Flow Cytometer Cross-Standardization Using Fluorophore Bead Sets

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Standardization of flow cytometers, particularly spectral cytometers, is time-consuming and complex due to subtle differences in instrument hardware, making it difficult to calibrate using conventional methods with hard dye beads or fluorophores.

Innovation Solution

A method using a calibration set of bead populations with different fluorophores attached to their surfaces, measuring data signals across fluorescence channels, calculating a quantitative metric of fluorescence intensity, and adjusting channels to achieve standardized settings, applicable to spectral flow cytometers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional calibration methods using hard dye beads are used, then instrument standardization is achieved, but the process becomes time-consuming and complex due to subtle hardware differences

Engineering Contradiction:
Improvestandardization accuracyVSAvoidcalibration time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent changes the calibration parameter from using hard dye beads with broad spectrum emission to using fluorophores with specific excitation and emission wavelengths. This parameter change allows for more precise matching between calibration standards and instrument detectors, reducing the complexity of accounting for hardware variations while maintaining standardization accuracy.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The calibration process is segmented into specific wavelength channels corresponding to individual fluorophores rather than using a single broad-spectrum standard. This segmentation allows each detector channel to be calibrated independently with a fluorophore that matches its specific wavelength range, reducing the overall complexity and time required for standardization.

Inventive Principle:
Principle #1Segmentation

2Measurement precision

If spectral flow cytometers with large numbers of detectors are used, then comprehensive fluorescence spectrum quantification is achieved, but the standardization process becomes even more strenuous and complex

Engineering Contradiction:
Improvefluorescence spectrum quantificationVSAvoidstandardization complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent creates a universal calibration approach where a set of fluorophores with known spectral properties can be used across multiple detector channels. Each fluorophore serves multiple functions by contributing to the calibration of several adjacent wavelength channels, reducing the overall complexity of standardizing spectral flow cytometers with many detectors.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

Fluorophores are introduced as intermediary calibration standards that bridge the gap between the light source and the detectors. These fluorophores have well-characterized excitation and emission spectra that serve as reference points, simplifying the standardization process by providing intermediate reference measurements rather than directly calibrating each detector against primary standards.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Measurement precision

If fluorophores are used for calibration instead of hard dye beads, then subtle hardware differences are better accounted for, but the implementation becomes more challenging

Engineering Contradiction:
Improvehardware variation compensationVSAvoidcalibration implementation
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent applies preliminary action by pre-characterizing the excitation and emission spectra of the fluorophores used for calibration. This preliminary spectral characterization data is stored and used to automatically guide the calibration process, reducing the implementation challenge by providing advance reference information rather than requiring complex real-time adjustments.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The calibration process uses feedback from measured fluorescence signals to automatically adjust and optimize the calibration parameters. The system measures the actual fluorescence emission from known fluorophore concentrations and uses this feedback to refine the calibration curves, making the implementation more straightforward by allowing self-correction rather than requiring manual optimization.

Inventive Principle:
Principle #23Feedback

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach efficiently and accurately accounts for subtle differences in instrument hardware, enabling effective cross-standardization of flow cytometers, reducing calibration time and cost while maintaining consistent data comparison across instruments.

Implementation Method 1

each bead population of the calibration set includes a different fluorophore attached to a surface thereof

Methodology Applied
Scientific EffectFluorescence: Fluorescence

Data Source

PatentEP4703707A1Methods and compositions for flow cytometer calibration
Publication Date: 2026.03.04 BECTON DICKINSON & CO
  • EP4703707A1 patent drawingFigure 1A
  • EP4703707A1 patent drawingFigure 1B
  • EP4703707A1 patent drawingFigure 1C

AI summary

The present disclosure provides improved and useful techniques for cross-standardization of flow cytometry instruments and, particularly, spectral flow cytometry instruments. Aspects of the disclosure include methods of calibrating a flow cytometer having a plurality of fluorescence channels. Methods of interest utilize calibration sets of bead populations, wherein each bead population of the calibration set includes a different fluorophore attached to a surface thereof and the calibration set includes a number of bead populations that is less than the number of fluorescence channels of the flow cytometer. Flow cytometers, non-transitory computer-readable storage media, and kits including, e.g., calibration sets of bead populations for carrying out the subject methods are also provided.