This study aimed to generate a novel photoimmunoconjugate to specifically destroy MTf-positive melanoma and TNBC cells in vitro following NIR light irradiation.<h4>Methods</h4>A single-chain variable fragment (scFv) assembled from anti-MTf antibody L49 was recombinantly fused with the SNAP-tag protein (L49(scFv)-SNAP), capable of irreversible and autocatalytic conjugation to any O(6)-benzylguanine (BG) substrate in a 1:1 stoichiometry. The gene discussed is MELTF; the disease is melanoma.