Droplet based low input proteomic platform for rare cell populations

Deep proteomic profiling of rare cell populations has been constrained by sample input requirements. Here, we present DROPPS, an accessible low-input platform that generates high-fidelity proteomic profiles of 100 - 2,500 cells. By applying DROPPS within the mammary epithelium, we elucidated the connection between mitochondrial activity and clonogenicity, discovering and validating CD36 as a marker of progenitor capacity in the basal cell compartment. We anticipate DROPPS will accelerate biology-driven proteomic research for a multitude of rare cell populations. ### Competing Interest Statement The authors have declared no competing interest.