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WELCOME TO THE PHARMACY WORLD
Nuclear Magnetic Resonance (NMR) Spectrometer
The nuclei of certain isotopes behave as though they are bar magnets. Two of the more relevant nuclei are hydrogen-1 and carbon-13. When compounds containing these isotopes are placed in a strong external magnetic field, the nuclear magnets orient parallel to the external field. Irradiating them with electromagnetic energy in the radio part of the spectrum causes them to flip in the opposite direction. When they return to the lower energy orientation, the added energy is emitted as a photon. The energy of the photon is characteristic of the enviroment of the nucleus being observed.
An instrument known as a Nuclear Magnetic Resonance (NMR) Spectrometer, is designed to allow the observation of the nuclei as they relax from resonance. The NMR spectrometer excites the nuclei and then observes the signal as the energy of the nuclei decays back to the ground state.
Our instrument uses a 60 MHz radio
frequency generator. It is designed to pulse the sample and then record the
signal given off by the relaxing nuclei. The data obtained is then
mathematically treated by an operation known as a Fourier-Transform (FT). The
data can then be analyzed in order to give information about the molecule under
study. Non-identical nuclei exist in different chemical environments, and
therefore resonate at different frequencies. The peaks of an NMR spectra
indicate when a particular nuclei of the molecule was in resonance.
