University of Illinois

Richard L Magin

Jonathan V Sweedler

Timothy L Peck

Andrew G Webb

Steven J Franke

Carson Ingo

Dean L Olson

Nian Wu

Ronald D Boesch

Disclosed herein is an example method and system for characterizing a biological structure in terms of bio-markers derived from diffusion weighted magnetic resonance imaging (DWI) data of biologic material. A first set of DWI data may be obtained using a fixed diffusion encoding gradient and a plurality of diffusion time resolutions, and a second set of DWI data may be obtained using a fixed diffusion time resolution and a plurality of diffusion encoding gradients. The first and second sets may be analytically fit with a fractional power-law diffusion model parameterized by fractional exponents each uniquely corresponding to one of a plurality of bio-markers of the biologic material. Fractional exponents may be determined from the analytical fitting of the first and second sets of DWI data, and an image of the biologic material may be generated and displayed.

Fractional order and entropy bio-markers for biological tissue in diffusion weighted magnetic resonance imaging

The present invention provides and NMR apparatus comprising an analyte sample holder having a containment region that holds a volume of less than about 1 microliters of the analyte sample, a coil, which encloses the containment region of the analyte sample holder and the analyte sample contained therein, the coil operatively associated with the analyte sample contained in the containment region of the analyte sample holder such that the coil can transmit and/or receive energy from the analyte sample in the containment region of the analyte sample holder, and a magnet to provide a static magnetic field in which the coil and the analyte sample in the containment region of the analyte sample holder are located, wherein the coil and the magnet provide for the obtainment of an NMR spectrum having a spectral line width resolution of less than about 0.1 parts per million.

Microcoil based micro-NMR spectrometer and method

The present invention provides an NMR apparatus comprising an analyte sample holder having a containment region that holds a volume of less than about 10 microliters of the analyte sample, a microcoil, which encloses the containment region of the analyte sample holder and the analyte sample contained therein, the microcoil having an inside dimension of less than about 1 mm, and the microcoil operatively associated with the analyte sample contained in the containment region of the analyte sample holder such that the microcoil can transmit and/or receive energy from the analyte sample in the containment region of the analyte sample holder, and a magnet having a mass less than about 50 kg, the magnet positioned about the microcoil and the analyte sample in the containment region of the analyte sample holder to provide a static magnetic field in which the microcoil and the analyte sample in the containment region of the analyte sample holder are located, wherein the microcoil and the magnet provide for the obtainment of an NMR spectrum. The present invention also provides a method of analysis and elucidation of the chemical structure of an analyte using NMR, the method comprising providing an analyte sample that has a volume of less than about 10 microliters, enclosing the analyte sample in a microcoil, generating a static magnetic field about the analyte sample using a magnet, transmitting energy to the analyte sample to excite the sample from its equilibrium state to its excited state, detecting the energy emitted from the analyte sample when the sample relaxes from its excited state to its equilibrium state using the microcoil, and analyzing and graphically displaying the detected energy as a time or frequency domain spectrum.

An apparatus and method for compensation of magnetic susceptibility variation in NMR microspectroscopy detection microcoils. NMR detection microcoils are formed with side-by-side windings in order to approximate a uniform cylindrical sheet coil. The wire may have a thin layer of insulation in order to prevent shorting between adjacent turns, or (if the wire diameter is small enough) uninsulated wire may be wound with the adjacent turns touching without fear of shorting between coil turns. Additionally, a susceptibility matching medium, such as a perfluorinated hydrocarbon, may be placed around the microcoil to minimize susceptibility-induced variations in the B.sub.0 magnetic field.

Apparatus and method for compensation of magnetic susceptibility

A method and apparatus for structural elucidation and determination of a nanoliter size sample of analyte. The method includes separating the analyte using a microseparation technique and then substantially simultaneously analyzing or detecting the sample using a nuclear magnetic resonance (NMR) spectrometer. The apparatus includes an RF microcoil positioned for operable communication with a capillary member of the microseparation system and the NMR spectrometer to provide enhanced sensitivity and improved signal-to-noise ratio of the NMR spectrometer necessary to accurately analyze or detect nanoliter size samples.

Method and apparatus for NMR spectroscopy of nanoliter volume samples

A continuous microstrip phase shifter suitable for use in a phased array microwave hyperthermia system operating at 915 MHz is provided. The phase shifter utilizes a three dB quadrature hybrid coupler in conjunction with microstrip lines to change the phase of a transmitted wave. The phase change is introduced through the reflection ports of the coupler which are loaded with identical parallel resonant circuits. An abrupt junction varactor capacitance in parallel with a distributed inductance forms a voltage-tunable resonant circuit. The resonant element values are chosen to give a specified continuous phase variation with minimum transmission loss. This is accomplished without additional microwave circuit elements.

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Urbana, IL, United States of America

Richard L Magin