Protein Targeted Quantification

Protein Target Quantification aims to accurately measure the abundance of specific proteins in biological samples. It has the advantages of high throughput, accuracy, and reproducibility. Using early data from differential proteomics/transcriptomics/genomics analysis, this method has validated biomarkers in large biological sample sizes. Targeted quantification selectively collects and analyses quantitative mass spectrometry data of peptides of interest, achieving higher sensitivity and accuracy in hundreds or thousands of samples. By adding stable isotope standards to the sample, targeted quantification can perform absolute quantification of proteins of interest. It can be applied to signal pathway research, tumor biomarker research, post-translational modification analysis, and serve as an alternative to antibody-based protein quantification methods for targeted protein quantification.

 

What are the Targeted Protein Quantification Techniques?

Targeted quantification proteomics mainly includes MRM/SRM and PRM. MRM (Multiple Reaction Monitoring), also referred to as SRM (Selective Reaction Monitoring), is a classic targeted protein analysis method that relies on triple quadrupole mass spectrometry. On the other hand, the latest PRM (Parallel Reaction Monitoring) technology is based on the next-generation high-resolution Orbitrap mass spectrometry technique.

 

PRM relies on high-quality, accurate/high-resolution mass spectrometry instruments, producing targeted quantification results that are more selective, sensitive, and repeatable than SRM. In addition, PRM has enhanced anti-interference ability in complex backgrounds. From a practical implementation standpoint, PRM has the advantages of a simpler procedure and lower cost than SRM, specifically:

 

1. Pre-Designed Precursor/Fragment Ion Pairs for Target Proteins are Not Required, Saving Experimental Design and Operation Time

2. The Inclusion of Synthetic Standard Peptides is Flexibly Selectable, Potentially Saving Significant Cost

 

In terms of applications, PRM can replace traditional Western blot technology. On one hand, it liberates protein validation from commercial antibodies and can be applied to various non-model organisms. On the other hand, it allows for high-throughput protein validation on large-scale biological samples, thereby improving experimental efficiency.