Hyaluronic acid-imitated polyamino acid derivative as well as preparation method and application thereof

The invention discloses a hyaluronic acid-imitated polyamino acid derivative, and belongs to the technical field of biological medicines. The derivative is PAsp[DET-DBCO(-ss-siRNA)&CDM]. The invention also discloses a preparation method of the derivative, which comprises the following steps: carrying out ring opening polymerization on a BLA-NCA monomer, synthesizing PBLA, reacting DET with PBLA to obtain PAsp(DET), further modifying the PAsp(DET), sequentially introducing sulfanilamide-DBCO-NHS and carboxydimethyl maleic anhydride on a side chain of the PAsp(DET) to obtain PAsp[DET-DBCO&CDM], carrying out a reaction on the PAsp[DET-DBCO&CDM] and a conjugate of 5'-amino siRNA and N3-PEG3-NHS to obtain a target macromolecule PAsp[DET-DBCO(-ss-siRNA)&cDM]. The invention provides a new approach for reducing parathyroid hormone, the gene expression for synthesizing parathyroid hormone is blocked from the source, and the parathyroid hormone reducing effect is good; and besides, the derivative synthesized by the inv