title: Two-dimensional NMR spectroscopy of (13)C methanol at less than 5 μT.
abstract: Two-dimensional (2D) spectroscopy is one of the most significant applications of nuclear magnetic resonance (NMR). Here, we demonstrate that the 2D NMR can be performed even at a low magnetic field of less than 5μT, which is ten times less than the Earth's magnetic field. The pulses used in the experiment were composed of circularly polarized fields for coherent as well as wideband excitations. Since the excitation band covers the entire spectral range, the simplest two-pulse sequence delivered the full 2D spectrum. At 5μT, methanol with (13)C enriched up to 99% belongs to a strongly coupled regime, and thus its 2D spectrum exhibits complicated spectral correlations, which can be exploited as a fingerprint in chemical analysis. In addition, we show that, with compressive sensing, the acquisition of the 2D spectrum can be accelerated to take only 45% of the overall duration.
authors: (a)Center for Biosignals, Korea Research Institute of Standards and Science, Daejeon 350-340, Republic of Korea. Electronic address: jhshim@kriss.re.kr.
authors: Jeong Hyun
authors: JH
authors: Shim
authors: (a)Center for Biosignals, Korea Research Institute of Standards and Science, Daejeon 350-340, Republic of Korea.
authors: Seong-Joo
authors: SJ
authors: Lee
authors: (a)Center for Biosignals, Korea Research Institute of Standards and Science, Daejeon 350-340, Republic of Korea.
authors: Seong-min
authors: SM
authors: Hwang
authors: (a)Center for Biosignals, Korea Research Institute of Standards and Science, Daejeon 350-340, Republic of Korea.
authors: Kwon-Kyu
authors: KK
authors: Yu
authors: (a)Center for Biosignals, Korea Research Institute of Standards and Science, Daejeon 350-340, Republic of Korea; (b)Department of Medical Physics, University of Science and Technology, Daejeon 305-333, Republic of Korea.
authors: Kiwoong
authors: K
authors: Kim
keywords: COSY; SQUID detection; Two-dimensional NMR; Ultra-field NMR