The Preparation Of Starch Nanoparticles By Nanoprecipitation And Their Loads Characteristic For Active Ingredients

Starch nanoparticles (SNPs) were prepared by anti-solvent precipitation using fractionated amylose and amylopectin from potato starch, maltodextrin, and short-chain amylose. The morphology, size distribution, molecular weight, crystal structure, and thermal properties of SNPs prepared with different volume ratio of starch solution to absolute ethanol were investigated by transmission electron microscopy (TEM), dynamic light scattering (DLS), high-performance size-exclusion chromatography, X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis, and Fourier transform infrared spectroscopy analysis (FTIR). Furthermore, the properties of the active ingredient loaded SNPs were also investigated. Main conclusions were as follows:1. For the first time, we have successfully prepared worm-like amylopectin nanoparticles (APNPs) and spherical amylose nanoparticles (AMNPs) using fractionated amylose and amylopectin from potato starch. Polyphenols are known to have potent antioxidant capacity and other health-beneficial bioactivities. However, extremely low absorption rate of polyphenols restricts their bioactivity in vivo. Development of biopolymer nanoparticle carrier is a promising solution. Additionally, adsorption kinetics and adsorption isotherms of three polyphenols (procyanidins, epicatechins and catechins) on AMNPs and APNPs were investigated. We found that procyanidins, epicatechins, and catechins could bind to AMNPs at levels of up to 1.2,1.5, and 1.4 g/g, respectively, while the APNPs demonstrated higher adsorption amounts of 1.4,4.3, and 2.2 g/g, respectively. Furthermore, the particle size of polyphenol-loaded nanoparticles was not significantly changed. The results suggested that APNPs and AMNPs can be applied as an effective nanocarrier by delivering active compounds for neutracutical and pharmaceutical industries.2. For the first time, we have successfully prepared maltodextrin nanoparticles (MNPs) with controllable particle sizes. The influence of different emulsifier types and volume ratios of maltodextrin solution to absolute ethanol on morphology, size and structure of MNPs was examined. The smallest MNPs (30-90 nm) were obtained when the volume ratios was 1:10 and the emulsifier was Tween 80. Active polysaccharides are known to have a wide variety of biological functions, such as immune regulation, anti-viral, anti-oxidant, and anti-tumor effects, hypoglycemic and lipid-lowering effects. However, extremely low oral bioavailability of polysaccharides restricts their bioactivity in vivo. Development of biopolymer nanoparticle carrier is a promising solution. Furthermore, tea, pumpkin, balsam pear polysaccharides were loaded on MNPs with loading efficiency of 63.5,68.7,72.1%, respectively. Compared with the MNPs, the polysaccharides-loaded MNPs were more stable in high salt content, or under gastric pH 1.2 and physiological pH 7.4 conditions. The MNPs may serve as an effective nanocarrier by delivering active polysaccharides to enhance its bioavailability.3. Starch nanoparticles (SNPs) with controllable particle sizes were prepared by anti-solvent precipitation using short-chain amylose. The morphology, size distribution, molecular weight, crystal structure, and thermal properties of SNPs prepared with different volume ratio of starch solution to absolute ethanol were investigated by transmission electron microscopy, dynamic light scattering, high-performance size-exclusion chromatography, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and Fourier transform infrared spectroscopy analysis. When the volume ratio of starch solution to absolute ethanol was 1:4, the SNPs had the smallest particle size (20-100 nm). All SNP samples displayed a typical V+A-type crystalline structure and had a high relative crystallinity (42.3-48.6%). Compared with native waxy corn starch, the gelatinization temperature of SNPs was higher and the temperature range was broader. Moreover, the oxidative stability and effective time of essential oil was extended by its encapsulation in short-chain amylose nanoparticles.