Preparation And Biological Application Of Silver Selenide Quantum Dots

Near-infrared quantum dots have the characteristics of small background interference and large penetration depth.The main reason is that the near-infrared band is seen as the"second biological window"?700-900 nm?.It has become a recognized ideal fluorescent probe because it could make up for the interference of the traditional visible light region quantum dots with the fluorescence of the biological tissue itself and the insufficiency of the traditional organic fluorescent dyes.This makes the near-infrared quantum dots have advantages in biological imaging applications because it can overcome the drawbacks of deep-tissue imaging in the visible light region quantum dots.The focus of this paper is to find silver selenide quantum dots with excellent optical properties by changing the ratio of Ag and Se in the quantum dots.And then,use the distearoyl phosphatidylethanolamine-polyethylene glycol?DSPE-PEG?to modify its surface from the oil phase to the aqueous phase to achieve its fluorescence probe as a fluorescence marker for biological cells.The specific research contents are as follows:This article briefly introduces the properties and applications of silver-containing quantum dots,and summarizes the optical properties,physical effects of quantum dots,and their applications in biology.Silver selenide?Ag2Se?QDs with different ratios were obtained by changing the ratio of Ag and Se,and the UV-Vis-NIR spectrophotometer was used to determine the absorption spectra of the materials and to test their optical stability.The experimental results show that the quantum dots have good optical stability when the ratio of Ag to Se is 1:1,so the Ag-Se is used as the 1:1 disulfide silver?Ag₂Se?quantum dots for distearoyl phosphatidylethanolamine-The modified polyethylene glycol?DSPE-PEG?was used to physically characterize the silver selenide QDs before and after modification.Subsequently,the silver selenide QDs were tested using cytotoxicity tests,colloidal stability tests,and cell fluorescence imaging tests to prove that the toxicity of the modified silver selenide QDs was kept at about 25%to prove its low toxicity.The experimental results showed that The good optical stability of silver QDs can be widely applied in the fields of cell biomarkers,bioimaging,targeted localization,and targeted therapeutics,laying the foundation for the biological applications of quantum dots silver selenide.