In　this　work,　a　split-type　dual-mode　(colorimetric/photothermal)　immunoassay　method　was　designed　for　point-of-care　testing　(POCT)　detection　of　mycotoxins　(aflatoxin　B1,　AFB1　as　the　model　analyte)　in　foodstuffs　based　on　Pt　supported　on　nitrogen-doped　carbon　amorphous　(Pt-CN).　The　as-synthesized　Pt-CN　exhibits　excellent　peroxidase-mimicking　activity,　which　can　catalyze　the　oxidization　of　3,3′,5,5′-tetramethylbenzidine　(TMB)　into　TMBox　with　sensitive　colorimetric　readout　in　the　presence　of　hydrogen　peroxide　(H2O2).　Moreover,　the　TMBox　also　serves　as　a　near-infrared　(NIR)　photothermal　agent　to　convert　the　colorimetric　readout　into　heat　under　the　irradiation　of　an　808　nm　laser.　A　competitive-type　immunoreaction　is　carried　out　between　AFB1　and　glucose　oxidase　(GOx)-labeled　AFB1-bovine　serum　albumin　(AFB1-BSA-GOx)　conjugates.　With　the　formation　of　immune　complexes,　the　entrained　GOx　catalyzes　the　hydrolysis　of　glucose　to　generate　H2O2,　which　further　involves　the　Pt-CN　catalyzed　production　of　TMBox　to　increase　colorimetric/photothermal　readouts.　Depending　on　the　degree　of　TMB　oxidation,　the　dual-mode　immunoassay　provides　a　linear　range　of　1.0　pg/mL　to　10　ng/mL,　with　a　limit　of　detection　(LOD)　of　0.22　pg/mL　for　the　colorimetric　assay　and　0.76　pg/mL　for　the　photothermal　assay.　Moreover,　the　developed　method　is　successfully　used　to　detect　AFB1　in　peanuts　with　acceptable　accuracy　compared　with　commercially　enzyme-linked　immunosorbent　assay　(ELISA)　kits.　Significantly,　the　photothermal　readout　in　this　method　is　recorded　on　a　mobile　phone　device　without　any　expensive　instruments,　providing　an　affordable　and　convenient　tool　for　food　safety　testing.　©　2022　Elsevier　B.V.