Nuclear Magnetic Resonance (Nmr) Spectroscopy: Basic Principles and Phenomena, and Their Applications to Chemistry, Biology and Medicine

Abstract

Nuclear Magnetic Resonance (NMR) spectroscopy has made a tremendous impact in many areas of chemistry, biology and medicine. In this report a student-oriented approach is presented, which enhances the ability of students to comprehend the basic concepts of NMR spectroscopy and the NMR spectra of various nuclei. The origin of chemical shifts, coupling constants, spin relaxation and the Nuclear Overhauser Effect (NOE) will be discussed and their relation to molecular structure will be provided. A wide range of applications of NMR spectroscopy is presented, including exchange phenomena, the identification and structural studies of complex biomolecules, such as proteins, applications to food analysis, clinical studies, NMR as a microscope and magnetic tomography. [Chem. Educ. Res. Pract. Eur., 2002, 3, 229-252]

Data analysis of “krokodil” samples obtained by street-like synthesis

“…As “krokodil” is an aqueous solution, D 2 O was used as solvent for NMR analysis. The residual H 2 O signal (D 2 O was not 100% deuterated), a broad signal at 4.83 ppm, can overlap proton signals due to alcohols, phenols, amides or amines [7] . The absorptions in the range of 5–6 ppm are compatible with vinylic protons.…”

Nuclear Magnetic Resonance (NMR) Analysis of D - (+) - Glucose: A Guide to Spectrometric Structural Elucidation of Sugars

“…From figure 5, the diagonal and cross peaks formed by joining solid lines shows which protons are coupled to each other (mutual scalar coupling). OH 1 to OH 4 correlates with H 1 to H 4 respectively and OH 6 correlates with H 6 . Also, H 1 to H 5 correlates H 2 to H 6 respectively but H 5 correlates with two H 6 at 3.5604ppm and 3.4171ppm.…”

“…The Carbon that appears at 92.1375 ppm (table2) is C 1 because the most deshielded carbon will be the carbon that is attached to two oxygen atoms. The only inverted peak at 61.0899 ppm was CH 2 (even number of H) and so identified as C 6 . The remaining peaks were either for CH 3 or CH (odd number of H), but there was no CH 3 in the compound; hence the peaks might be for CH.…”

“…The principle of NMR spectroscopy is based on the magnetic properties of some nuclei [6]. Depending upon the atomic number and mass number of a nucleus, there is an associated angular momentum spin number.…”

“…For example, homonuclear correlated spectra are extremely useful for assigning 1H resonances while the complete assignment of 13 C-resonances is achieved by 1 H-13 C heteronuclear correlation [6,[12][13][14].…”