaccharides onto polystyrene latex particles

Self-organization of Water Soluble and Amphiphile Crosslinked Carboxymethylpullulan

Contact Info

Product

Resources

About