Kinetics of Protein Precipitation: optimizing recovery, purity, and throughput using the ProTrap XG

Jessica L. Nickerson1 , Alan A. Doucette 1

  1. Dalhousie University, Halifax, NS, Canada

Introduction

Efficient sample preparation is key to any proteomics workflow, with three priorities at the forefront: protein recovery, purity, and sample throughput. Acetone precipitation is a common method of purifying proteins from a complex sample prior to LC-MS/MS analysis, but is sometimes set aside due to seemingly variable yields.1 Our group previously established that the addition of 1-30 mM salt with 80% v/v acetone facilitates recoveries >95%.2 We later developed a filtration cartridge (ProTrap XG) which automates precipitation and SDS depletion.3 In order to maximize recovery, purity and sample throughput, we investigated the kinetics of protein precipitation with respect to structural properties of proteins, including molecular weight, hydrophobicity, and charge.