Phenylboronic　acid-functionalized　nanometer-sized　CaCO3　particles　(PBA-CaCO3)　were　designed　to　determine　the　carcinoembryonic　antigen　(CEA)　glycoprotein　with　a　portable　Ca2+　ion-selective　electrode　(Ca-ISE)　through　a　typical　boronate　ester　bond.　CaCO3　nanospheres　were　conjugated　to　3-aminophenylboronic　acid　by　amine-epoxy　reaction,　whereas　target　CEA　was　captured　into　the　aptasensing　interface　by　the　immobilized　thiolated　aptamer　on　gold　substrate.　Upon　PBA-CaCO3　introduction,　3-aminophenylboronic　acid　labeled　to　CaCO3　microsphere　specifically　recognized　with　CEA　glycoprotein　based　on　sugar-boronic　acid　interaction　to　form　a　sandwiched　complex.　The　carried　CaCO3　was　dissolved　under　acidic　conditions　to　release　Ca2+　ion　with　a　portable　Ca-ISE　readout.　Thanks　to　the　specific　boronate　ester　bond　between　PBA　and　1,2-diols,　the　synthesized　PBA-CaCO3　exhibited　good　conjugation　properties　for　CEA　glycoprotein.　Under　optimum　conditions,　Ca-ISE-based　aptasensing　platform　exhibited　good　electrode　potential　response　for　evaluation　of　target　CEA,　and　allowed　detection　of　CEA　at　a　concentration　as　low　as　7.3　pg　mL−1.　Importantly,　Ca-ISE-based　aptasensing　system　is　readily　extended　to　detect　other　disease-related　glycoproteins　by　controlling　the　corresponding　aptamer.　©　2020,　Springer-Verlag　GmbH　Germany,　part　of　Springer　Nature.