Method for preparing nano silver film with enhanced Raman scattering substrate based on microwave technique

Abstract

The invention relates to a method for preparing a nano silver film with an enhanced Raman scattering substrate based on a microwave technique, which comprises the following steps: adding 50.0-90.0mg of silver nitrate, 100.0-140.0mg of polyvinyl alcohol and 10.0-30.0mg of sodium citrate to 200mL of ultrapure water to be dissolved and poured into a container; placing a glass slice which is cleaned by concentrated sulfuric acid into the 200mL of mixed liquid containing ammonia water and hydrogen peroxide to be soaked for 5-15 hours; cleaning the glass slice for 2-4 times respectively by tap water and the ultrapure water; tightly fixing the processed glass slice in the container and enabling one surface of the processed glass slice to be in contact with the mixed liquid containing the silver nitrate, the polyvinyl alcohol and the sodium citrate; placing the container which is filled with the glass slice and the mixed liquid into a microwave oven to be heated for 10-30 minutes; enabling the electropositive nano silver particles which are prepared by microwave heating to be absorbed on the glass slice, wherein the surface of the glass slice is electropositive; and taking out the glass slice out of the reaction solution to be dried, thereby obtaining the nano silver film with the infrared surface enhanced Raman scattering substrate. The method provided by the invention is simple and has the advantage of low cost, and the obtained nano silver film is stable and efficient and has the biological compatibility.

Description

technical field [0001] The invention belongs to the application of nanotechnology, and in particular relates to the technical field of a novel, high-efficiency, biocompatible NIR-SERS substrate nano-silver film preparation method. Background technique [0002] Surface-enhanced Raman scattering (SERS) spectroscopy has been widely used in physics, chemistry, biology and other aspects in recent years because it can detect single molecules. There are many preparation methods for the SERS substrate that must be used in this technology, mainly including chemical reduction method, electrolysis method, laser ablation method, vacuum evaporation method, magnetron sputtering and other methods. [0003] The SERS substrates prepared by different methods have their own advantages and disadvantages. For example, for the preparation of nano-silver sol, two methods, sodium borohydride reduction of silver nitrate and sodium citrate reduction of silver nitrate, are traditionally used, but it ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to overcome the problems of insufficient biocompatibility and versatility of most existing SERS substrates, and then provide a nano-silver thin film for efficiently detecting biological macromolecules as a NIR-SERS substrate. Electron nano-silver particles, so that the positively charged nano-silver particles are directly adsorbed in the colloid and precipitated on the surface of the negatively charged glass substrate