Shear Horizontal SAW Biosensor for Cardiac Troponin Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current high-sensitivity cardiac troponin (hs-cTn) assays for diagnosing myocardial infarction are limited by their non-portability, high costs, and requirement for experienced technical training, and they struggle with late clearance of biomarkers, making it difficult to diagnose recurrent myocardial infarction effectively.

Innovation Solution

A handheld, portable shear horizontal (SH) surface acoustic wave (SAW) sensor system with functionalized detection lanes that uses a wet-dry method to concentrate samples, allowing for specific antibody-antigen interactions and enabling measurements at concentrations as low as 10 pg/ml without the need for extensive technical training, and allows for multiplexed biomarker measurements and simultaneous electrocardiogram (EKG) testing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional high-sensitivity cardiac troponin assays are used, then detection sensitivity is improved, but portability and ease of operation deteriorate

Engineering Contradiction:
Improvedetection sensitivityVSAvoidportability and ease of operation
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The patent replaces complex mechanical laboratory equipment with a portable SAW sensor system that uses surface acoustic wave technology. The sensor detects troponin through immunochemical reactions on a piezoelectric substrate, eliminating the need for large-scale laboratory machinery while maintaining high detection sensitivity.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the detection parameter from traditional bulk liquid analysis to surface-constrained immunochemical reactions. By functionalizing the SAW sensor surface with antibodies and detecting bound troponin through acoustic wave propagation changes, the system achieves high sensitivity in a portable format.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If conventional laboratory-based hs-cTn assays are used, then measurement accuracy is improved, but device complexity and cost worsen

Engineering Contradiction:
Improvemeasurement accuracyVSAvoiddevice complexity and cost
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts the essential detection function from complex laboratory assays by isolating the immunochemical reaction and acoustic detection components. The SAW sensor integrates the antibody-functionalized surface and acoustic wave detection into a single compact device, removing unnecessary laboratory infrastructure.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent creates a universal detection platform where the same SAW sensor technology can detect multiple biomarkers by changing the functionalization layer. This multi-functional approach reduces overall system complexity compared to having separate specialized tests for each biomarker.

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

3Measurement precision

If troponin measurements are taken sequentially to address late clearance, then diagnostic accuracy for recurrent infarction is improved, but analysis time worsens

Engineering Contradiction:
Improvediagnostic accuracyVSAvoidanalysis time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent enables continuous or rapid sequential measurements by maintaining the SAW sensor in a ready state with functionalized surfaces. The portable design allows repeated sampling and rapid re-measurement without requiring re-preparation of reagents or equipment, facilitating continuous monitoring for recurrent infarction.

Inventive Principle:
Principle #20Continuity of useful action

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

The system provides rapid, reliable, and sensitive detection of cardiac troponin I and other biomarkers, reducing analysis time to less than 10 minutes and increasing diagnostic confidence with accurate measurements across a wide dynamic range, from 2 pg/ml to 24 µg/ml, facilitating bedside diagnostics and reducing the risk of misdiagnosis.

Implementation Method 1

a shear horizontal (SH) surface acoustic wave (SAW) biosensor to detect the binding of target antigens to specific antibodies that are immobilized on a piezo-electric substrate

Methodology Applied
Scientific EffectSurface acoustic wave: Surface Acoustic Wave

Implementation Method 2

specific antibodies that are immobilized on a piezo-electric substrate (lithium tantalite)

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 3

removing fluid from the functionalized detection lane to concentrate the sample in the functionalized detection lane

Methodology Applied
Scientific EffectEvaporation: Evaporation

Data Source

PatentEP3948255B1Detection of cardiac troponin or biological markers via shear horizontal surface acoustic wave biosensor using a wet-dry bioanalytical technique
Publication Date: 2023.06.07 AUTONOMOUS MEDICAL DEVICES INC
  • EP3948255B1 patent drawingFigure 1~2
  • EP3948255B1 patent drawingFigure 3~4
  • EP3948255B1 patent drawingFigure 5~6

AI summary

The illustrated embodiments include a method of operating a SAW sensor to detect a sample in a fluid which includes the steps of: providing a SAW sensor with a functionalized detection lane in a handheld, portable assay and sensor system; maintaining the functionalized detection lane of the SAW sensor dry until the sample is fluidicly disposed in the detection lane; fluidicly disposing the sample in the functionalized detection lane; removing fluid the functionalized detection lane to concentrate the sample in the functionalized detection lane to increase the probability of a specific antibody-antigen interaction; washing the functionalized detection lane so that substantially only the specific antigen-antibody interaction remains in the functionalized detection lane; removing fluid from the functionalized detection lane again; and measuring concentration of the sample while the functionalized detection lane is fluid-free.