4D-DIA Quantitative Proteomics

The greatest challenge in traditional DIA without ion mobility separation lies in the difficulty of reliably analyzing mixed spectra. During quantification, matching is mainly based on chromatographic elution time (retention time). However, due to co-elution, the retention time alone is not enough, and many other interfering signals will affect the detection accuracy.

4D technology provides ion-mobility separation and adds an extra dimension for calibration. It can accurately discriminate the specific peptide signals from the mixed spectra of DIA, effectively reducing spectra complexity and improving the detection accuracy and reliability of DIA.

In the 4D-diaPASEF scanning mode, the ion-mobility-related CCS value correlates well with m/z. This feature allows the Quadrupole to scan gradually to collect nearly 100% of the ion signals, greatly enhancing the sensitivity and depth of detection.

In comparison, in the traditional LC-MS/MS-based proteomics without ion mobility separation, only limited signals can be collected.

4D-DIA identifies and quantifies low-abundant proteins more accurately than traditional methods, thereby increasing the depth of proteomics detection.

4D-DIA technology can further push the limits of sensitivity with advanced instrument performance and upgraded acquisition methods. Even at this trace level, 4D-DIA showed 85% data integrity for protein quantification.