Single Domain Nanoparticle EPR Imaging via Low-Field AC Fields
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current detection systems for magnetic resonance responses, particularly in MRI and FMR, face limitations in imaging biomedicine due to the need for reaction between particles and objects, and they struggle with achieving accurate and fast imaging without contrast agents, especially in low-frequency applications.
Innovation Solution
The use of single domain particles with diameters between 5 nm to 80 nm, subjected to a static magnetic field of less than 0.1 Tesla and RF energy to generate Electron Paramagnetic Resonance (EPR), allowing for detection and imaging without reaction, using continuous wave or pulsed radio frequency energy, and employing ultra-wide bandwidth pulses for improved signal penetration and contrast.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional MRI techniques are used, then imaging of human organs is achieved, but the technique requires high DC magnetic fields (1-3 Tesla) and narrow-band frequency ranges, limiting its applicability in biomedicine
Solution Approach 1:
The patent changes the operating parameters from conventional MRI's 1-3 Tesla DC fields and 10 kHz-1 MHz narrow-band frequencies to low-frequency AC magnetic fields (50 Hz-100 kHz) with broadband frequency ranges, enabling detection without requiring high magnetic fields while maintaining imaging capability
Solution Approach 2:
The patent replaces the mechanical NMR detection system requiring high DC magnetic fields with an electrical detection system using AC magnetic fields and broadband frequency analysis, substituting the physical constraints of nuclear magnetic resonance with electron paramagnetic resonance detection
2Power
If ferromagnetic resonance imaging is used, then stronger signals are obtained, but the technique is not suitable for biomedicine applications since the human body does not contain ferromagnetic properties
Solution Approach 1:
The patent introduces single domain particles as intermediary contrast agents that exhibit electron paramagnetic resonance at low frequencies. These particles serve as mediators between the AC magnetic field and the detection system, providing strong signals while being biocompatible and suitable for medical applications
Solution Approach 2:
The patent changes the detection target from ferromagnetic resonance (requiring ferromagnetic materials not present in the body) to electron paramagnetic resonance of single domain particles, operating at low frequencies (50 Hz-100 kHz) rather than the high frequencies required for conventional FMR
3Measurement precision
If single domain particles are used as contrast agents, then accurate and fast imaging is achieved, but the particles require reaction with the object being imaged
Solution Approach 1:
The patent enables single domain particles to self-generate detectable signals through their intrinsic electron paramagnetic resonance properties when exposed to AC magnetic fields. The particles do not require chemical reactions or external activation beyond the magnetic field application, allowing direct detection of their resonance responses
Solution Approach 2:
The patent replaces reaction-based detection mechanisms with direct electromagnetic detection of electron paramagnetic resonance signals, substituting chemical or biological reactions with physical electromagnetic field interactions that do not require particle-object reactions
4Reliability
If conventional detection systems are used, then magnetic resonance responses are detected, but the systems struggle with signal penetration and heat dissipation in biomedicine applications
Solution Approach 1:
The patent changes the operating frequency from conventional high-frequency MRI (10 kHz-1 MHz) to low-frequency AC magnetic fields (50 Hz-100 kHz). This parameter change reduces electromagnetic energy absorption by biological tissues, minimizing heat dissipation while improving signal penetration depth and detection reliability
Solution Approach 2:
The patent converts the potential harm of electromagnetic radiation into a benefit by using low-frequency AC fields that penetrate deeper into tissues with minimal heating. The low frequency reduces the harmful thermal effects while maintaining the ability to induce electron paramagnetic resonance in single domain particles
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
Enables accurate and fast imaging of objects with single domain particles, providing enhanced contrast and sensitivity, reducing heat dissipation and allowing for volumetric imaging, including 2D and 3D images, with improved signal penetration and minimal heat dissipation in biomedicine applications.
Implementation Method 1
applying a RF energy to the object at a frequency to generate Electron paramagnetic resonance (EPR) of the single domain particles, and detecting the EPR of the single domain particles
Data Source
AI summary
A method and system are disclosed for gathering information about an object including single domain particles which have a diameter in the range of about 5 to 80 nm. In one aspect, a method includes generating a static magnetic field of less than about 0.1 Tesla on the object and generating an RF energy, pulsed or continuous wave, so as to generate electron paramagnetic resonance of the single domain particles. The method also includes detecting the electron paramagnetic resonance of the single domain particles in the form of an image of the object. The single domain particles may have a predetermined diameter and a predetermined saturation magnetization and the applied magnetic field may be such that the single domain particles reach a magnetization being at least about 10% of the saturation magnetization. The method may be used for detecting tags in an object and for activating tags.