The invention relates to the technical field of functionalized magnetic nano materials, and provides a composite magnetic nano material based on
DNA tetrahedrons, preparation and application. The preparation method comprises the following steps of synthesizing
DNA tetrahedrons through a self-
assembly reaction of
a DNA single chain, loading magnetic nano particles on the surface of
molybdenum disulfide particles, modifying gold nanoparticles on exposed active
sulfur atoms of
molybdenum disulfide particles, modifying the
DNA tetrahedrons on the gold nanoparticles, and incubating and connecting
protein antibodies on the DNA tetrahedrons. The material prepared by adopting the preparation method is used for enriching and detecting the low-abundance
protein in the serum, the specific low-abundance
protein in the serum can be efficiently and highly selectively enriched through a specific reaction between an
antigen and an
antibody, and the material takes a magnetic nano material as a matrix, so that the material has the advantages of simplicity, convenience and rapidness in use, the
treatment time of the serum
complex matrix is greatly shortened, and high-efficiency and high-selectivity enrichment of low-abundance proteins in the
complex matrix can be realized.