The invention discloses an SERS sensor for integrated detection of tumor
protein and
nucleic acid markers and a preparation method thereof. The SERS sensor comprises a silver
nanorod array substrate and an SERS probe, wherein the surface of the silver
nanorod array substrate is modified with a tetrahedral
DNA structure; the tetrahedral
DNA structure is formed by self-assembling six
DNA single chains, and three DNA single chains are arranged on three edges of the tetrahedral DNA structure, are respectively connected with three capture chains and are used for respectively and specifically binding
nucleic acid and a
protein marker. The detection limits of the SERS sensor for detecting
nucleic acid and
protein respectively reach the Amol / L magnitude and the fg / mL magnitude; the integrated detection of various nucleic acid and
protein biomarkers in complex environments such as serum can be realized. The sensor disclosed by the invention is simple to prepare, high in detection sensitivity and good in reliability, can realize high-sensitivity detection of biomarkers with extremely low abundance in the early stage of
lung cancer, and has good universality for various
tumor biomarkers.