Vascular　endothelial　growth　factor　(VEGF)　is　a　crucial　signaling　protein　for　the　tumor　growth　and　metastasis,　which　is　also　acted　as　the　biomarkers　for　various　diseases.　In　this　research,　we　fabricate　an　aptamer-antibody　sensor　for　point-of-care　test　of　VEGF.　Firstly,　target　VEGF　is　captured　by　antibody　immobilized　on　the　microplate,　and　then　binds　with　aptamer　to　form　the　sandwich　structure.　Next,　with　the　assist　of　glucose　oxidase　(GOx)-functionalized　ssDNAs,　hybridization　chain　reaction　occurs　using　the　aptamer　as　the　primer.　Thus,　GOx　are　greatly　gathered　on　the　microplate,　which　catalyzes　the　oxidization　of　glucose,　leading　to　the　pH　change.　As　a　result,　the　detect　limit　at　a　signal-to-noise　was　estimated　to　be　0.5 pg/mL　of　target　by　pH　meter,　and　1.6 pg/mL　of　VEGF　was　able　to　be　distinguished　by　naked　eyes.　Meanwhile,　this　method　has　been　used　assay　VEGF　in　the　serum　with　the　satisfactory　results.　©　2017