Theranostic nanoprobes are provided for overcoming cancer multidrug resistance, and methods for treating biological tissue, including cancerous tissue. The theranostic nanoprobes may include gold nanoparticles functionalized with DNA-hairpin. The DNA-hairpin may be configured to hybridize to a complementary target, which may silence or lessen the multidrug resistance of cancer cells. The theranostic nanoprobes may be configured to release a chemotherapeutic agent upon hybridization of the DNA-hairpin to a target molecule.
