Lanthanide Nanoprobes for the Multiplex Evaluation of Breast Cancer Biomarkers

Metal stable isotope tagging has demonstrated great and unique success in the multiplex and ratiometry-based accurate detection of biomolecules and single cells, while its sensitivity is regarded as an Achilles' heel. Although lanthanide nanoparticles remain the most promising tags for elemental mass spectrometry, there is no report on the lanthanide nanoparticle-based multiplex immunoassay of disease markers in clinical serum samples because of their tough synthesis and bioconjugation and a complex physiological sample matrix. Herein, to fill this gap, multiple lanthanide nanoparticle tags (NaEuF₄, NaTbF₄, and NaHoF₄) were delicately designed and facilely synthesized with a one-pot solvothermal method for the multiplex evaluation of breast cancer biomarkers carcinoembryonic antigen (CEA), CA153, and CA125 in human serum samples. The proposed method exhibited wide linear ranges and low levels of the detection limit for all biomarkers. The test results were consistent with the routine electrochemiluminescence results in clinical serum samples, which proved the possibility of the early prognosis of breast cancer as well as improving the surgical outcome prediction.