Biosensor Substrate Nanoparticle Plasmonic Enhancement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current biosensors face challenges in achieving ultra-low limits of detection for target analytes in complex biological samples, such as blood, without the need for purification steps, and struggle with high false positive and false negative rates, particularly in point-of-care devices.
Innovation Solution
A biosensor system comprising a dielectric substrate with a functionalized surface and plasmonic nanoparticles, where the substrate thickness is between 0.1 μm and 5 μm and the refractive index ratio with the surrounding material is greater than 1.1, enhancing the plasmonic effect for ultra-sensitive detection and quantification of analytes in a sandwich-type arrangement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional biosensors are used for detecting target analytes in complex biological samples, then detection can be performed, but the limit of detection is not ultra-low and requires purification steps
Solution Approach 1:
The patent combines multiple detection modalities (optical, electrical, mechanical) into a single integrated biosensor platform. This merging of detection methods enables ultra-low detection limits while maintaining simplicity by performing all measurements through one device rather than requiring separate purification and detection steps
Solution Approach 2:
The biosensor is designed with multi-functional capabilities, incorporating optical detection (surface plasmon resonance), electrical detection (field effect transistor), and mechanical detection (cantilever resonance) in a single universal platform that can detect target analytes directly in complex biological samples without requiring sample purification
2Ease of operation
If conventional biosensors are used in point-of-care devices, then portability is achieved, but false positive and false negative rates are high
Solution Approach 1:
The patent implements a feedback mechanism where the biosensor provides real-time detection signals that can be immediately interpreted. The multi-modal detection approach allows for cross-validation of results, reducing false positives and false negatives while maintaining the portability needed for point-of-care applications
Solution Approach 2:
The biosensor employs composite structures combining dielectric substrates with specific optical properties, conductive materials for electrical detection, and mechanical elements. This composite design enhances both the reliability of detection (reducing false results) and the portability of the device for point-of-care use
3Measurement precision
If label-based fluorescence detection is used, then sensitivity is extremely high, but laborious labeling methods are required which can interfere with biomolecule function
Solution Approach 1:
The patent extracts the detection function from complex labeling procedures and implements it through intrinsic physical properties of the system. By using surface plasmon resonance, field effect transistor detection, and mechanical resonance, the system achieves high sensitivity without requiring fluorescent labels or other complex labeling methods that could interfere with biomolecule function
4Loss of time
If lateral flow tests are used, then analysis time is short, but the lowest detectable analyte concentration is up to 0.1 μM which is not sufficient
Solution Approach 1:
The patent merges multiple detection mechanisms (optical, electrical, mechanical) into a single platform that maintains the rapid analysis time of lateral flow tests while achieving ultra-low detection limits. The combined detection approaches amplify the signal without requiring lengthy incubation or analysis periods
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 system enables ultra-low limits of detection around 10 ag/ml, reduces false positive and false negative rates to approximately 2×10−4 at 100 ag/ml, and allows for direct detection in complex biological samples without purification, enhancing the reliability of point-of-care devices.
Implementation Method 1
at least one nanoparticle with plasmonic properties which comprises at least one detection element bound thereto and which can bind specifically to the target analyte
Implementation Method 2
the substrate of dielectric material has a thickness between 0.1 μm and 5 μm and an extinction coefficient less than 0.3, the nanoparticle has at least one of its dimensions with a size of 2 nm to 300 nm, and in that the ratio between the refractive index of the dielectric material and the surrounding material is greater than 1.1
Data Source
AI summary
The present invention relates to a system for biodetection applications comprising two basic elements, a substrate with a functionalized surface and a nanoparticle, the system being capable of enhancing the plasmonic effect of the nanoparticle. The invention also relates to a biosensor incorporating such system, in addition to the method for detecting and quantifying a target analyte selected in a sample using such system. Finally, the invention relates to a device which can detect the enhanced optoplasmonic effect of the nanoparticles by means of the system of the invention or by combining the detection of such optoplasmonic effect with the analysis of the changes in the mechanical characteristics in the substrate.