Is DDA Considered as Untargeted Quantitative Proteomics?

DDA (Data-Dependent Acquisition) is one of the methods of non-labeled quantitative proteomics. In proteomic research, quantitative methods are roughly divided into two categories: labeled quantification and non-labeled quantification. DDA is a commonly used non-labeled quantitative method that relies on the data-dependent mode of the mass spectrometer to select specific precursor ions for further fragment analysis. This method does not require pre-chemical labeling of proteins or peptides, thus simplifying the sample processing process. DDA is widely used in proteomics, especially in the identification and quantitative analysis of proteins in complex samples.

 

The key points of DDA (Data-Dependent Acquisition) technology are as follows:

 

1. Fundamentals of Mass Spectrometry Analysis

DDA is a non-labeled quantitative proteomics method based on mass spectrometry technology. It identifies proteins by analyzing the mass and fragment spectra of peptides or proteins.

 

2. Automatic Selection of Precursor Ions

During the MS (Mass Spectrometry) scan, DDA automatically selects a certain number of the strongest signal peptide ions (precursor ions) for MS/MS (Tandem Mass Spectrometry) scan.

 

3. Fragmentation Analysis

The selected peptide ions are fragmented in the MS/MS scan to produce specific fragment spectra. These spectra are crucial for identifying specific protein sequences.

 

4. Application Range

DDA is suitable for the identification and quantitative analysis of proteins in complex samples, and is widely used in proteomic research.

 

5. Advantages

Easy to operate, suitable for a wide range of sample types, and can effectively identify and quantify various proteins.

 

6. Limitations

The detection sensitivity for low abundance proteins is relatively low, and the reproducibility of the results is affected by the complexity of the sample and the performance of the mass spectrometer.