Quantification of Proteins by Label-Free LC-MS/MS
Quantitative proteomic profiling is becoming a widely used approach in systems biology and biomarker discovery. There is a growing realization that quantitative studies require high numbers of non-pooled samples for increased statistical power. We present a descriptive protocol for label-free quantitation of proteins by LC-MS/MS that enables to obtain both quantitative and qualitative information in one study without the need to pool samples or label them.
Key wordsLabel free proteomics LC-MS, MSE time alignment nanoLC-MS/MS quantitation relative quantitation
The research was kindly supported by the Stanley Medical Research Institute (SMRI). We also thank Psynova Neurotech® for center support and for Ph.D. funding. The service team from Waters Corp. is acknowledged for its technical support and assistance.
We would also like to present our appreciation to Dr. Hassan Rahmoune and Mr. Emanuel Schwarz of the Cambridge Center for Neuropsychiatric Research for the helpful discussions and suggestions.
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