Optimal Concentration Of Chitosan Research Articles

Effect of concentration and molecular weight of chitosan and its derivative on the free radical scavenging ability

Chitosan is a biodegradable and biocompatible natural scaffold material, which has numerous applications in biomedical sciences. In this study, the in vitro antioxidant activity of chitosan scaffold material was investigated by the chemiluminescence signal generated from the hydroxyl radical (•OH) scavenging assay. The scavenging mechanism was also discussed. The results indicated that the free radical scavenging ability of chitosan scaffold material significantly depends on the chitosan concentration and shows interesting kinetic change. Within the experimental concentration range, the optimal concentration of chitosan was 0.2 mg/mL. The molecular weight of chitosan also attributed to the free radical scavenging ability. Comparison between chitosan and its derivative found that carboxymethyl chitosan possessed higher scavenging ability.

Utilization of biopolymer in resist printing of linen fabrics using reactive dyes

A novel utilization of chitosan as a cationic biopolymer in the chemical resist printing of linen fabrics and its polyester blend using reactive dyes. The effects of ratio and concentration of various resist-printing agents and processing conditions are observed and discussed. The concentration of chitosan, type of resist agent, and the ratio of chitosan to resist agent were varied to determine their effects on the efficiency of resist-printing. Regardless of the type of fabric, the resist effect on printed fabrics expressed as % decrease in K/S was obtained at optimal chitosan concentration of 1% with a mixture of chitosan/maleic acid as a resist salt at a ratio of 25:75. Thus, chitosan can be used pure or in admixture with different resist salts successfully in chemical resist printing.

Pretreatment of Cheese Whey Effluent Using a Microfiltration Process: A Statistical Design Approach

Pretreatment of cheese whey effluent from the dairy industry using chitosan as a coagulant and a microfiltration process such as a solid/liquid separator was investigated in this study. The optimization of major process variables, such as chitosan concentration, transmembrane pressure, and operation time on permeate flux and COD removal efficiency was investigated. To find the most appropriate result for the experiment, The Box–Wilson experimental design was employed. Response function coefficients were determined by regression analysis of experimental data and predictions were found to be in good agreement with the experimental results. The optimal concentration of chitosan and transmembrane pressure was 5 mg/L and 2 bar pressure for maximum permeate flux with a 23.0 L/m2.h flux value, respectively. On the

Effect of absorption enhancers on nasal delivery of basic fibroblast growth factor

The present study was to screen an optimal absorption enhancer for enhancing the nasal absorption of basic fibroblast growth factor (bFGF), a promising therapeutic agent to neurodegenerative diseases. In this study, four absorption enhancers including chitosan, sodium caprate, poly-L-arginine (poly-L-Arg, 92.0 kDa) and dimethyl-β-cyclodextrin were chosen to evaluate their toxicity using in situ toad palate model and in vitro Calu-3 cell model. Transport study of bFGF across Calu-3 cell monolayers in the absence or presence of chitosan was performed to determine the optimal concentration of chitosan. Pharmacokinetics study was conducted to monitor changes in the blood concentration of bFGF following nasal administration of bFGF solution with or without 0.5% (w/v) chitoson, in comparison with intravenous administration of bFGF alone. Of the absorption enhancers tested, chitosan at the concentration of 0.25 and 0.5% showed little toxicity to nasal cilia and Calu-3 cells, and exerted reversible effect on the reduction of transepithelial electrical resistance. Transport study showed that the apparent permeability coefficient (Papp) value was increased by about 16- and 2-fold, respectively with addition of 0.5 and 0.25% chitosan, compared with bFGF solution alone. Following nasal administration to rats, the formulation containing 0.5% chitosan significantly enhanced the absorption of bFGF with an area under curve (AUC0-120min) nearly 1.4-fold that of bFGF solution (p<0.05). The absolute bioavailability of bFGF after intranasal administration was 5.35 and 7.53% for bFGF alone and 0.5% chitosan group, respectively. These results indicated that 0.5% chitosan is a safe and effective absorption enhancer for intranasal delivery of bFGF. Key words: Basic fibroblast growth factor, absorption enhancer, chitosan, toxicity, pharmacokinetics, intranasal delivery.

Effect of chitosan on resist printing of cotton fabrics with reactive dyes

The concentration of chitosan, types of resist agent, curing temperature and curing time were varied to determine their effects on resist-printed cotton fabrics. An optimal chitosan concentration of 1.6% resulted in the greatest resist effect on printed cotton fabrics. For mixtures, a 6:4 ratio of citric acid : chitosan and an 8:2 mixture of tartaric acid : chitosan yielded the greatest resist effects. A curing temperature of 150°C for 180 s was optimal. Key words : Chitosan, resist printing, reactive dyes, cotton fabrics.

A ZnO/Chitosan Composite Film: Fabrication and Anticorrosion Characterization

A composite film consisting of ZnO and Chitosan (CS) is obtained on carbon steel via cathodic electrodeposition. Optimal CS concentration of electrodeposition of ZnO/CS film is determined by the method of polarization curves. It is shown that the ZnO/CS film obtained at the concentration of 0.6 g/L has the best corrosion resistance. The deposit is studied by scanning electron microscopy (SEM), Fourier transform infrared spectra (FT-IR) and X-ray diffraction (XRD). XRD results indicate that ZnO could be fabricated by electrodeposition in composite film. FT-IR results evidence the existence of CS in composite film. SEM results demonstrate that the quality of film is improved because of the addition of CS. The anticorrosion property can be attributed to that the existence of the CS macromolecules can improve the stability of the composite film. This kind of composite film has an anticorrosion application for metal corrosion protection.

Chitosan as green kinetic inhibitors for gas hydrate formation

The kinetic inhibiting effect of a number of chitosans on hydrate formation was investigated using methane and methane/ethane gas mixtures. The results indicated that chitosan was a good kinetic inhibitor. The induction time of gas hydrate formation evidently increased with the degree of deacetylation (DD), however, when DD was higher than 80%, the effect of DD on the induction time was negligible. Moreover, it was found that the molecular weight (MW) of chitosan and the addition of polyethylene oxide (PEO) had little effect on the induction time. The optimal concentration of chitosan was found to be 0.6 wt%. Finally, the mechanisms of the kinetic inhibitor on the hydrate formation were discussed.

Flocculation of algae using chitosan

Flocculation of three freshwater algae, Spirulina,Oscillatoria and Chlorella, and onebrackish alga, Synechocystis, using chitosan was studiedinthe pH range 4 to 9, and chlorophyll-a concentrations inthe range 80 to 800 mg m−3, which produces aturbidity of 10 to 100 nephelometric turbidity units (NTU) in water. Chitosanreduced the algal content effectively by flocculation and settling. Theflocculation efficiency is very sensitive to pH, and reached a maximum at pH7.0for the freshwater species, but lower for the marine species. The optimalchitosan concentration that is required to effect maximum flocculation dependedon the concentration of alga. Flocculation and settling were faster whenconcentrations of chitosan higher than optimal are used. The settled algalcellsare intact and live, but will not be redispersed by mechanical agitation. Thede-algated water may be reused to produce fresh cultures of algae.

Flocculation of river silt using chitosan

Flocculation of silt in river water using chitosan was studied in the pH range 4–9, and suspended solid concentrations in the range 20–80 mg/L. Chitosan effectively reduces turbidity due to silt by flocculation and settling. Flocculation efficiency is very sensitive to pH, and reaches a maximum at pH 7. The optimal chitosan concentration required to effect flocculation is 0.5 mg/L and is independent of silt concentration within the range examined. Restabilisation of the suspension is observed at higher concentrations of chitosan, and the amount required for restabilisation increases with increasing concentration of suspended solids. Flocculation is faster at higher concentrations of silt and the flocs are large and fibrous.

Flocculation of kaolinite suspensions in water by chitosan

Flocculation of kaolinite suspensions in water using chitosan was studied in the pH range 5–9 and the turbidity ranging from 10 to 160 NTU. Chitosan, in presence of trace quantities of a substance present in aqueous soil extracts, effectively reduces turbidity due to kaolinite by flocculation and settling. Flocculation efficiency is very sensitive to pH, and reaches a maximum at pH 7.5. The optimal chitosan concentration required to effect flocculation is independent of kaolinite concentration within the range examined. Flocculation is faster at higher concentrations of kaolinite and the flocs are large and settle rapidly.