Biocatalytic Properties Of Liposome@Noble Metal Nanomaterials And NIR Light-controlled Drug Release Traced By SERS

Noble metal nanomaterials have many excellent optical properties due to their unique plasma resonance properties.In addition,their biocatalytic properties have attracted much attention.Compared with natural enzymes,noble metal nanomaterials are not easily denatured and inactivated as nano-biomimetic enzymes,and have high stability and catalytic activity.They have broad application prospects in biosensing,molecular detection and other fields.Among them,gold and silver nanomaterials are popular research directions in recent years due to their excellent tunable optical properties,stability and biocatalytic properties.In this paper,a multi-functional bio-application platform with biocatalysis,photothermal effect and Raman enhancement effect is designed.The main research contents are as follows:(1)Preparation of liposome @Au core-shell nanocomposites and liposome @Ag/Au nanocomposites by chemical reduction method.The composition ratio of the components was changed to perform plasmon resonance optical control,the relationship between photothermal and corresponding optical absorption was studied.The influence factors of photothermal effect are explored and the photothermal conversion efficiency is calculated.The prepared nanomaterials were used as SERS substrates to investigate their SERS properties.(2)Liposome @Ag/Au nanocomposites have biocatalytic properties,can catalyze the decomposition of hydrogen peroxide,and add 3,3 ',5,5'-tetramethylbenzidine(TMB)as a coloring solution,colorless TMB is oxidized to blue oxidized TMB(oxTMB).The characteristic absorption intensity of oxTMB at 652 nm has a corresponding relationship with the hydrogen peroxide concentration,Thus,hydrogen peroxide can be detected.(3)The liposome @Ag/Au nanocomposite is loaded with the drug doxorubicin hydrochloride,which can be used for photothermal therapy and drug synergistic treatment.In addition,it can be co-cultured with cells to distinguish cancer cells from normal cells by Raman spectroscopy.Liposome @Ag/Au nanocomposites can be used as SERS probes and loaded with probe molecules to monitor the endocytosis process.This indicates that liposome@Ag/Au nanocomposites can be used as a multi-functional platform for photothermal therapy,drug delivery and bioassay.