Preparation And Antitumor Activity Of Co-assembly Of Curcumin And Doxorubicin Targeted Liposomes

Objective Colon cancer,as one of the malignant tumors that endanger human health in today’s society,has been paid more and more attention by more and more people.Modern medical treatment of colon cancer is mainly the use of chemical drugs to inhibit the tumor,but with the application of more and more chemical drugs,the tumor has a drug resistance,tumor treatment is becoming more and more difficult.Among many chemical drugs,Adriamycin has the most widely used anti-tumor spectrum,but there are also drug resistance problems in tumor treatment.With the continuous study of tumor by many scholars,the special microenvironment of tumor site has been found,and it has been found that the strong penetration and retention effect of tumor site will lead to poor therapeutic effect of chemotherapy drugs,therefore,the nanoparticle delivery system came into being.Nanoparticle delivery system is a good drug carrying strategy,which can stagnate at the tumor site and not be taken away by lymphatic circulation with the advantage of nano-particle micro-nano size.However,because it has only certain specificity and poor targeting effect,it will be a very effective drug delivery system if the specificity of the tumor site is reused to achieve the active targeting effect.The use of liposomes to carry Adriamycin to form Adriamycin liposomes,although it can improve the therapeutic effect of tumors to a certain extent,but because of the existence of multidrug resistance of tumors,the therapeutic effect is limited.Curcumin,as a traditional Chinese medicine in China,is also an edible pigment,with anti-inflammatory,anti-angiogenesis,anti-tumor and other pharmacological activities,with the deepening of modern research,it is found that curcumin also has the function of inhibiting P-glycoprotein.One of the important causes of multidrug resistance of tumor is the expression of P-glycoprotein,so curcumin is a potential multidrug resistance reversal agent.Methods Using liposomes as drug carriers and curcumin as chemotherapy sensitizer,Adriamycin was used as a chemotherapy drug to prepare the liposomes of double-loaded drugs,in order to achieve a more effective anti-tumor effect,the water solubility of curcumin was improved by the method of principal and object recognition.Theανβ3 specificity of cRGD peptide and the expression of tumor site was used to achieve the active targeting of liposomes.Results In this study,curcumin inclusions were first prepared.The method of Fourier infrared Spectroscopy and X-ray diffraction were used to characterize and verify curcumin encapsulation products.Secondly,the liposomes were prepared by thin film method,and the composition ratio of liposomes was optimized,and the optimum ratio of phospholipid and cholesterol to 5:1 was selected by comparing the particle size,PDI,encapsulation rate and dosage,and the particle size was 364.3±2.036nm,PDIas 0.194±0.059,the encapsulation rate is 94.95%,the dose is 1.36%liposomes.Then,FTIR and H-NMR were used to verify the synthesized DSPE-PEG2000-cRGD,and the cRGD-（CUR-CD+DOX）-LPs（2:1）liposomes were prepared by thin film method,and TEM was used to verify the appearance and morphology of liposomes,and the particle size meter was measured cRGD-（CUR-CD+DOX）The particle size of-LPs（2:1）was 379.5±4.950 nm,PDI as 0.192±0.01,zeta potential was-15.1±4.34 mV,the DOX charge was measured by high performance liquid chromatography was 0.15%,and the encapsulation rate was 71.28%.The dosage of CUR was 0.30%;The encapsulationrateis50.8%.Finally,theinhibitoryeffectof cRGD-（CUR-CD+DOX）-LPs（2:1）on tumor cells was studied.The average fluorescence intensity of intracellular swallowing was detected by flow cytometry,and the fluorescence intensity was observed by fluorescence inverted microscope,and the density of the optimum cRGD peptide on the surface of liposomes was 9.56%.The toxicity of the cells was investigated by MTT method,and the results showed that the tumor growth could be inhibited obviously compared with adriamycin hydrochloric acid saline solution（DOX-sol）.In order to study the way of swallowing,the fluorescence intensity was detected by flow cytometry,and it was concluded that the way for liposomes to enter the cells was through the internal swallowing pathway,the way of small nest protein mediated and the method mediated by non-mesh protein and small nest protein.The internal swallowing of various preparations in cells was detected by fluorescence microscope,laser confocal scanning microscope and flow cytometry,and the results showed that cRGD-（CUR-CD+DOX）-LPs（2:1）had the strongest red fluorescence DOX after treatment of cells,and had the best effect.Study of cRGD-（CUR-CD+DOX）-LPs（2:1）in the results of cell cycle,cRGD-（CUR-CD+DOX）-LPs（2:1）can block HCT-8/TAX cells in the G₂/M period of mitosis,It has obvious effect on apoptosis in the results of apoptosis-inducing apoptosis.Conclusion DOX and CUR-CD were loaded into liposomes and targeted to group cRGD on surface modification,and cRGD-（CUR-CD+DOX）-LPs（2:1）was obtained.The results of cell experiments show that the liposomes,in addition to showing good anti-tumor effect on HCT-8/TAX cells,also have a certain effect of reversing multidrug resistance,which provides an effective experimental basis for the development and improvement of nano-particle delivery system of colon cancer.