Lecture

Dynamic Nuclear Polarization: Fundamentals

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Description

This lecture introduces the concept of Dynamic Nuclear Polarization (DNP) in magnetic resonance, focusing on enhancing signal-to-noise ratio in liquid-state NMR. Topics include the basic steps of DNP, the use of polarizing agents like [1-13C] Sodium Pyruvate, and the impact of natural abundance on sensitivity. The lecture also covers the theoretical framework behind DNP, the role of electron polarization, and the requirements for achieving optimal polarization. Additionally, it discusses the contributions of key figures like Albert W. Overhauser and the potential applications of DNP in improving NMR sensitivity.

Official source

Related concepts (15)

Nuclear magnetic resonance

Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are perturbed by a weak oscillating magnetic field (in the near field) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. This process occurs near resonance, when the oscillation frequency matches the intrinsic frequency of the nuclei, which depends on the strength of the static magnetic field, the chemical environment, and the magnetic properties of the isotope involved; in practical applications with static magnetic fields up to ca.

Nuclear magnetic resonance spectroscopy

Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique to observe local magnetic fields around atomic nuclei. This spectroscopy is based on the measurement of absorption of electromagnetic radiations in the radio frequency region from roughly 4 to 900 MHz. Absorption of radio waves in the presence of magnetic field is accompanied by a special type of nuclear transition, and for this reason, such type of spectroscopy is known as Nuclear Magnetic Resonance Spectroscopy.

Signal-to-noise ratio

Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than noise. SNR is an important parameter that affects the performance and quality of systems that process or transmit signals, such as communication systems, audio systems, radar systems, imaging systems, and data acquisition systems.

Nuclear Overhauser effect

The nuclear Overhauser effect (NOE) is the transfer of nuclear spin polarization from one population of spin-active nuclei (e.g. 1H, 13C, 15N etc.) to another via cross-relaxation. A phenomenological definition of the NOE in nuclear magnetic resonance spectroscopy (NMR) is the change in the integrated intensity (positive or negative) of one NMR resonance that occurs when another is saturated by irradiation with an RF field. The change in resonance intensity of a nucleus is a consequence of the nucleus being close in space to those directly affected by the RF perturbation.

Carrier-to-noise ratio

In telecommunications, the carrier-to-noise ratio, often written CNR or C/N, is the signal-to-noise ratio (SNR) of a modulated signal. The term is used to distinguish the CNR of the radio frequency passband signal from the SNR of an analog base band message signal after demodulation. For example, with FM radio, the strength of the 100 MHz carrier with modulations would be considered for CNR, whereas the audio frequency analogue message signal would be for SNR; in each case, compared to the apparent noise.

Related lectures (64)

Spin Relaxation in Magnetic Resonance

Introduces the fundamentals of spin relaxation in magnetic resonance, covering spin-lattice and spin-spin relaxation, and rotational motion in liquids.

Nuclear Magnetic Resonance: Principles and Applications

Explores the principles and applications of Nuclear Magnetic Resonance, covering chemical structure elucidation, peak interpretation, and medical imaging.

NMR Experiments: Basics and Applications

Explores the basic steps in magnetic resonance, including INEPT pulse sequences and two-dimensional NMR experiments like COSY and NOESY.

Quantum Optics I: Stern-Gerlach Experiment

Explores the Stern-Gerlach experiment, strong measurements, cavity quantum electrodynamics, and quantum optomechanics.

Nuclear Overhauser Effect