Antibody-small molecule drug conjugate capable of inhibiting tumor growth, and preparation method and application thereof

The invention relates to an antibody-small molecule drug conjugate capable of inhibiting tumor growth, and a preparation method and application thereof. The invention provides an anti-Her2 antibody-small molecule drug conjugate (antibody-drug conjugate or ADC). The traditional monoclonal antibody is subjected to conjugate modification, and an unresectable chemical linker with higher stability than the traditional chemical linker is selected before systemic circulation. The conjugate has higher targeting property than the traditional chemotherapy and radioactive therapy. Compared with the traditional anti-Her2 monoclonal antibody, the conjugate has better drug effect healing windows. The conjugate has higher stability in systemic circulation, and lowers the toxicity of the drug before entering the tumor cells. The invention provides a preparation method and application of the antibody-small molecule drug conjugate.