APTBIO provides label-free methods for relative quantification, which a rapid and low-cost alternative to other quantitative proteomic approaches.
Label-free quantification is a method in mass spectrometry that aims to determine the relative amount of proteins in two or more biological samples. Unlike other methods for protein quantification, label-free quantification does not use a stable isotope containing compound to chemically bind to and thus label the protein.
Label-free quantification may be based on precursor signal intensity or on spectral counting. The first method is useful when applied to high precision mass spectra. The high-resolution power facilitates the extraction of peptide signals on the MS1 level and thus uncouples the quantification from the identification process. In contrast, spectral counting simply counts the number of spectra identified for a given peptide in different biological samples and then integrates the results for all measured peptides of the protein(s) that are quantified.
1) Protein GO analysis
2) Protein KEGG analysis
3) Differentially expressed proteins GO enrichment analysis
4) Differentially expressed proteins KEGG enrichment analysis
5) Differentially expressed proteins cluster analysis
6) Differentially expressed proteins PPI analysis