38 results about "Dynamic nuclear polarisation" patented technology

The invention relates to carbon-13 enriched fullerene and carbon nanotube (CNT) compositions for improved magnetic resonance imaging (“MRI”). The invention also relates to a dynamic nuclear polarization (DNP) method of MRI utilizing the carbon-13 enriched fullerene and CNTs of the invention.

A method for the preparation of a sample comprising highly polarized nuclear spins is proposed, comprising at least the following steps:

• • a) provision of molecules with 1,2-dione structural units and/or molecules with 2,5-diene-1,4-dione structural units in the solid state;
  • b) generation of radicals from these molecules by photo induced electron transfer by a first electromagnetic irradiation in the visible or ultraviolet frequency range in the solid state;
  • c) dynamic nuclear polarization in the presence of a magnetic field in the solid state by applying a second electromagnetic irradiation with a frequency adapted to transfer spin polarization from the electrons to the nuclear spins leading to a highly polarized state thereof. Furthermore uses of correspondingly prepared samples for NMR, MRS and MRI experiments are proposed.

A rapid cycle dynamic nuclear polarization (DNP) NMR apparatus comprises (i) a cooling unit, configured to cool a sample in a capillary, (b) a DNP polarization unit configured to polarize the sample in the capillary, (c) a stripline-based NMR detector comprising a stripline for NMR analysis of the sample in the capillary, (d) a transport unit configured to guide the capillary from the DNP polarization unit to the stripline of stripline-based NMR detector; and (e) a heating unit configured to heat the sample in the capillary before analysis of the sample by the stripline-based NMR detector. Fast (1D-3D) NMR measurements with high resolution may be obtained.

Compositions and methods useful in connection with magnetic resonance imaging are provided. Metabolites hyperpolarized by dynamic nuclear polarization are used as reporter molecules in nuclear magnetic resonance (“NMR”) spectroscopy to study metabolic pathways and diagnose disease states. The reporter molecules include hyperpolarized glutamine and hyperpolarized acetate. The invention includes the reporter molecules, compositions including the reporter molecules in pharmaceutically acceptable carriers, methods for studying metabolic pathways that include introducing one or more of the reporter molecules to a mammalian subject and imaging a target substance using NMR spectroscopy, and kits useful in studying metabolic pathways that incorporate one or more of the reporter molecules and instructions for their use.

The invention discloses a parallel magnetic resonance method based on dynamical nuclear polarization multinuclear simultaneous enhancement. An electronic-nuclear spin system is located in a magnetic field with the strength of B0; the electronic-nuclear spin system is irradiated through microwaves; microwave irradiation is stopped; nuclear magnetic resonance pulses are applied; enhancement signals of atomic nucleuses corresponding to all channels are collected; enhancement spectrograms or images are reestablished and obtained. Under the condition of saturated electrons, signal enhancement of multiple atomic nucleuses can be obtained at the same time. The mutual relation between different atomic nucleuses and electrons and the mutual relation between the atomic nucleuses can be obtained at the same time. Under the condition of a single saturated electron, enhancement images of different atomic nucleuses can be obtained at the same time, and the two-dimensional and multi-dimensional spectrograms of different atomic nucleuses can be obtained.

A method and apparatus are provided for treating hydrated material in a fluid that contains water in which a stable nitroxide is attached to the hydrated material. A dynamic nuclear polarization process (DNP) is conducted on the hydrated material whereby to hyperpolarize the water. A polarization cell contains the hydrated material to obtain hyperpolarized water free from the nitroxide. The dynamic nuclear polarization process is conducted using components comprising a tunable, solid state high power X-band driver and an X-band resonator for microwave transmission to the hydrated material. The components can also include a radio-frequency nuclear magnetic resonance probe, a permanent magnet formed to receive the hydrated material, a portable nuclear magnetic resonance spectrometer, and an electron spin resonance detector. The components can be sized to be portable, and include electrical input and output and a lap-size hard-case with access to the electrical input and output.

We describe a method for use in enhancing MRI signals and increasing the sensitivity of NMR spectroscopy. The method involves the use of dynamic nuclear polarization (DNP) in which the polarizing agents are sequestered at the interface between two phases a sample phase, and a polarizing phase in such a way that the polarizing agent can be easily removed from the sample prior to analysis. The method produces much efficiency for sample manipulation, and the polarization process. In at least one embodiment the hyper-polarization can be repeated so as to allow the accumulation of spectra of the same material for further increasing the signal to noise ratio. The method also allows a discernment of which peaks in an NMR spectrum of a mixture belong to each individual component.

The invention relates to a dynamic nuclear polarization apparatus (116) for continuous provision of hyperpolarized samples (114) comprising dynamically nuclear polarized nuclear spins, the apparatus (116) comprising a polarization region (106) for polarization of said nuclear spins resulting in said hyperpolarized samples, wherein the apparatus (116) further comprises: a cryostat (102) for cooling the samples (114) in the polarization region (106), a magnet (100) for providing a magnetic field to the cooled samples in the polarization region (106), a radiation source (112) for concurrently to the magnetic field provision providing a nuclear polarizing radiation to the polarization region (106) for receiving the hyperpolarized samples, a sample transport system (104) for continuously receiving unpolarized samples (114), transporting the unpolarized samples to the polarization region (106) for nuclear spin polarization and providing the resulting hyperpolarized samples (114).

Spin labeled ice binding compounds (IBCs) including ice binding proteins (IBPs), also called antifreeze proteins (AFPs) and their analogs are exploited to carry the paramagnetic centers for dynamic nuclear polarization (DNP), for enhancing nuclear magnetic resonance (NMR) signal intensities. Use of spin labeled IBCs to perform DNP exploits the IBCs' ability to homogeneously distribute the paramagnetic centers in frozen water solution at low temperature, leading to high DNP efficiency. Other advantages of using spin labeled IBCs include: (1) ability to cryo-protect biological samples; (2) the relative positions and orientations of the spin labeling groups in an IBC may also be cryo-preserved; (3) positions and orientations of spin labeling groups to an IBC can be selected with great freedom and without technical barrier to making multiple spin labels in an IBC; and (4) water solubilities of spin labeled IBCs are potentially high, enabling use of a solvent that is primarily water for DNP at low temperatures.

A method for preparing a sample for dynamic nuclear polarization which comprises submitting a solid substrate to a milling process in the presence of a polarizing agent at a temperature lower than the glass-transition temperature (Tg) of said substrate. Preferably said substrate may be in crystalline form.

The invention concerns a dinitroxide biradical compound, in which the two nitroxide units are held by a rigid linkage, of general formula (I) in which—A is a carbon, an ammonium or a phosphonium, each of A₁ to A6 is selected separately from the group comprising a single bond, O, N, N(O), S, S(O), SO2, C(O), a (C1-C4) alkyl chain, Z1 and Z2 are chosen from RI and R2 in combination, such that there is always, in the combination, at least one R2 group that needs to be substituted by an R3 group, RI is an H, a (C6-C18) aryl or a (C3-C18) heteroaryl, R2 a (C1-C17) alkyl chain, a (C1-C17) alkenyl chain, a (C1-C17) alkynyl chain, a (C4-C17) cycloalkyl, a (C4-C17) heterocycloalkyl, a (C6-C18) aryl, a (C3-C18) heteroaryl, R3 is a (C1-C17) alkyl chain, a (C1-C17) alkenyl chain, a (C1-C17) alkynyl chain, a (C4-C17) cycloalkyl, a (C4-C17) heterocycloalkyl, a (C6-C18) aryl, a (C3-C18) heteroaryl, an ether —OR, an ester —C(O)O—R (in which R is any hydrocarbon radical), an azide, and in which, when Z1 and Z2 are combined together with the same carbon atom of the nitroxide ring to which they are bonded, they form a spirocycloalkyl or a spiroheterocycloalkyl substituted by R3.

A composition containing (1) a porous material and (2) a polarization source for dynamic nuclear polarization containing a molecule capable of being in an excited triplet state. According to the composition, a dynamic nuclear polarization system that has a long spin-lattice relaxation time and can readily introduce the polarization object thereto can be provided.

A cooling system is provided. The cooling system is associated with a dynamic nuclear polarization system and configured to cool a sample to a temperature suitable for dynamic nuclear polarization to be carried out on the sample while the sample is in the cooling system. The cooling system includes a cryogenic chamber that includes a cryogenic fluid. The cooling system also includes a removable sample sleeve insertable within a portion of the cryogenic chamber. The removable sample sleeve is configured to define a sample path for the sample within the cryogenic chamber that is isolated from other parts of the cooling system.

The invention provides a noise suppression system and method suitable for proton magnetic precession signals. A dynamic nuclear polarization sensor receives excitation signals sent by an excitation circuit; proton magnetic precession signals are sensed; the signals are transmitted to a tuning circuit; the tuning circuit tunes the signals and transmits the tuned signals to an amplification circuit;the amplification circuit amplifies the signals; a narrowband filter performs band-pass filtering on the amplified signals to remove noises outside a central frequency band, and transmits the signalsto a comparison circuit; the comparison circuit shapes the signals processed by the narrow-band filter into square waves and transmits the signals to an FPGA; the FPGA performs later-stage signal processing; a collector is connected with a controller and performs data acquisition and processing; the controller is connected with the excitation circuit and controls the start and stop of the excitation signals; the controller is connected with the FPGA; the FPGA performs frequency measurement on the proton magnetic precession signals which have been shaped into the square waves and converts a measured frequency value into a magnetic field value; and the controller is connected with the narrow-band filter and adjusts the narrow-band center frequency of the narrow-band filter.

A method for measuring oil-water distribution using DNP-MRI, comprising adding a free radical for DNP enhanced NMR signal of a water phase or an oil phase in a sample containing oil and water; performing an MRI experiment on the sample, and collecting an MRI image of the sample without DNP enhancement; applying microwave excitation for DNP-MRI experiment under the same MRI experiment condition as step 2, and collecting an MRI image of the sample after DNP enhancement; and comparing the MRI image after DNP enhancement with the MRI image without DNP enhancement. In the MRI image with DNP enhancement, an area with enhanced MRI signal intensity is a selectively enhanced fluid phase distribution area, and an area without obviously changed MRI signal intensity is a non-selectively enhanced fluid phase distribution area. The method is simple, convenient to operate, short in measurement time, and high in measurement efficiency.

The invention discloses a double-frequency DNP probe system for a dynamic nuclear polarization system and an assembling method thereof, and belongs to the technical field of nuclear magnetic resonance. A first bottom plate and a second bottom plate are mainly disposed for cooperative use to the inner wall surface of an inner hole in a solenoid for radio frequency resonance to form a Terahertz resonant cavity, thus realizing dual resonance of a radio frequency band and a Terahertz frequency band, effectively reducing the volume of the DNP probe and having good applicability.

A method for separating oil-water two-phase NMR signals by using dynamic nuclear polarization comprising: using a combination of a non-selective free radical and a selective relaxation reagent to selectively enhance an NMR signal of an oil phase or a water phase, the relaxation reagent being capable of selectively suppressing dynamic polarization enhancement of the water phase or oil phase, thus achieving the polarization enhancement of a single fluid phase in the mixed fluid phases and realizing separation of the two-phase signals; or using a selective free radical to selectively enhance the NMR signal of the oil phase or the water phase, thus achieving the polarization enhancement of a single fluid phase in the mixed fluid phases and realizing separation of the oil-water two-phase NMR signals. The method is simple and easy to operate, has a short test time, and can efficiently separate NMR signals of oil and water phases.