Self-referencing LSPR Sensor with Porous Membrane
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LSPR sensors suffer from low sensitivity and inadequate detection limits due to long incubation times required to reach chemical equilibrium and weak reflectance LSPR signals, which are not suitable for point-of-care diagnostics.
Innovation Solution
A self-referencing sensor using a substantially transparent, porous membrane with immobilized metal nanoparticles functionalized with capture molecules, allowing for real-time detection of target chemicals by distinguishing between specific binding signals and non-specific signal changes through distinct LSPR signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional LSPR sensors with planar surfaces are used, then the sensor structure is simple, but the sensitivity is low and detection limits are inadequate
Solution Approach 1:
The patent employs a porous membrane substrate with controlled pore sizes (e.g., 20-200 nm) to immobilize metal nanoparticles. This porous structure dramatically increases the surface area available for nanoparticle attachment and capture molecule immobilization, thereby enhancing sensitivity and lowering detection limits without requiring complex device architecture.
Solution Approach 2:
The invention transitions from traditional two-dimensional planar sensor surfaces to three-dimensional porous membrane structures. This dimensional change allows nanoparticles to be distributed throughout the membrane volume, creating multiple sensing interfaces and significantly improving detection sensitivity while maintaining structural simplicity.
2Reliability
If long incubation times are used to reach chemical equilibrium, then binding completeness is improved, but productivity and real-time detection capability deteriorate
Solution Approach 1:
The porous membrane structure creates localized high-concentration zones of capture molecules within the pores. This localized concentration effect enhances the probability of target-analyte encounters, accelerating binding kinetics and reducing the time required to reach chemical equilibrium while maintaining complete binding.
Solution Approach 2:
The sensor enables continuous real-time monitoring of binding events through sustained LSPR signal measurement. The system maintains continuous interaction between flowing sample and immobilized capture molecules, allowing productivity improvement without sacrificing binding completeness through extended incubation.
3Ease of operation
If reflectance LSPR spectroscopy is used for detection, then the measurement setup is straightforward, but the signal strength is weak
Solution Approach 1:
The porous membrane structure enhances LSPR signal strength by providing a three-dimensional array of metal nanoparticles that collectively generate stronger plasmonic responses. The porous architecture increases light-nanoparticle interaction volume and improves signal intensity while maintaining compatibility with standard reflectance spectroscopy setups.
4Measurement precision
If labeled capture molecules are used for detection, then binding events can be observed, but steric hindrance and device complexity increase
Solution Approach 1:
The metal nanoparticles serve as self-sufficient transducers that generate detectable LSPR signals inherently, without requiring external labels on capture molecules. The nanoparticles' own optical properties enable direct detection of binding events, eliminating the need for fluorescent or other types of labels and their associated complexity.
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 solution reduces diffusion time and enhances sensitivity, achieving improved detection limits and enabling real-time, label-free assays for chemical detection, which is crucial for point-of-care diagnostics and biomolecular interaction analysis.
Implementation Method 1
Metal nanoparticle transducers can be used to monitor binding events in real time without additional labels through a phenomenon known as localized surface plasmon resonance (LSPR). LSPR is a phenomenon associated with noble metal nanoparticles that creates sharp spectral absorbance and scattering peaks and produces strong electromagnetic near-field enhancements.
Implementation Method 2
The sensor comprises a substantially transparent, porous membrane having nanoparticles such as metal nanoparticles immobilized on the surface of its pores... reduces diffusion time and enhances sensitivity
Data Source
AI summary
Provided herein is a sensing apparatus comprising, at least one LSPR light source, at least one detector, and at least one sensor for LSPR detection of a target chemical. The sensor comprises a substantially transparent, porous membrane having nanoparticles immobilized on the surface of its pores, the nanoparticles being functionalized with one or more capture molecules. There is further provided a self-referencing sensor for distinguishing non-specific signals from analyte binding signals. The self-referencing sensor comprising one or more nanoparticles having at least two distinct LSPR signals.