| Nanoliposomes as a carrier caused wide attention and research for its unique feature.Not only its phospholipids susceptible to be oxidized,easy integration gathered,these unstable factors making it easier to cause the drug leakage,but also lack of initiative targeting,so its application is restricted.Curcumin Extracted from curcuma,has a spectrum of biological activities.However,because of the poor solubility in water,sensitive to light,heat and other adverse environmental,its bioavailability is very low.Using liposome wrapped it up,the bioavailability of curcumin can be extently improved.In order to further improve the physical stability,sustained release and cellular uptake rate of liposomes,the main content of this study include make the small molecules of folic acid?fa?conjugated with chitosan?cs?,Folic acid-chitosan?fa-cs?coated on the surface of curcumin liposomes?lip-cur?by electrostatic interaction force.So the folic acid-chitosan coated liposomes?fa-lip-cur?was formed.Then investigate the differences of storage stability,slow-releasing potential and cellular uptake proporty between fa-lip-cur and lip-cur.Based on EDC and NHS as catalyst,folic acid-chitosan was synthesized.After infrared spectrum method is used to detect the functional groups of reaction product.According to the absorption peak of 1656 cm–1and 1606 cm-1,they represent the characteristic peak of chitosan and folic acid respectively.The results show that folic acid-chitosan was formed successfully.By thin film dispersion method combined with dynamic high pressure micro jet prepared nanoliposomes of curcumin?lip-cur?.The size of liposomes was 67.4±3.4 nm,zeta potential was-13.81±2.75 mv,and the particle size and zeta potential of fa-lip-cur were 103.6±4.1 nm and 16.35±3.54 mv respectively.The result of Slow release in vitro experiment show that fa-lip-cur show better slow release effect under alkalescent condition which compared with lip-cur.After 24h,the drug only release 17.7%from fa-lip-cur.Two kind of liposomes storage for 4 weeks under the condition of 25?,their particle size and zeta potential change weekly,but fa-lip-cur shows better protective drugs than lip-cur.At the same time,we investigate the affinity between fa-lip-cur/lip-cur and Caco-2.Determined by MTT colorimetric method,according to the results we can know that fa-lip-cur showed stronger cytotoxicity when under the high drug concentration?80?g/mL?,the cell survival rate is only 26%when dealed with fa-lip-cur,cell survival rate was 38%under lip-cur dispose.With the increase of drug concentration,the gap between the two kind of liposomes was further.Using inverted microscope to observe the cell morphology under different concentration of curcumin,with the increase of drug concentration,the number of cellular debris also increasing.By using the properties of fluorescigenic curcumin,with fluorescent inverted microscope to observe the fluorescence of Caco-2 which dealed with by fa-lip-cur and lip-cur respectively after 6 h.The group of fa-lip-cur showed stronger fluorescence.To sum up,folic acid-chitosan modified curcumin liposomes can improve the stability,slow-releasing potential and active targeting of liposomes in a certain extent.So it also further improve the utilization value of curcumin. |
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