Isolation and detection of target cells in blood via immunomagnetic separation and atomic emission spectroscopy.

The identification and quantification of cells in blood can serve to inform disease diagnosis and prognosis for patients. However, sample complexity presents a challenge for achieving sensitive and specific detection methods. Furthermore, there is a need to alleviate current standard clinical protocols from operator burden, limit the required sample volumes, and to reduce analysis timescales, all while maintaining sensitivity. This study presents a novel atomic emission cytometry assay for the detection of cells in blood with high specificity and sensitivity (LOD = 84 cells per μL), requiring only 500 μL sample volume and 1 hour of combined processing and analysis time, exhibiting the potential for broad applications in disease diagnosis. Metal nanoparticles equipped with antibodies serve as a targeted cell labeling platform, as well as an integrated method for immunomagnetic separation and subsequent quantification via microwave plasma-atomic emission spectroscopy (MP-AES) analysis. This assay can also be modified to include multiple types of metal-based nanoparticles and/or target multiple cell surface markers for simultaneous detection of different cell populations within the same sample. The simplicity, specificity, and efficiency of this assay mark it as a viable integrated diagnostic platform for cellular-based disease diagnosis.