Mechanical Oscillator Biosensing with Antinode Particle Traps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing biosensors using mechanical oscillators for detecting biomarkers face challenges such as fluid damping that degrades the sensor's detection limit and require complex functionalization, limiting their integration into microfluidic channels, and are unable to detect multiple targets simultaneously.
Innovation Solution
A detection system utilizing a mechanical oscillator with an integrated fluidic circuit that includes multiple traps positioned at vibration antinodes, allowing simultaneous detection of multiple targets by exciting the oscillator in different vibration modes and measuring resonance frequency shifts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the oscillator is immersed in the fluid being analyzed, then the sensor can detect targets in real-time, but the fluid damping degrades the mechanical quality factor and detection limit
Solution Approach 1:
The device is segmented into two distinct functional zones: a fluidic circuit for particle trapping and target interaction, and a vacuum cavity for high-Q oscillation. This spatial segmentation allows the oscillator to maintain high mechanical quality factor in vacuum while still enabling real-time detection through the integrated fluidic channel where targets are captured.
Solution Approach 2:
Functionalized particles serve as intermediaries between the target analytes in the fluid and the oscillator in the vacuum cavity. The particles are trapped in the fluidic circuit, capture targets, and their mass changes are detected by the oscillator, enabling indirect detection without direct fluid-oscillator contact.
2Measurement precision
If the oscillator is functionalized to ensure specificity of measurement, then target detection accuracy improves, but the integration into microfluidic channels becomes complex due to probe localization constraints
Solution Approach 1:
The functionalization complexity is extracted from the oscillator and transferred to separate functionalized particles. Instead of functionalizing the oscillator surface directly, the patent uses freely functionalizable particles that can be prepared independently and then trapped in the fluidic circuit, simplifying the overall device integration.
Solution Approach 2:
Functionalized particles act as intermediaries that carry the specificity function. These particles can be functionalized with various probes independently, and then introduced into the fluidic circuit, decoupling the specificity requirement from the oscillator structure and simplifying integration.
3Device complexity
If a single oscillator is used for detection, then the device structure is simplified, but the detection of multiple targets simultaneously is not enabled
Solution Approach 1:
A single oscillator is made multi-functional by trapping multiple different functionalized particles simultaneously in its fluidic circuit. Each particle type can be functionalized to detect different targets, allowing one oscillator to perform multiple detection functions through particle diversity rather than oscillator complexity.
Solution Approach 2:
The detection functionality is segmented across multiple particle types rather than requiring multiple oscillators. Each particle type is functionalized for a specific target, and all particles are trapped and detected by the single oscillator, achieving multi-target detection through functional segmentation at the particle level.
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
Enhances detection sensitivity and capability to detect multiple targets by maximizing the oscillator's frequency shift and surface area for target capture, achieving high-resolution mass detection of biomarkers like proteins, exosomes, and viruses.
Implementation Method 1
Gravimetric sensors are a prime example of such biosensors. These are based on the use of a mechanical oscillator or resonator, vibrating at its resonant frequency. Any target that attaches to the oscillator causes its mass to increase, which in turn lowers its resonant frequency by a shift proportional to the target's mass.
Implementation Method 2
A major drawback is the damping of the resonator's oscillation by the (viscous) fluid, degrading its mechanical quality factor
Implementation Method 3
By applying a pressure gradient between a fluidic inlet and outlet of the circuit, it is possible to control the fluid flow (its flow rate and direction), and therefore the passage of suspended particles through the SMR
Implementation Method 4
said first particle having an external surface functionalized by means of a first probe complementary to said first target and said second particle having an external surface functionalized by means of a second probe complementary to said second target
Data Source
Figure 1A~1B
Figure 2
Figure 3
AI summary
The invention relates to a method for detecting at least one target, implemented using a detection system which includes a measuring device (1_A, 1_B) comprising a mechanical oscillator (11_A, 11_B) and a fluidic circuit (10_A, 10_B) integrated into the oscillator and in which a fluid containing said at least one target to be detected is made to circulate, said oscillator (11_A, 11_B) being capable of being excited according to several vibration modes (M_1, M_2, M_3) and comprising on the fluidic network at least a first trap positioned on an antinode of a first vibration mode of the oscillator and a second trap positioned on an antinode of a second vibration mode of the oscillator, an antinode of vibration corresponding to a position in which the vibration amplitude goes from 80% to 100% of the maximum amplitude for the selected vibration mode.