Retention Time Trajectory Matching for Peak Identification in Chromatographic Analysis

Area of Science:

• Analytical Chemistry
• Chromatography
• Chemometrics

Background:

• Retention time drift in chromatographic measurements, caused by variations in temperature ramping rate and carrier gas flow, complicates peak matching and identification.
• Accurate peak identification is crucial for subsequent data analysis but is often challenging without mass spectrometry.
• Existing peak alignment methods frequently involve complex mathematical warping or transformations.

Purpose of the Study:

• To describe and validate a novel peak matching and identification method, Retention Time Trajectory (RTT) matching, for targeted analyses.
• To enable mass spectrometry-free peak identification using only chromatographic retention times.
• To develop a method robust against significant retention time drifts.

Main Methods:

• Retention Time Trajectory (RTT) matching utilizes two-dimensional (2D) curves formed by chromatographic peak retention times.
• RTTs from sample chromatograms are matched and statistically compared against pre-installed library RTTs for identification.
• An RTT hybridization method was developed to expand the RTT library without new chromatographic measurements.

Main Results:

• The RTT matching method successfully identified peaks associated with target compounds using only retention time data.
• The RTT hybridization method enabled effective peak matching even with severe retention time drifts.
• Validation through 3.15 × 10^5 experimental gas chromatograms and 2 × 10^12 tests on fruit metabolomics datasets confirmed the method's efficacy.

Conclusions:

• RTT matching provides a robust and accurate mass spectrometry-free approach for peak identification in targeted chromatographic analyses.
• The method is highly effective in overcoming challenges posed by retention time drift.
• The developed RTT hybridization technique significantly enhances library generation efficiency.