Bimetallic ZrHf-based metal-organic framework embedded with carbon dots: Ultra-sensitive platform for early diagnosis of HER2 and HER2-overexpressed living cancer cells

Biosens Bioelectron. 2019 Jun 1:134:8-15. doi: 10.1016/j.bios.2019.03.043. Epub 2019 Mar 22.


We report here a new bimetallic ZrHf metal-organic framework (ZrHf-MOF) embedded with abundant carbon dots (CDs) (denoted as CDs@ZrHf-MOF), which exhibits strong fluorescence and rich-amino-functionalization. The CDs@ZrHf-MOF can be applied as the scaffold for anchoring aptamer strands to determine human epidermal growth factor receptor-2 (HER2) and living HER2-overexpressed MCF-7 cells. The basic characterizations reveal that the CDs are embedded within the interior cavities of ZrHf-MOF without varying the nanostructure, leading to good biocompatibility, strong fluorescence, and high electrochemical activity of CDs@ZrHf-MOF. As compared with the pristine ZrHf-MOF, the CDs@ZrHf-MOF-based electrochemical aptasensor displays better sensing performances toward both HER-2 and MCF-7 cells, giving an extremely low detection limit of 19 fg mL-1 (HER2 concentration range: 0.001-10 ng mL-1) and 23 cell mL-1 (cell concentration range: 1 × 102~1 × 105 cell mL-1), with good selectivity, stability, reproducibility, and acceptable applicability. The proposed strategy for developing CDs@ZrHf-MOF-based aptasensor is promising for the early and sensitive detection of cancer markers and living cancer cells.

Keywords: Detection of MCF-7 cells; Early diagnosis of HER2; Electrochemical aptasensor; ZrHf-based metal–organic framework.

Publication types

  • Evaluation Study

MeSH terms

  • Aptamers, Nucleotide / chemistry*
  • Biosensing Techniques / methods*
  • Breast Neoplasms / diagnosis*
  • Carbon / chemistry
  • Early Detection of Cancer
  • Female
  • Hafnium / chemistry*
  • Humans
  • Limit of Detection
  • MCF-7 Cells
  • Metal-Organic Frameworks / chemistry*
  • Nanostructures / chemistry
  • Receptor, ErbB-2 / analysis*
  • Reproducibility of Results
  • Zirconium / chemistry*


  • Aptamers, Nucleotide
  • Metal-Organic Frameworks
  • Carbon
  • Zirconium
  • ERBB2 protein, human
  • Receptor, ErbB-2
  • Hafnium