Polylactide-based microspheres prepared using solid-state copolymerized chitosan and d , l -lactide

Демина, Т. С.; Акопова, Т. А.; Vladimirov, L. V.; Зеленецкий, А. Н.; Марквичева, Елена; Grandfils, Ch.

doi:10.1016/j.msec.2015.09.094

Cited by 37 publications

(25 citation statements)

References 25 publications

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“…Compared to our former study where chitosan copolymers made of short grafted oligo( d,l ‐lactide) sequences (DP from 3 to 10) were water dispersible, polyester sequences with DP >10 reduce drastically their affinity to aqueous medium. Therefore, we have limited our solubility study to organic medium only.…”

Section: Resultscontrasting

confidence: 68%

“…Compared to data previously reported in ref. where copolymers made from chitosan with shorter grafted oligolactide chains (DP≤10) were mixed with PDLA, the microencapsulation yield was increased from 22 ± 1 to 74 ± 2 wt%, when the DP of polyester chain was raised from 3 to 10.…”

Section: Resultsmentioning

confidence: 99%

“…In a complementary experiment, we decided to assess the miscibility and interfacial activity of the more efficient grafted copolymer, that is, CDL‐I, with either high‐molecular‐weight polyesters (PLLA or PDLA), or either with oligo( l,l ‐lactide) or oligo( d,l ‐lactide). For the sake of comparison with our former experiments, the copolymers were mixed with the homopolyesters in a 30/70 wt ratio and without adding any surfactant in the aqueous phase of the emulsion. The evolution of microsphere yield and size distribution given on Figure clearly highlight that the optimal formulation conditions corresponds to the CDL‐I−PDLA blend.…”

Section: Resultsmentioning

confidence: 99%

“…In particular, we have played on the length and stereochemical composition of the hydrophobic grafted fragments. The proof of concept of this approach has been already demonstrated in one of our former study, using chitosan with short graft moieties of oligo( d,l ‐lactide) (degree of polymerization (DP) ≤10) . These copolymers could be directly dissolved as a biodegradable emulsifier excipient in oil phase, avoiding therefore the presence of any additional emulsifier in the aqueous phase of the emulsion during microparticle preparation.…”

Section: Introductionmentioning

confidence: 96%

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Chitosan‐g‐Polyester Microspheres: Effect of Length and Composition of Grafted Chains

Демина

Sevrin

Kapchiekue

et al. 2019

Macro Materials & Eng

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Hydrophobic segments made of oligo(l,l‐ or d,l‐lactides) or poly(l,l‐lactide) are grafted onto chitosan backbone in order to use their amphiphilic behavior to prepare degradable microcarriers intended to be used for tissue engineering. Hydrophilic–lipophilic balance of these copolymers is adjusted playing on the respective length of their hydrophilic and hydrophobic moieties. Thanks to their self‐emulsifying properties, these graft copolymers are processed into microspheres in the absence of hydrophilic emulsifier commonly added in the aqueous phase of the oil/water emulsion. The copolymers containing amorphous oligolactide segments of medium length are demonstrated to be the most effective ones for microparticle fabrication. The microparticles are characterized using SEM, EDX, and FTIR. The reactivity of amine group is demonstrated using fluorescein isothiocyanate staining. The resulting microspheres disclose a porous core and a shell enriched by the hydrophilic polysaccharide moieties. Stabilization of the oil/water interface during the microsphere fabrication, total yield, size distribution, and microparticle surface morphology are mainly affected by the macromolecular features of the copolymers.

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Section: Resultscontrasting

confidence: 68%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 96%

See 2 more Smart Citations

Chitosan‐g‐Polyester Microspheres: Effect of Length and Composition of Grafted Chains

Демина

Sevrin

Kapchiekue

et al. 2019

Macro Materials & Eng

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“…In recent times, such equipment was mainly used for processing pastes in the preparation of additives. However, the possibilities of the solvent-free extrusion method for conducting solid-state organic reactions has gained more attention in more recent days [19][20][21][22]. In this way, extrusion processes performing the derivatizing and grafting of polysaccharides are very interesting, as they require the activation of their functional groups stacked within the native highly organized supramolecular structures.…”

Section: Introductionmentioning

confidence: 99%

Solid-State Synthesis of Water-Soluble Chitosan-g-Hydroxyethyl Cellulose Copolymers

et al. 2020

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Graft copolymers of chitosan with cellulose ether have been obtained by the solid-state reactive mixing of chitin, sodium hydroxide and hydroxyethyl cellulose under shear deformation in a pilot twin-screw extruder. The structure and composition of the products were determined by elemental analysis and IR spectroscopy. The physicochemical properties of aqueous solutions of copolymers were studied as a function of the composition, and were correlated to the mechanical characteristics of the resulting films to assess the performance of new copolymers as coating materials, non-woven fibrous materials or emulsifiers for interface stabilization during the microparticle fabrication process.

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Macroporous hydrogels based on chitosan derivatives: Preparation, characterization, and in vitro evaluation

Демина

Zaytseva-Zotova

Акопова

et al. 2016

J of Applied Polymer Sci

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Chitosan-based hydrogels are considered as promising biomaterials for tissue engineering. Biological properties of chitosan could be significantly improved by modification of its chemical structure. This study was aimed at characterizing macroporous hydrogels fabricated by freeze-drying technique from chitosan, which has been N-acetylated by 2,2-bis(hydroxymethyl)propionic acid or L,D-lactide. The nature of the acetylated agent was shown to significantly affect hydrogels morphology, swelling behavior, zetapotential, and protein sorption as well as their degradation by lysozyme. According to scanning electron and confocal laser scanning microscopy, the hydrogels possessed interconnected macroporous network that facilitated cells penetration into the interior regions of the hydrogel. Chemical modification of chitosan significantly influenced L929 cell growth behavior on hydrogel compared to the nonmodified chitosan. The proposed chemical strategy for modification of chitosan could be considered as promising approach for improvement of chitosan hydrogels.

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Polylactide-based microspheres prepared using solid-state copolymerized chitosan and d , l -lactide

Cited by 37 publications

References 25 publications

Chitosan‐g‐Polyester Microspheres: Effect of Length and Composition of Grafted Chains

Chitosan‐g‐Polyester Microspheres: Effect of Length and Composition of Grafted Chains

Solid-State Synthesis of Water-Soluble Chitosan-g-Hydroxyethyl Cellulose Copolymers

Macroporous hydrogels based on chitosan derivatives: Preparation, characterization, and in vitro evaluation

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