Nuclear magnetic resonance (NMR) spectroscopy is an analytical method that provides a wealth of chemical and structural information from complex biological samples. Unfortunately, NMR is an inherently insensitive technique which requires larger sample amounts than other chemical characterization methods. The overall goal of this proposal is to continue nanoliter-volume NMR probe development so that 5 - 1000 nanoliter volumes and picomole masses can be analyzed. The fundamental advance that enables such sensitivity' improvements is miniaturized radio- frequency coils for NMR signal detection. A major portion of this work involves the optimization of coil geometry and fabrication to maximize sensitivity and minimize spectral linewidth, to add a broad range of heteronuclear NMR capabilities, and to develop multiple microcoil probes. Probes with up to 16 microcoils will dramatically improve NMR throughput. The combination of NMR and separation methods provides unmatched structural elucidation capabilities. Specifically, optimized flow cells, acquisition parameters, separation modes and preconcentration methods will be developed for capillary electrophoresis and capillary liquid chromatography. A unique series of on-line NMR techniques will be developed to monitor the separation process including on-line temperature, flow rate and imaging techniques. The implementation of this technology greatly expands biological applications where mass limitations currently prevent NMR structural determinations. Specifically, diffusion-ordered NMR will be used to obtain quantitative information on the diffusion rates in specific populations of cellular organelles from a series of model cells from the marine mollusk Aplysia californica. Secondly, single cell NMR spectroscopy will be developed for identified neurons in Aplysia californica which will allow the major osmolytes and cytoplasmic and nuclear components to be measured in intact neurons, as well as the physico-chemical environment of these compartments. Thus, the nanoliter- volume NMR probes developed during this research will offer significantly improved mass sensitivity for a widening range of NMR analysis, enable NMR to be used with a variety of microseparation methods and allow a new range of biological applications.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Research Project (R01)
Project #
8R01EB002343-07
Application #
6636139
Study Section
Special Emphasis Panel (ZRG1-BMT (01))
Program Officer
Mclaughlin, Alan Charles
Project Start
1996-06-01
Project End
2005-04-30
Budget Start
2003-05-01
Budget End
2005-04-30
Support Year
7
Fiscal Year
2003
Total Cost
$224,122
Indirect Cost
Name
University of Illinois Urbana-Champaign
Department
Type
Organized Research Units
DUNS #
041544081
City
Champaign
State
IL
Country
United States
Zip Code
61820
Li, Yu; Webb, Andrew G; Saha, Saikat et al. (2006) Comparison of the performance of round and rectangular wire in small solenoids for high-field NMR. Magn Reson Chem 44:255-62
Zhang, Xiaofeng; Webb, Andrew G (2005) Magnetic resonance microimaging and numerical simulations of velocity fields inside enlarged flow cells used for coupled NMR microseparations. Anal Chem 77:1338-44
Webb, A G (2005) Microcoil nuclear magnetic resonance spectroscopy. J Pharm Biomed Anal 38:892-903
Webb, A G (2005) Nuclear magnetic resonance coupled microseparations. Magn Reson Chem 43:688-96
Zhang, Xiaozhong; Webb, Andrew (2004) Design of a capacitively decoupled transmit/receive NMR phased array for high field microscopy at 14.1T. J Magn Reson 170:149-55
Jayawickrama, Dimuthu A; Sweedler, Jonathan V (2004) Chiral separation of nanomole amounts of alprenolol with cITP/NMR. Anal Bioanal Chem 378:1528-35
Ciobanu, Luisa; Rubakhin, Stanislav S; Stuart, Jeffrey N et al. (2004) Characterization of the physicochemical parameters of dense core atrial gland and lucent red hemiduct vesicles in Aplysia californica. Anal Chem 76:2331-5
Jayawickrama, Dimuthu A; Sweedler, Jonathan V (2004) Dual microcoil NMR probe coupled to cyclic ce for continuous separation and analyte isolation. Anal Chem 76:4894-900
Jayawickrama, Dimuthu A; Wolters, Andrew M; Sweedler, Jonathan V (2004) Retention characteristics of protonated mobile phases injected into deuterated mobile phases in capillary liquid chromatography (LC) using on-line nuclear magnetic resonance (NMR) detection. Analyst 129:629-33
Li, Yu; Logan, Timothy M; Edison, Arthur S et al. (2003) Design of small volume HX and triple-resonance probes for improved limits of detection in protein NMR experiments. J Magn Reson 164:128-35

Showing the most recent 10 out of 11 publications