An　innovative　signal-transduction　tag　with　glucose-doped　calcium　carbonate　nanospheres　was　utilized　as　the　label　of　a　secondary　antibody　to　design　a　nano-labelled　immunosorbent　assay　(NLISA)　of　a　carcinoembryonic　antigen.　The　signal　was　achieved　on　a　personal　glucometer　via　the　released　glucose　molecules　from　the　nanospheres　under　acidic　conditions　after　formation　of　the　sandwiched　immune　complexes.　The　enzyme　and　the　spectrometer　in　the　conventional　enzyme-linked　immunosorbent　assay　(ELISA)　were　replaced　by　a　glucose-doped　calcium　carbonate　nanosphere　and　a　glucometer.