Loading...
Please wait, while we are loading the content...
Similar Documents
Title Epigallocatechin Gallate Loaded Chitosan Nanoparticles
| Content Provider | Semantic Scholar |
|---|---|
| Copyright Year | 2008 |
| Abstract | The main objectives of this study were to study the factors which effect on the preparation of epigallocatechin gallate (EGCG) nanoparticles and investigate the physicochemical properties of the prepared CS nanoparticles. Nanoparticles were prepared by methods based on ionotropic complexation between chitosan (CS) and sodium carboxymethylcellulose (SCMC). Various factors influencing in nanoparticles preparation, such as concentration, pH, ratio of the polymers, mixing duration and amount of EGCG, were systematically optimized by evaluating size, size distribution, surface charge and entrapment efficiency of the prepared nanoparticles. The EGCG release profiles at pH 1.2, 6.8 and 7.4 and the stability of EGCG in the nanoparticles at -20 C, 30 C and 40 C were further examined by HPLC-UV. The antioxidant activity of EGCG in nanoparticles and compared with the extract was investigated by 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method and ferric reducing/antioxidant power (FRAP) methods. The best nanoparticulate system showed the average smallest size of 228.25 + 7.47 nanometer with narrow range of size distribution (0.28 + 0.03) and high loading efficiency v (98.04 +0.60%). Maximal EGCG loading was obtained by adding the appropriate amount of SCMC into the EGCG containing CS solution. The suitable condition was 0.1% CS (pH 3) solution and 1% SCMC with the mixing ratio between CS and SMCC was 1:1. Morphology of the nanoparticles inquired by transmission electron microscopy (TEM) demonstrated that the nanoparticles with and without EGCG extract were of spherical shape. The release study indicated an initial burst release of EGCG extract from the nanoparticles after 15 min in a medium, pH 1.2. Sustained and limit release of EGCG was observed at the higher pHs. This was due to high extent of EGCG degradation at neutral and basic pHs. However, at different storage temperatures, the stability of EGCG could be preserved in the nanoparticles compared with the untrapped EGCG. Antioxidant activity of EGCG analysis by ABTS and FRAP methods showed that the trolox equivalent antioxidant capacity (TEAC) value EGCG nanoparticles suspension was 54.96 + 4.46. mmol/mg and the equivalent concentration as the concentration of antioxidant having a ferric-TPTZ reducing ability equivalent to that of a the concentration of FeSO4 7H2O (EC1) was 8.96 + 0.62 mmol/mg, respectively. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://repository.cmu.ac.th/bitstream/6653943832/31014/2/phars0807bs_abs.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
