The　localization　and　distribution　of　cell　membrane　proteins　play　an　important　role　in　the　occurrence　and　development　of　diseases,　and　in-situ　characterization　of　nanoscale　membrane　proteins　requires　single　molecule　level　technology.　To　achieve　high-resolution　imaging　of　biological　samples　in　the　liquid　environment,　a　single　molecule　imaging　technology　based　on　scanning　electron　microscopy　(SEM)　was　developed.　A　combination　of　scanning　transmission　imaging　device　and　a　commercial　liquid　chip　device　were　used　to　observe　the　distribution　and　polymerization　state　of　membrane　protein　EGFR　in　triple　negative　breast　cancer　(TNBC)　cells.　Results　show　that　the　images　resolution　reaches　about　2　-　3　nm.　The　experimental　conditions　of　the　ESEM　included　an　accelerating　voltage　of　30　kV,　a　beam　current　of　10-　10　A　in　a　high　vacuum　environment.　Because　ZnS@　CdSe　quantum　dots　and　gold　particles　have　higher　atomic　number　than　liquids　and　organisms,　better　contrast　and　signal-to-noise　ratio　in　imaging　were　obtained.　This　technology　provides　an　advanced　in-situ　method　and　observation　platform　for　high-resolution　imaging　in　the　cell　biology　field.　©　2024　Beijing　University　of　Technology.　All　rights　reserved.