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Updated: Jun 13, 2026

Magnetic Levitation Coupled with Portable Imaging and Analysis for Disease Diagnostics
Published on: February 19, 2017
Magnetic levitation in the analysis of foods and water
Katherine A Mirica1, Scott T Phillips, Charles R Mace
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Abstract:
This paper describes a method and a sensor that use magnetic levitation (MagLev) to characterize samples of food and water on the basis of measurements of density. The sensor comprises two permanent NdFeB magnets positioned on top of each other in a configuration with like poles facing and a container filled with a solution of paramagnetic ions. Measurements of density are obtained by suspending a diamagnetic object in the container filled with the paramagnetic fluid, placing the container between the magnets, and measuring the vertical position of the suspended object. MagLev was used to estimate the salinity of water, to compare a variety of vegetable oils on the basis of the ratio of polyunsaturated fat to monounsaturated fat, to compare the contents of fat in milk, cheese, and peanut butter, and to determine the density of grains.
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