Synthesis and characterisation of chemically modified chitosan microspheres

Shantha, K. L.; Harding, D. R.

doi:10.1016/s0144-8617(01)00244-2

Cited by 92 publications

(29 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Secondly, a wide variation in glass transition temperature may be observed due to the source and/or method of extraction. Generally the minimum and maximum glass transition temperature of chitosan are −23 ∘ C and 203 ∘ C, respectively [31,32], and the decomposition temperature of chitosan was found 295 ∘ C [34].…”

Section: Thermal Stability Of Cht-mc Compositesmentioning

confidence: 98%

Facile Preparation of Biocomposite from Prawn Shell Derived Chitosan and Kaolinite-Rich Locally Available Clay

Biswas

Rashid

Mallik

et al. 2017

International Journal of Polymer Science

View full text Add to dashboard Cite

A novel composite material was prepared from prawn shell derived chitosan (CHT) and locally available kaolinite-rich modified Bijoypur clay (MC) using a facile technique in which dilute acetic acid was used as a solvent for dissolving chitosan and composite fabrication whereas distilled water was used for preparing the clay dispersion. Bijoypur clay mainly consists of kaolinite clay mineral and it was modified with the dodecyl amine to make it organophilic. Morphology and properties of the composites (different weight ratio of MC and CHT) have been studied and compared with those of pure CHT and MC. Purification and modification of Bijoypur clay were investigated by X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier transformed infrared spectroscopy (FTIR) analyses. The fabrication of CHT-MC composites was confirmed by FTIR analysis. Thermogravimetric analysis (TGA) and differential scanning colorimetry (DSC) were used to investigate the thermal stability of the composites. It was observed that dispersed clay improves the thermal stability and enhances the hardness of the matrix systematically with the increase of clay loading. In this study, a better insolubility in both acidic and alkaline media of the composites is also observed compared to pure chitosan.

show abstract

Section: Thermal Stability Of Cht-mc Compositesmentioning

confidence: 98%

Facile Preparation of Biocomposite from Prawn Shell Derived Chitosan and Kaolinite-Rich Locally Available Clay

Biswas

Rashid

Mallik

et al. 2017

International Journal of Polymer Science

View full text Add to dashboard Cite

show abstract

“…This could be attributed to a steric effect caused by the presence of PEG, which might hinder the interaction with TPP, thus making necessary the use of higher amounts of the crosslinker. 30 The effects of (i) CS PEGylation degree, (ii) pH of the CS-g-PEG polymer solution and (iii) CS-g-PEG/TPP ratio on the size and polydispersity of the nanoparticles is shown in Figures 1(A) and (B). It can be noted that CS-g-PEG/TPP nanoparticles can be easily prepared over a relatively wide range of experimental conditions, being the pH of the initial CS-g-PEG solution the most important parameter influencing the size of the nanoparticles.…”

Section: Preparation Conditions and Physicochemical Characteristics Omentioning

confidence: 99%

Ionically Crosslinked Chitosan Nanoparticles as Gene Delivery Systems: Effect of PEGylation Degree on <I>In Vitro</I> and <I>In Vivo</I> Gene Transfer

Csaba

Köping-Höggård²,

Fernández-Megía³

et al. 2009

Journal of Biomedical Nanotechnology

View full text Add to dashboard Cite

The purpose of this work was to develop a new type of nanoparticles made of PEG-grafted chitosans (CS-g-PEG) using tripolyphosphate (TPP) as a polyanionic crosslinker and to investigate the potential of these nanostructures as gene carriers. The formation of these nanoparticles was optimised by the evaluation of the combined effects of pH, PEGylation degree and chitosan/crosslinker ratio on the particle formation. The selected CS-g-PEG/TPP nanoparticles were studied with regard to their physico-chemical properties, DNA association efficiency as well as to their toxicity and gene expression in vitro. Furthermore, the best performing nanoparticle prototypes were also evaluated for their potential for in vivo gene delivery. CS-g-PEG/TPP nanoparticles displayed a high DNA association efficiency combined with high stability and low cellular toxicity. The results of the in vitro transfection assays showed positive effects of the PEGylation in the case of particles prepared from high molecular weight chitosan, while the presence of PEG slightly decreased the efficiency of the nanoparticles based on low molecular weight chitosan. Overall, high and long lasting gene expression levels could be observed for all types of nanoparticles. Moreover, CS-g-PEG/TPP nanoparticles also mediated high gene expression levels in vivo, following nasal administration. These results indicate the potential of ionically crosslinked CS-g-PEG/TPP nanoparticles as transmucosal gene delivery systems.

show abstract

“…Other strong transitions were found at 266, 307 and 345 1C, and this may be due to the faster decomposition of the microspheres. And chitosan microspheres show strong transitions at 200 1C [8]. The reason for this phenomenon may be because of the crosslinking of artemisia seed gum and chitosan.…”

Section: Magnetic Propertiesmentioning

confidence: 99%