Electrochemical Factor Xa Inhibitor Detection in Whole Blood
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for determining factor Xa inhibitors in blood samples are labor-intensive, require complex equipment, and often necessitate complicated sample preparation, making them unsuitable for rapid and reliable monitoring, especially in decentralized settings like intensive care units.
Innovation Solution
A method involving a blood sample contacted with a factor X reagent and an activator reagent to convert factor X into factor Xa, followed by an electrochemical measurement using a peptidic thrombin substrate to determine the factor Xa inhibitor levels, allowing for direct analysis in whole blood without extensive sample preparation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If global coagulation assays (aPTT, TCT, ACT) are used to monitor heparin therapy, then the monitoring can be performed with standard equipment, but the results are unspecific and require complex experimental procedures with specially trained personnel
Solution Approach 1:
The invention introduces a specific factor Xa substrate as an intermediary that mediates between the blood sample and the measurement system. This substrate specifically reacts with factor Xa, providing a direct and specific measurement of factor Xa activity rather than global coagulation parameters. The substrate acts as a bridge that translates the biological activity into a measurable signal with high specificity.
Solution Approach 2:
The invention replaces complex mechanical/coagulation-based assays (aPTT, TCT, ACT) with a simplified electrochemical detection system. Instead of measuring clot formation time or other mechanical coagulation parameters, the system uses electrochemical sensors to directly detect factor Xa activity, substituting a simpler measurement mechanism for the complex coagulation cascade assays.
2Measurement precision
If chromogenic factor Xa tests are used to specifically determine factor Xa activity, then the specificity is improved, but the tests require complicated sample preparation and separation of plasma
Solution Approach 1:
The invention extracts only the essential measurement function from the complex chromogenic test system. Instead of requiring complete plasma separation and multiple preparation steps, the test element extracts and captures factor Xa directly from whole blood using a specific substrate, eliminating the need for plasma separation while maintaining measurement specificity.
Solution Approach 2:
The test element is designed to be self-sufficient, requiring no external plasma separation or complex sample preparation. The reagents and substrate are integrated into the test element itself, which automatically performs the measurement function when applied to the blood sample, making the system self-service and eliminating manual preparation steps.
3Device complexity
If electrochemical test elements with dry chemistry are used, then the device complexity and labor requirements are reduced, but the measurement precision and reliability must be maintained
Solution Approach 1:
The invention changes the physical state of the reagents from liquid to dry form, and the measurement mode from optical to electrochemical. This parameter change allows the test element to be stored and handled in a stable dry state, then activated upon contact with blood, maintaining reliability while simplifying the device and eliminating the need for complex liquid handling systems.
Solution Approach 2:
The invention replaces optical detection systems with electrochemical detection. This substitution simplifies the measurement system by using electrical signals instead of optical paths, reducing device complexity while maintaining or improving measurement reliability through direct electrochemical detection of the reaction products.
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 simplifies the determination of factor Xa inhibitors, providing accurate and specific results with reduced labor and equipment requirements, enabling rapid and reliable monitoring in whole blood samples.
Implementation Method 1
measuring an electrochemical signal associated with the amount or activity of the electrogenic substance
Data Source
AI summary
Methods and devices for determining factor Xa inhibitors, in particular heparins and fractionated or low-molecular-weight heparins, as well as direct factor Xa inhibitors in blood samples. The methods include contacting a blood sample with a detection reagent that contains at least one thrombin substrate having a peptide residue that can be cleaved by thrombin and is amidically bound via the carboxyl end to an electrogenic substance, and with a known amount of factor X reagent and an activator reagent which induces the conversion of factor X into factor Xa. Subsequently, in a second step, the amount or activity of the electrogenic substance that is cleaved from the thrombin substrate by the factor Xa-mediated thrombin activation and/or the time course thereof is determined as the measurement signal using electrochemical methods. In a third step, the amount of the factor Xa inhibitor in the sample of the blood to be analyzed or a measured quantity that correlates therewith, in particular a clotting time that correlates therewith, is determined on the basis of this measurement signal.