Preparation method and application of micro-environment responsive nano-bio-conjugate drug delivery system

The invention discloses a preparation method and application of a micro-environment responsive nano biological conjugate drug delivery system. The preparation method comprises the following steps: preparing hydroxychloroquine-loaded retinol and maleimide group boric acid ester modified nanoparticles HNP-B, and then covalently binding maleimide groups on the surface of the HNP-B and sulfydryl on the surface of engineered extracellular vesicles aEV to obtain the nano bio-conjugate drug delivery system HNP-B-aEV. The HNP-B-aEV can responsively release target nanoparticles HNP modified by retinol and engineered extracellular vesicles aEV under the condition of high reactive oxygen species (ROS) in a hepatic fibrosis microenvironment, and consumes the ROS to improve the hepatic fibrosis pathological microenvironment at the same time. The released HNP can be specifically and accurately targeted to the activated hepatic stellate cells, so that the specific activation inhibition of the hydroxychloroquine on the hepat