Chromatogram Display Retention Index Cross-Detector Comparison

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Comparing measurement results from different detectors in a chromatograph is challenging due to varying retention times, which are influenced by differences in column length and measurement conditions, making it difficult and time-consuming to identify identical target components across multiple detectors.

Innovation Solution

A method that involves determining standard and calibration retention times for each detector, computing a retention index, and displaying chromatograms within a defined time range based on this index, allowing for easy comparison of measurement results across detectors without the need for measuring a standard sample with each detector.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple detectors are used to measure the same target component, then the reliability of identification is improved, but the difficulty of comparing measurement results increases due to retention time variations

Engineering Contradiction:

Improveidentification reliabilityVSAvoidcomparison difficulty

Core Design Contradiction:

ReliabilityVSDifficulty of detecting and measuring

Solution Approach 1:

The patent transforms the time domain parameter (retention time) into a dimensionless retention index by establishing a mathematical relationship with calibration components. This parameter transformation eliminates the direct dependence on absolute retention time values, allowing consistent identification across different detectors despite retention time variations.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces calibration components as an intermediary reference system. By measuring both target components and calibration components with each detector and establishing retention index relationships, the calibration components serve as a mediator that enables comparison across different detectors without requiring direct measurement of target components with all detectors.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If standard retention time is determined by measuring standard samples with each detector, then the accuracy of target component identification is improved, but the time required for comparison increases

Engineering Contradiction:

Improveidentification accuracyVSAvoidcomparison time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent performs preliminary measurement and calibration by measuring both target components and calibration components with the first detector to establish retention index relationships before using the second detector. This preliminary action creates a reference framework that eliminates the need to measure standard samples with every detector, significantly reducing the time required for subsequent comparisons.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent creates a virtual standard retention time for the second detector by copying and transforming the retention index relationship established from the first detector's measurements. Instead of physically measuring standard samples with the second detector, the system computes equivalent retention times based on the retention index, which is insensitive to detector-specific variations.

Inventive Principle:

Principle #26Copying

3Ease of manufacture

If retention time is used directly for component identification, then the simplicity of the method is maintained, but the adaptability to different detectors decreases

Engineering Contradiction:

Improvemethod simplicityVSAvoiddetector adaptability

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent creates a universal retention index system that functions across multiple different detectors. By establishing retention index relationships based on calibration components measured with each detector, the system achieves detector-agnostic identification capability while maintaining operational simplicity through automated computation and display of chromatograms in the retention index domain.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS10203309B2Chromatogram display method, chromatogram display device, and chromatograph comprising said device

Publication Date: 2019.02.12 SHIMADZU CORP

AI summary

Chromatographs of a measurement target sample measured in FID and MS are displayed on display unit in a time range defined with reference to the retention index of the target component computed based on the standard retention time and calibration retention time for the target component in FID. The retention index is not readily influenced by difference in column length, thus making it possible to display the peaks of the target component measured with FID and MS in a corresponding time range by displaying the chromatograms on display unit in a time range defined with reference that retention index. Therefore, even in cases where the retention times of the target component in FID and MS are different, measurement results for an identical target component from FID and MS can be easily compared.