Metal Halide Ion Regulation Of Interaction Between Nanogold And Liposome

As the carrier of anti-tumor drugs,liposomes can not only reduce the toxic and side effects of chemotherapy drugs,but also improve the targeting of drugs on tumors,thus improving the anti-cancer activity and the cure rate of patients.Therefore,they have attracted the attention of domestic and foreign experts.Liposomes can encapsulate drugs,provide biocompatible interfaces and serve as models for cell membranes,while inorganic nanomaterials have optical,electrical,magnetic and catalytic properties.Therefore,their hybrid systems are expected to be used for drug delivery,imaging and biosensing.Liposomes can be attached to the surface of inorganic nanomaterials by covalent bonds or specific biological interactions or by simple physical adsorption.It has been shown that choline amphoterophosphate liposomes(PC)interact with gold nanoparticles through van der Waals force,which is a short-range interaction and rapidly decays with the increase of the distance between particles.Here,we confirm that halogen ions can regulate the interaction between nano-gold and liposomes in a very small size,leading to different degrees of phase transition of liposomes and further leading to different degrees of leakage of contents.At the same time,liposomes can regulate the optical properties of nano-gold,resulting in a certain absorption peak of the hybrid system at 808 nm.Therefore,the hybrid system can be used for photothermal treatment of tumors.The main contents and conclusions of this paper are divided into the following three parts:1)Citrate modified gold nanoparticles(average particle size is about 13 nm)were prepared.The modified metal halide ions on the surface of gold nanoparticles were modified by ligand exchange.The optimal concentration of metal halide ions on the surface of gold nanoparticles was determined by uv-vis spectrophotometer as follows: chloride ion 5 mM,bromine ion 5 mM and iodine ion 1 mM.It was confirmed by transmission electron microscopy that gold nanoparticles still had good dispersion after modification by halogen ions.Raman spectra further confirmed that the halogen ions on the surface of gold nanoparticles were adsorbed on the surface of gold nanoparticles by chemical bonds.2)Choline phosphate liposomes(PC)were prepared by thin film hydration.The liposome leakage and differential scanning calorimetry experiments showed that the interaction between the iodide ion-modified gold nanoparticles and the phosphatidylcholine liposomes was weaker than that of the bromine and chloride-coated gold nanoparticles.Therefore,the halide can regulate the interaction between gold nanoparticles and choline phosphate liposomes on a very small scale.At the same time,we further studied the effects of different sizes of gold nanoparticles on the leakage of liposome contents.We used calcitrochlorin as a drug model to study the effects of different sizes of gold nanoparticles with the same surface modification on the release behavior of calcitrochlorin in liposomes.We found that at the same molar concentration,large size of gold nanoparticles led to more obvious leakage of calcitrochlorin in the liposomes,but the liposomes did not deposit on the surface of gold nanoparticles.3)Through the UV characterization,we found that liposomes can regulate the optical properties of gold nanoparticles.The nano-gold-lipid hybrid system has a certain absorption peak at 808 nm,so we further studied the photothermal properties of the nano-gold-lipid hybrid system.At the same time,because halogen ions can regulate the interaction between nanogold and liposome,resulting in varying degrees of leakage of liposome contents,we successfully prepared the liposome containing doxorubicin.The drug release experiment further confirmed the slow release effect of halogen ion on the drug in liposome induced by nano-gold.