The invention relates to an in-situ magnetically-heated temperature-sensitive targeted nano
drug carrier for the reversal of multi-
drug resistance in tumors, which can implement in-situ heating in tumor areas and simultaneously control the release of drugs, so that
tumor cells having had
drug resistance can be sensitive to
chemotherapy drugs again under the double action of thermotherapy and
chemotherapy, thereby realizing the reversal of multi-
drug resistance of the
tumor cells. The nano carrier is in a core-shell structure prepared from amphipathic temperature-sensitive
copolymer, wherein the inner core layer is prepared from hydrophobic
polylactic acid segments; the outer shell layer is prepared from hydrophilic temperature-sensitive
polymer segments; and hydrophobic superparamagnetic nano particles and drugs are packed in the inner core layer. The nano
drug carrier disclosed by the invention overcomes the defect of low
chemotherapy drug distribution in tumor tissues in the existing process of thermotherapy-chemotherapy combined reversal of multi-
drug resistance in tumors, and simultaneously satisfies the following two
key factors for maximizing the thermotherapy and
chemotherapy effects: the synchronicity of chemotherapy and thermotherapy and the
controllability of the optimal temperature for chemotherapy and thermotherapy. The nano
drug carrier disclosed by the invention can be well used for primary and acquired multi-
drug resistance in tumors.