Experimental Study On The Construction And Properties Of Chitosan Derivatives Nanoparticles

Objectives: The purpose of this study was to establish(Berberine)Ber nanoparticles prepared by ionic cross-linking and self-assembling method.In this sustained release drug delivery system,Ber was used as a model drug,while N-[(2-hydroxy-3-trimethylammonium)propyl] chitosan chloride(HTCC),N,O-carboxymethyl chitosan(NOCMS)and chitosan(CS)were used as carrier materials.The physicochemical properties of Ber nanoparticles such as morphology,diameter ect.were evaluated.Methods: The Ber nanoparticles with different drug/carrier ratio and different carrier material were prepared by ionic cross-linking and self-assembling method.The morphology and size were determined by Transmission electron microscope(TEM).The average diameters and polydispersity index were evaluated by dynamic light scattering(DLS).The interaction between various components and the nanocomplex were characterized by Fourier Transform Infrared Spectroscopy(FT-IR).The drug loading(DL),encapsulation efficiency(EE)and in vitro release were determined by UV/Vis spectrophotometer.Results: The results of TEM demonstrated that the Ber/HTCC nanoparticles were spherical in shape,uniform particle size and dispersed uniformly.The results of DLS showed that diameter and PDI of nanoparticles were 290.8 nm and 0.171,respectively.The average diameter and PDI were stable in 50 days which indicated the particles with uniform size and dispersion.The results of FT-IR showed that HTCC and TPP were eletrostatic binding and the characteristic peaks of Ber/HTCC nanoparticles confirmed that Ber was encapsulated in nanoparticles.The drug loading and encapsulation efficiency were 7.27~25.49 % and 88.37~96.87 %,respectively.The results of in vitro release study showed that the cumulative release of Ber from Ber/HTCC nanoparticles was 55.46 %~79.46 % in phosphate buffered saline(PBS,p H 7.4)within 48 h,which had sustained release effect.The results of TEM demonstrated that the Ber/NOCMS-CS nanoparticles were spherical with shrinkage blisters,uniform particle size and dispersed uniformly.The TEM showed that the diameter of Ber/NOCMS-CS nanoparticles was about 120 nm.The average diameter and PDI of nanoparticles were 300~350 nm and 0.2~0.3 respectively.The average diameter and PDI were stable in 50 days which indicated the particles with uniform size and dispersion.The results of FT-IR displayed that NOCMS and CS were eletrostatic binding and the characteristic peaks of Ber/NOCMS-CS nanoparticles confirmed the encapsulation of Ber.The drug loading and encapsulation efficiency were 11.04~33.30 % and 99.56~99.90 %,respectively.The results of in vitro release study showed that the release of Ber from Ber/NOCMS-CS nanoparticles was prolonged in PBS(p H 7.4),and a sustained release of 51.01 %~55.37 % within 48 h was observed.Conclusion: The Ber/HTCC and Ber/NOCMS-CS nanoparticles were prepared using ionic cross-linking and self-assembling method with good physical and chemical properties.The particles could used as a oral sustained release drug delivery system,which have regular spherical shape with a narrow distribution in diameter.The nanoparticles showed excellent stability in aqueous condition.Also,both of them can accommodate relatively large amount of Ber and the characteristics of sustained release.