Miniaturized Proteomic Sample Preparation

A method of forming a single-cell proteomic sample, said method comprising:

• a) dispensing n droplets of lysis buffer onto a substantially planar solid surface, wherein n≥2;
• b) dispensing a single cell into each of the n droplets of lysis buffer to produce n droplets, each comprising a lysed single cell;
• c) dispensing digestion buffer into each of the n droplets to digest proteins from each lysed single cell to produce n droplets comprising peptides;
• d) dispensing a chemical tag into each of the n droplets comprising the peptides to produce labeled peptides, wherein at least one droplet of the n droplets receives a different chemical tag from at least one other droplet of the n droplets, thereby enabling the labeled peptides in the at least one droplet to be distinguishable from the labeled peptides in the at least one other droplet;
• and
• e) applying a fluid to merge at least a subset of the n droplets into a combined droplet on the substantially planar surface, thereby combining the labeled peptides to form a single-cell proteomic sample.