Figure 1.

Schematic overview of time-of-flight MC for simultaneous analysis of multiple platelet surface markers. (A) A platelet-specific panel of metal-tagged antibodies targeting surface antigens of interest was constructed. Each antibody is bound to 2–4 chelating polymers that are attached to stable lanthanide metal isotopes. Each polymer contains approximately 25–30 lanthanide ions of the same mass. (B) Platelets from a patient blood sample were incubated with the platelet-specific metal-tagged antibody cocktail under stimulating or non-stimulating conditions. Samples were fixed with 1% formaldehyde, washed with ddH₂0 to remove salts and filtered through a 35 µm cell strainer. (C) Samples were then analyzed using time-of-flight inductively coupled plasma MC. Samples were nebulized into single-cell droplets and passed through a 7500 K argon plasma where they were vaporized, atomized and ionized to form clouds of ions that correspond to individual cells. Each ion within the cloud was detected and separated according to mass and correlated with a specific metal-tagged probe present in the antibody cocktail. Abbreviations: Ab, antibody; ADP, adenosine diphosphate; CD, cluster of differentiation; GP, glycoprotein; La, Lanthanide; TRAP, thrombin receptor activating peptide.