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  • Unconventional Magnetic Resonance Techniques | Pines Lab
    determination of proteins involved in a wide range of disorders and human diseases Learn more Pines Lab About Research People Publications Seminars Photo Gallery Sign In Unconventional Magnetic Resonance Techniques About the Lab Pines research program involves the development of new nuclear magnetic resonance NMR and magnetic resonance imaging MRI methods and their application to exemplary problems spanning chemistry materials science and biomedicine His laboratory has introduced NMR techniques that make it possible to probe the structure dynamics and function of materials in the solid state His current research interests involve novel approaches to spin polarization detection molecular sensing and miniaturization More About Alex Pines Alexander Pines was born in 1945 He grew up in Rhodesia now Zimbabwe where his lifelong passion for science music and chess was fostered He then went to Israel to study mathematics and chemistry at the Hebrew University of Jerusalem graduating with a B Sc in 1967 In 1968 Alex came to MIT where he obtained his Ph D in chemical physics in 1972 and joined the Berkeley Faculty in the same year He was promoted to Associate Professor in 1975 and to Professor in 1980 He is currently the Glenn T Seaborg Professor of Chemistry at Berkeley a Senior Scientist in the Materials Sciences Division of the Lawrence Berkeley National Laboratory and a Faculty Affiliate at QB3 the California Institute for Quantitative Biomedical Research More About Our People The Pines Lab is made up of a diverse group of graduate students from the UC Berkeley Department of Chemistry Department of Physics Department of Bioengineering and Biophysics Graduate Group More Current Pinenuts Alumni Sign In History of Innovation Pines is a pioneer in the development and applications of nuclear magnetic resonance NMR spectroscopy In his early work he demonstrated time reversal of dipole dipole couplings

    Original URL path: https://pines.berkeley.edu/ (2015-04-17)
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  • Optically Detected NMR | Pines Lab
    centers have been used to detect small ensembles of nuclear spins producing nT fields and for the high resolution mapping of magnetic field gradients 7 History Optically detected magnetic resonance has been explored in the lab since the early 1970 s when Breiland Harris and Pines first demonstrated optical detection of electron precession and electron spin echoes by monitoring the phosphorecence of excited triplet states 8 ODMR has since been used to study the polarization of nuclear spins in semiconductors and also for direct detection of local magnetic fields 9 More recently with alkali vapor magnetometers we have obtained relaxometry measurements at earth s field and have obtained zero field NMR spectra via optical detection methods 10 Detection of an NMR signal with an alkali vapor magnetometer was first demonstrated at Princeton by Savukov and Romalis 11 Here they detected an NMR signal from water and also detected less than 10 13 Xe atoms Since then this work has been additionally explored by many others including the Pines lab In collaboration with the John Kitching NIST these magnetometers have been miniaturized and used to remotely detect NMR 12 Most recently we have obtained spectra of J couplings at zero field spectra that provide rich amount of information about the nuclear couplings in molecules Due to their favorable spin properties long coherence times ms optically addressable spin states NV centers have been studied extensively in the past few decades The luminsecent properties and associated EPR spectra of NV centers were first explored by Davies and Hammer 13 Manson et al characterized the NV center more throughly gaining insight in the electronic energy levels and rates associated with its polarization 14 Using NV as a highly sensitive magnetometer and high resolution magnetic field sensor was first proposed by Taylor in 2008 15 and later demonstrated by Rugar 1 and Acosta 17 The Pines lab has recently characterized the magnetic field detection bandwidth of and ensemble of NVs as well as their use as polarizing agents for NMR Current Work Current work involves the use of alkali vapor magnetometers for ultra low field NMR and zero field measurements miniaturization of alkali vapor magnetometers for portable NMR and remote detection of nuclear spins using ensembles of nitrogen vacancy centers for high resolution microfluidics applications People Involved Claudia Avalos Daniel Kennedy Jonathan King Anna Parker Scott Seltzer Chang Shin Hai Jing Wang Keunhong Jeong Collaborators Dmitry Budker UC Berkeley Physics John Kitching NIST Jeff Reimer UC Berkeley Chemical Engineering Thomas Schenkel LBNL ALS References 1 H J Mamin M Kim M H Sherwood C T Rettner K Ohno D D Awschalom D Rugar Nanoscale Nuclear Magnetic Resonance with a Nitrogen Vacancy Spin Sensor Science 339 6119 557 560 2013 2 J W Blanchard M P Ledbetter T Theis M C Butler D Budker A Pines High resolution Zero field NMR J spectroscopy of Aromatic Compounds Journal of the American Chemical Society 135 3607 3612 2013 3 T Staudacher F Shi S Pezzagna J Meijer J

    Original URL path: https://pines.berkeley.edu/research/optical_detection (2015-04-17)
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  • Remote Detection | Pines Lab
    magnet equipped with magnetic field gradients and flowing the sensor medium e g 129 Xe H 2 O etc through the sample As the sensor interacts with the sample an optimized induction coil is use to apply radiofrequency pulses and gradients to select a region of the sample and encode information in magnetization The sensing medium then travels to a separately optimized detector where the information can be recovered A travel curve shows how long it takes for the sensing medium to travel to the detection coil More complex pulse sequences may be implemented to recover spectral or spatial information about the sample or its environment For instance pulse sequences may be implemented to determine the geometry of the fluid s environment or to look at the flow properties of the fluid itself History Remote detection NMR is particularly useful is applications which already involve the movement of information from one location in space to another To this end remote detection has been essential to studies involving hyperpolarized 129 Xe gas flowing through sandstone rock 2 aerogels 3 and microfluidic chips 4 5 We have studied the flow and mixing of liquids such as water and ethanol in microfluidic devices 6 and high pressure liquid chromatography HPLC columns 7 Current Work Current work in our lab involves the application of remote detection techniques to the development of small portable and inexpensive NMR lab on a chip devices Current Members Daniel Kennedy Clancy Slack Matt Ramirez Phuong Dao Jinny Sun Muller Gomez Collaborators David Wemmer UC Berkeley Chemistry Matthew Francis UC Berkeley Chemistry References 1 A J Moule M M Spence S I Han J A Seeley K L Pierce S Saxena A Pines Amplification of Xenon NMR and MRI by Remote Detection Proceedings of the National Academy of Sciences 100

    Original URL path: https://pines.berkeley.edu/research/remote-detection (2015-04-17)
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  • Laser-Polarized Xenon Based Molecular Sensors | Pines Lab
    protein scaffolds have dramatically increased the amount of sensors that can be associated with a single molecular interaction and the development of contrast agents that take advantage of relaxation properties for improved signal 9 12 Sensitivity is further enhanced by combining the hyperpolarization step with chemical exchange saturation transfer hyperCEST which exploits the exchange of dissolved 129 Xe nuclei between bulk solution Xe water and cryptophane molecular cages Xe cryptophane 13 14 The cage environment produces a chemical shift 130 ppm upfield from that of Xe water A narrow bandwidth radiofrequency pulse is applied at the chemical shift of Xe cryptophane saturating those spins without affecting the bulk pool of dissolved Xe If the pulse duration is long relative to the mean residence time of Xe inside cryptophane 10 3 10 2 s saturation accumulates in the Xe water pool due to the exchange of spins resulting in a decrease in signal intensity that can easily be detected or imaged 15 17 Current Work Currently the group is working on coupling the Xe molecular sensor to microfluidic devices and optimizing the relaxation properties These projects hope to improve sensitivity and eventually be coupled to projects in Ultra Low Field NMR and Laser Enhanced NMR Current Members Matt Ramirez Daniel Kennedy Clancy Slack Phuong Dao Keunhong Jeong Muller Gomes Jinny Sun Collaborators Dave Wemmer UC Berkeley Chemistry Matt Francis UC Berkeley Chemistry References 1 H Lee T Yoon and R Weissleder Ultrasensitive detection of bacteria using core shell nanoparticles and a NMR filter system Angew Chem Int Ed 48 2009 5657 5660 2 T G Walker and W Happer Spin exchange optical pumping of noble gas nuclei Reviews of Modern Physics 69 1997 629 3 I C Ruset S Ketel and F W Hersman Optical Pumping System Design for Large Production of Hyperpolarized Xe129 Phys Rev Lett 96 2006 053002 4 K W Miller N V Reo A J M Schoot Uiterkamp D P Stengle T R Stengle and K L Williamson Xenon NMR Chemical Shifts of a General Anesthetic in Common Solvents Proteins and Membranes PNAS 78 1981 4946 4949 5 Persaud K Dodd G Analysis of Discrimination Mechanisms in the Mammalian Olfactory System Using a Model Nose Nature 299 352 355 1982 6 Lamagna A Reich S Rodriguez D Boselli A Cicerone D The use of an electronic nose to characterize emissions from a highly polluted river Sensors and Actuators B Chemical 131 121 124 2008 7 Giordani D S Siqueira A F Silva M L C P Oliveira P C de Castro H F Identification of the biodiesel source using an electronic nose Energy Fuels 22 2743 2747 2008 8 Ahn S M Simpson R J Body fluid proteomics Prospects for biomarker discovery Proteomics Clinical Applications 1 1004 1015 2007 9 C Hilty T J Lowery D E Wemmer and A Pines Spectrally Resolved Magnetic Resonance Imaging of a Xenon Biosensor Angew Chem Int Ed 45 2006 70 73 10 M M Spence E J Ruiz S M

    Original URL path: https://pines.berkeley.edu/research/mol-imag-sens (2015-04-17)
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  • Ultra Low-Field to Zero-Field NMR | Pines Lab
    observing the precession of proton spins in a large sample of water 13 In the 1980 s the Pines Lab began exploring zero field NMR to measure solid samples via field cycling techniques 14 21 Despite needing to acquire point by point early zero field NMR was successfully used to measure structure dynamics and configuration in solid powders nematic and smectic liquid crystals 22 24 and isotropic liquids 20 Research also lead to the development of zero field NMR at high field 25 which allowed for the recovery of information about local interactions which are usually overwhelmed by the interaction with the magnetic field With the introduction of non inductive magnetic field detectors first Superconducting QUantum Interference Devices SQUIDs 26 27 and now atomic magnetometers the direct detection of NMR signals at zero field has become feasible 1 4 By shortening the experimental timescales associated with indirect detection and dramatically increasing spectral resolution a new era of zero field NMR research has emerged building on previous successes to extend our understanding and explore new applications Current Directions Our current efforts involve the development of optically detected zero field NMR spectroscopy for applications in chemical analysis 10 28 geology and fundamental physics 29 This includes the development of theoretical understanding of zero field spectra 10 30 31 the implementation of hyperpolarization schemes 11 12 and the expansion of the information available at zero to ultra low field by the inclusion of symmetry breaking fields and alignment media 9 People Involved John Blanchard Tobias Sjolander Jonathan King Collaborators Dmitry Budker UC Berkeley Physics John Kitching NIST References 1 Budker D Romalis M Optical Magnetometry Nature Physics 3 227 234 2007 2 Seltzer S Ph D Thesis 3 I M Savukov S J Seltzer and M V Romalis Detection of NMR signals with a radio frequency atomic magnetometer Journal of Magnetic Resonance 185 214 2007 4 Ledbetter M P Crawford C W Pines A Wemmer D E Knappe S Kitching J Budker D Optical detection of NMR J Spectra at Zero Magnetic Field Journal of Magnetic Resonance 199 25 29 2009 5 Karplus M Contact Electron Spin Coupling of Nuclear Magnetic Moments Journal of Chemical Physics 30 1 11 15 1959 and Karplus M Vincinal Proton Coupling in Nuclear Magnetic Resonance Journal of the American Chemical Society 85 18 2870 2871 1963 6 Sutter K Autschbach J Journal of the American Chemical Society 134 13374 13385 2012 7 Pietrzak M Benedict C Gehring H Daltrozzo E Limbach H H J Mol Struct 2007 844 845 222 231 8 Grzesiek S Cordier F Jaravine V Barfield M Prog Nucl Mag Res Sp 2004 45 275 300 9 Ledbetter M P Theis T Blanchard J W Ring H Ganssle P Appelt S Blu mich B Pines A Budker D Near Zero Field Nuclear Magnetic Resonance Physical Review Letters 107 107601 2011 10 Theis T Blanchard JW Butler MC Ledbetter M P Budker D Pines A Chemical analysis using J coupling multiplets in zero field NMR

    Original URL path: https://pines.berkeley.edu/research/ultra-low-field-zero-field-nmr (2015-04-17)
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  • Hyperpolarization | Pines Lab
    and therefore the atom may be selected 1 It was then demonstrated that polarization can be transferred to noble gas atoms such as Xenon 129 and Helium 3 during spin exchange collisions of gaseous atoms 2 Our group currently applies hyperpolarized Xenon 129 for targeted cellular imaging as well as remotely detected imaging for chemical analysis Another example is the nitrogen vacancy NV center which is an electronic defect in diamond with total spin equal to 1 Upon optical excitation the triplet spin state preferentially relaxes through intersystem crossing to the ground state resulting in polarization to the 0 spin state with 80 efficiency This means that by simply pumping the NV center with green light the system can be nearly completely polarized to the spin 0 state Lastly the symmetry of singlet states such as parahydrogen can be exploited to produce complete polarization in newly formed bonds incorporating these systems which can then be probed and manipulated for a number of purposes 3 4 History Because magnetic resonance techniques universally and fundamentally rely on adequate polarization members of the field have worked towards the development of hyperpolarization methods for decades Early work was focused on the development of a body of techniques referred to as dynamic nuclear polarization which is now implemented in commercial systems for application to solids and solutions surfaces materials as well as micro and macromolecular biological systems 5 11 The Pines group has purposed these techniques of hyperpolarization DNP optically pumped systems and parahydrogen for a number of applications A few examples include photochemical DNP for time resolved magnetic resonance imaging the use of alkali vapor magnetometry and PHIP for chemical analysis at zero field and the NV defect for sensitive magnetometry Current Work We are currently exploring three different mechanisms for hyperpolarization This includes polarization transfer from the nitrogen vacancy defect in diamond to other nuclear spins in the lattice the development of a microfabricated Xenon polarizer capable of both hyperpolarizing Xenon and detecting encoded Xenon with increased sensitivity and testing the breadth of the SABRE Signal Amplification by Reversible Exchange method with parahydrogen and different catalysts Current Members Haijing Wang Chang Shin Anna Parker Claudia Avalos Daniel Kennedy John Blanchard Tobias Sjolander Collaborators Dmitry Budker UC Berkeley Physics Jeffrey Reimer UC Berkeley Chemical Engineering John Kitching NIST References 1 Kastler A Optical Methods of Atomic Orientation and of Magnetic Resonance Journal of the Optical Society of America 47 6 460 465 1957 Happer W Optical Pumping Reviews of Modern Physics 144 2 170 250 1972 2 Goodson B M Nuclear Magnetic Resonance of Laser Polarized Noble Gas Nuclei in Molecules Materials and Organisms Journal of Magnetic Resonance 155 157 216 2002 R G Walker W Happer Spin exchange optical pumping of noble gas nuclei Reviews of Modern Physics 69 2 629 642 1997 3 A Abragam The Principles of Nuclear Magnetism Clarendon Oxford England 1961 C P Slichter Principles of Magnetic Resonance Springer Verlag Berlin 1989 4 Rossini A J Zagdoun A Lelli

    Original URL path: https://pines.berkeley.edu/research/hyperpolarization (2015-04-17)
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  • Solid-State NMR | Pines Lab
    inherently more complicated than its liquid state counterpart This arises from the appearance of anisotropic interactions such as dipole dipole coupling and nuclear quadrupolar that would be averaged to zero in an isotropic liquid These interactions have several effects One is the broadening of the NMR spectrum obscuring chemical shift information Methods to overcome this broadening are the foundation of solid state NMR However these complex interactions also provide the opportunity to gain greater information from the NMR spectrum For example probing the dipole dipole couplings between nuclear spins can show the spatial arrangement of atoms and quadrupolar splittings are a probe of the local electric field gradients Relaxation timescales and lineshapes can also inform about dynamics in systems such as porous media History The unique challenges of solid state NMR have required a series of innovations over the last 40 50 years These include magic angle spinning in order to remove the complicated dipole dipole interaction and dynamic nuclear polarization to increase sensitivity Some contributions from the Pines lab include cross polarization from protons to dilute spins to achieve enhanced sensitivity 1 multiple quantum spectroscopy to increase resolution 2 and double rotation spinning to remove the nuclear quadrupolar interaction 3 Modern solid state NMR is now employed across a wide range of fields including solid state physics in semiconductors materials science and engineering and study of large biomolecules Current Work Current work in our lab involves the application of solid state NMR techniques and theories to a myloid fibrils structural biology o riented samples s olid state polarization and detection and NV spin dynamics Current Members Aleks Kijac Jonathan King Claudia Avalos Haijing Wang Chang Shin Anna Parker John Blanchard Tobias Sjolander Collaborators David Wemmer UC Berkeley Chemistry Stanley Prusiner UCSF IND Dmitry Budker UC Berkeley Physics References 1

    Original URL path: https://pines.berkeley.edu/research/SSNMR (2015-04-17)
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  • About the Pines Lab | Pines Lab
    to probe the structure dynamics and function of materials in the solid state Current research interests involve novel approaches to spin polarization detection molecular sensing and miniaturization Examples include the technology of hyperpolarized xenon molecular sensing by which magnetic resonance spectra and images can be labeled with chemical structural and functional information the combination of optical spectroscopy and magnetic resonance to provide new experiments that retain the optimal properties of

    Original URL path: https://pines.berkeley.edu/about (2015-04-17)
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