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Hi y'all come swing by my twitter poster for #RSCPoster #RSCAnalytical #RSCChemBio !!! Just kidding, you're already here! I'll be loitering around it trying to look inconspicuous all day! 
It's about an age-old technique rigorously validated for an ultra-modern application...
So let me walk you through it ;)
We are very, very interested in doing single cell proteomics--but losses (to surfaces) when lysing and digesting a single cell are a challenge!!
We wanted a lysis and digestion technique that was super easy, high-throughput, and could be directly analyzed by mass spectrometry (MS) without cleanup-- removing certain chemicals incompatible with MS almost certainly means losses! Pie in the sky, eh...
Enter mPOP -- after trying many types of lysis (lyses?) we found a simple freeze-heat cycle extracts proteins!
To prove it rigorously across the whole proteome, we directly compared it to a urea lysis using SILAC quantitation!
Lysing the exact same number of cells, we looked at the distribution of protein quantitation for the two conditions: mPOP is in the numerator, Urea in the denominator --- Voila! The distribution of ratios is centered above 1 (0 on Log2 scale)
Confident mPOP can extract proteins well, let's do single cell proteomics! First we made a standard and diluted it to single-cell levels so we could optimize our instrument!
We were able, with the standard, to use the quantitative information from hundreds of measured proteins to separate the single cells based on cell type!
FInally, we moved into high-throughput mode!
And, from real single cells, were able to measure hundreds of proteins, which in turn allowed us to separate the single cells by cell type!
Phew!! think I doubled my number of overall tweets with this thread!
Standard made using the SCoPE-MS experimental design, more about that here: doi.org/10.1186/s13059…
