Preparation And Drug-loading Properties Of Novel Drug Carriers

Drug carriers can improve the utilization rate and safety of the drug,reduce the frequency of administration,improve the unpleasant odor of the drug.It also can improve the accuracy of the administration dosage and the accurate release of the drug to the targeted tissues and organs.Therefore,drug carriers have received extensive attention.The development of nanotechnology has promoted the research of drug carriers.The research and application of nano-scale drug carriers have made great contributions in the medicine field.In this paper,carboxymethyl chitosan(CMC),hydroxypropyl chitosan(HPC),β-cyclodextrin(β-CD),hydroxypropyl-β cyclodextrin(HP-β-CD)and Lysine(Lyc)were used to prepare nanohydrogels.Lyc-CMC-g-β-CD nanohydrogels and HPC-g-HP-β-CD nanohydrogels were prepared separately and used as drug carriers.The paper used 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride(EDC)and N-hydroxysuccinimide(NHS)to promote condensation reaction.We characterized the morphology,molecular weight,particle size,and pH responsiveness of the prepared nanohydrogels.The performance of the two different nanohydrogels were explored through the degradation experiments in vitro,drug-loading and drug-releasing experiments,and cytotoxic experiments.The results showed that the two prepared nanohydrogels were suitable as drug carriers.There were carboxyl groups and amino groups on the surface of the prepared Lyc-CMC-g-β-CD nanohydrogels.β-CD was modified with succinic anhydride(Suc).Fourier infrared Spectroscopy and Mass Spectrometry were used to analyze the structure changes of products.The results showed that Suc-β-CD was successfully prepared.Suc-β-CD was grafted onto CMC to obtain a copolymer,then Lyc was grafted onto the copolymer.Fourier infrared Spectroscopy and GPC were used to characterize structure changes of the copolymer.Lyc-CMC-g-β-CD was successfully prepared.We used SEM,TEM and AFM to analyze the morphology of copolymers and nanohydrogels.We analyzed the particle size changes of Lyc-CMC-g-β-CD at different pH values by Zeta potential analyzer,and conducted potential analysis of the nanohydrogels,which with an isoelectric point between pH 6-7.The nanohydrogels have a small size(150 nm)and are stable in an acidic environment.There are hydroxyl groups and amino groups on the surface of HPC-g-HP-β-CD nanohydrogels.HP-β-CD was modified with maleic anhydride(Mah)and grafted onto HPC.Mah-HP-β-CD was successfully synthesized after infrared and nuclear magnetic analysis,and HPC-g-HP-β-CD was successfully prepared by infrared,nuclear magnetic and GPC analysis.Through SEM,TEM and AFM test,the morphological characteristics of the nanohydrogels were analyzed.The particle size and Zeta potential at different pH values were analyzed using a Zeta analyzer.It showed that the particle size of the prepared nanohydrogels was about 110 nm,the size has changed in different pH environments,and the isoelectric point was between pH 7-8.Lyc-CMC-g-β-CD nanohydrogels and HPC-g-HP-β-CD nanohydrogels did degradation experiments,drug-loading and cytotoxicity experiments respectively.The results showed that the nanohydrogels prepared by us had good degradation rate.Lyc-CMC-g-β-CD nanohydrogels could be completely degraded in 12 days.HPC-g-HP-β-CD nanohydrogels could be degraded in 12 days.The two hydrogels had strong drug-loading and drug-releasing capabilities and were suitable as drug carriers of berberine hydrochloride and ibuprofen.The MTT test showed that the prepared nanohydrogels were nontoxic to normal cells and were beneficial to cell growth.We can determine that the prepared Lyc-CMC-g-β-CD and HPC-g-HP-β-CD nanohydrogels are suitable as drug carriers.