SERS Study Of RC Plasma Based On Ag-NPs-TCA Membrane Composite Substrate

Cancer,also known as malignancy,is a pathological process that poses a serious threat to human health and is characterized by uncontrolled cell replication,often accompanied by reduced differentiation.Surface Enhanced Raman Scattering(SERS)detection technology can overcome the limitation of weak signal of traditional Raman spectrum,and has the advantages of high sensitivity and fast detection,which has been widely used in cancer diagnosis research as an efficient detection tool.In order to better apply surface-enhanced Raman spectroscopy to qualitative and quantitative analysis of biochemical molecules in cancerous bodies,the prepared substrate should have the characteristics of good uniformity and high sensitivity.As for the application of surface-enhanced Raman spectroscopy in cancer detection,researchers have conducted a lot of studies and made preliminary progress,but there is still a lack of substrates with a large number of controllable "hot spots",good uniformity,reliable performance and easy preparation.To solve this problem,in this paper,three-dimensional Ag NPs composite substrate was prepared using the porous membrane of Tri-cellulose Acetate(TCA)as template,and its SERS performance was studied and analyzed.This composite substrate TCA porous membrane structure had strong adsorption capacity for probe molecules,and the charge transfer process in the composite structure also made a certain contribution to SERS enhancement.Therefore,the substrate has the advantages of good uniformity and high sensitivity.In addition,the substrate preparation operation is simple,low cost,can be large-scale production and use.This study is expected to provide a new method for early cancer screening using SERS.The main research of this paper are as follows:1.Preparation of TCA porous structure film.The effect of cellulose triacetate polymer concentration and dichloromethane solvent concentration on porous membrane was studied.It can be seen from the results that the TCA porous membrane formed when the concentration of polymer solution is 1.2% has a relatively regular structure,while the TCA porous membrane formed when the concentration is higher than 1.2% or lower than 1.2% cannot form a relatively regular structure.2.Rhodamine 6G molecule was used as the probe to study the SERS performance of the composite substrate based on Ag NPs-TCA porous membrane.The minimum detection concentration of probe molecule R6 G could reach 10-9 M by SERS detection based on the Ag NPs-TCA porous membrane composite substrate.3.The above prepared composite substrate based on Ag NPs-TCA porous membrane was beneficial to improve the sensitivity and specificity of SERS detection in plasma.The base was used for the detection of renal cancer and plasma samples from healthy volunteers.The sensitivity and specificity of PCA and LDA were 100% and 100%,respectively.4.The above prepared Ag NPs-TCA porous membrane composite substrate was used for the detection of kidney cancer and bladder cancer plasma samples.Through PCA-LDA analysis,the diagnostic sensitivity and specificity of renal cancer and bladder cancer were 96.7% and 90%,respectively.