Nano-silver film preparation method for high-efficiency detecting biomacromolecule and microbe

The invention discloses a method which prepares a nano silver film that is used for detecting biological macromolecules and microorganisms in high efficiency, the method adds solid particles of silver nitrate (AgNo3) and solid particles of polyvinyl alcohol (PVA) into high-purity water with the electric conductance less than 0.2 microseconds per centimeter and heats the high-purity water until the solid particles are completely dissolved, a mixture solution with all dissolved solid particles is taken as an electrolyte, and one surface of a substance that has a negative charge and two even surfaces without slopes is fixed on a container wall and led to contact with the electrolyte. Two silver rods with the purity equal to or more than 99.5 percent are inserted into the electrolyte, direct current voltage of 25 to 50 V is applied, electricity is supplied for 1 to 3 hours, the electrolyte and a substrate are then positioned in a heliophobe place for 12 to 24 hours, and then the substrate is taken out and dried.