Oral drug-loaded nano-system include nano-gel drug delivery system, nano-suspension drug delivery system, nano-particle drug delivery system, liposomes drug delivery system, nano-micelles drug delivery system, alcohol liposoms,nano-framework drug delivery system, nano-emulsions drug delivery system, nano-self assembly drug delivery system.These nano-drug delivery systems can serve as multi-functional drug carriers.They may significantly improve the physicochemical and stabilization and biological properties of the free drug, enhance the therapeutic efficiency and reduce toxic side effects.This paper reviews the recent research progress in oral drug-loaded nano-systems.

Objective To investigate the physicochemica l properties and immunobiological activity of a polysaccharide (RAP-B-1) from stems of Rubus amabilis. Methods The crude polysaccharide (RAP) was obtained successively by boiling, ethanol precipitating and dialyzing. RAP was isolated with DEAE-cellulose and Sephadex G-100 to obtain a polysaccharide RAP-B-1. The physicochemical properties of RAP-B-1 were studied by hydrolysis, periodate oxidation, Smith degradation and methylation, CE, IR, NMR and GC-MS. The immunobiological activities were estimated by the proliferative activity of spleen lymphocytes and phagocytic activity of peritoneal macrophages in mice. Results The molecular weight of RAP-B-1 was 4.80×104 with specific optical rotation value [α] 20D+68.3 (c=1,H2O), and was composed of eight monosaccharides. The molar ratios were as Xyl: Ara: Glc: Rha:Gal: Man: GlcA: GalA = 1.0:6.9:0.8:1.1:6.9:0.3:0.5:3.3. RAP-B-1 was an arabinogalactan. The linkages of arabinose were →1) Ara (2,3→,→1) Ara(5→and→1) Ara, and the linkages of galactose were→1) Gal(4→,→1) Gal(6→and→1) Gal. RAP-B-1 could improve the proliferative activity of spleen T cells(P<0.05) and booste phagocytic activity of peritoneal macrophages at 50μg/ml concentration(P<0.01). Conclusion RAP-B-1 is an arabinogalactan and has immunobiological activity.