18A-2 |
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H. J. PARK, Graduate School of Biotechnology, Korea Univ., Seoul, 136-701, South Korea and J. J. Song, Environmental Engineering, Mokpo University, Chunggae, Muan, Mokpo, South Korea. Linoleic acid (LA) chitosan nanoparticles were prepared by O/W emulsification method with methylene chloride, which can be used to encapsulate lipid soluble compounds. Methylene chloride was used as oil phase which is not suitable for the preparation of nanoparticles which act as a protein delivery carrier. However, nanoparticles preparation using LA-chitosan by self-aggregation in the aqueous solution and in the absence of methylene chloride need to be studied. The objective of our study was to prepare and characterize the self-assemblied nanoparticles using hydrophobic chitosan and its feasibility as a delivery carrier for proteins. Chitosan was modified by coupling with linolenic acid through the 1-ethyl-3-(3-dimethylaminopropyyl) carbodiimide (EDC)-mediated reaction. The degree of substitution was measured by 1H NMR and it was 1.8% which translates to 1.8 linolenic acid group per 100 anhydroglucose units. The critical aggregation concentration (CAC) of the self-aggregate of hydrophobically modified chitosan was determined by measuring the fluorescence intensity of the pyrene as a fluorescent probe. The CAC value in phosphate- buffered saline (PBS) solution (pH 7.4) was 0.05 mg/mL. The average particle size of self-aggregates of hydrophobically modified chitosan in PBS solution (pH 7.4) was 210.8 nm with a unimodal size distribution ranging from 100-500nm. Transmission electron microscopy (TEM) study showed formation of near spherical shape nanoparticles having enough structural integrity. The loading ability of hydrophibically modified chitosan (LA-chitosan) was investigated by using bovine serum albumin (BSA) as a model protein.Self-aggregated nanoparticles exhibited increased loading capacity (19.85 to 37.57 %) with increasing concentration of BSA (0.1 to 0.5mg/ml). Nanoparticles were of small in size (mean dia. of ca. 210.8 nm) with a unimodal size distribution. The LA-chitosan nanoparticles system was observed as a host for water-soluble proteins such as BSA indicated that it is also a good carrier for proteins delivery.
Session 18A, Carbohydrate: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |