Tracer particle and application method and preparation method thereof

The invention provides a tracer particle, and an application method and a preparation method thereof. The tracer particle comprises: a core structure; a nucleic acid molecule which is fixed on the core structure; and a shell layer covering the core structure and the nucleic acid molecule, wherein the core structure has a first porosity, the shell layer has a second porosity, and the first porosity is greater than the second porosity. The tracer particle disclosed by the invention has a core structure with moderate porosity, so that the fixed quantity of nucleic acid molecules is increased, the thermal conductivity of the particle is reduced (thermal resistance is reduced), and the temperature tolerance of the tracer particle is further improved. In addition, the tracer particle also has the properties of acid resistance, alkali resistance and the like, and the tolerance and the recovery rate of the tracer particle in an extreme environment can be further improved. 本发明提供一种示踪粒子及其应用方法与制备方法，该示踪粒子包括：一核心结构；一核酸分子，固定