Universal pretreatment development for low-input proteomics using Lauryl Maltose Neopentyl Glycol

In recent years, the demand for low-input proteomics, most notably single-cell proteomics (SCP), has increased. In this study, we developed a Lauryl Maltose Neopentyl Glycol (LMNG)-assisted sample preparation (LASP) method that suppresses the loss of proteins and peptides in samples by adding LMNG, a surfactant, to the digested solution and removing the LMNG simply via reversed phase solid-phase extraction. The advantage of removing LMNG during sample preparation for general proteomic analysis is that it prevents mass spectrometry (MS) contamination. When the LASP method was applied to the low-input SP3 method and on-bead digestion in immunoprecipitation-MS, the recovery of the digested peptides was greatly improved. Furthermore, we established a simple and operationally easy sample preparation method for SCP based on the LASP method (scpLASP) and identified a median of 1,175 proteins from a single HEK239F cell using liquid chromatography (LC)-MS/MS with a throughput of 80 samples per day.