Construction and Application of a Static Magnetic Field Exposure Apparatus for Biological Research in Aqueous Model Systems and Cell Culture.

With the growth of the quantum biology field, the study of magnetic field (MF) effects on biological processes and their potential therapeutic applications has attracted much attention. However, most biologists lack the experience needed to construct an MF exposure apparatus on their own, no consensus standard exists for exposure methods, and protocols for model organisms are sorely lacking. We aim to provide those interested in entering the field with the ability to investigate static MF effects in their own research. This protocol covers how to design, build, calibrate, and operate a static MF exposure chamber (MagShield apparatus), with instructions on how to modify parameters to other specific needs. The MagShield apparatus is constructed of mu-metal (which blocks external MFs), allowing for the generation of experimentally controlled MFs via 3-axial Helmholtz coils. Precise manipulation of static field strengths across a physiologically relevant range is possible: nT hypomagnetic fields, μT to < 1 mT weak MFs, and moderate MFs of several mT. An integrated mu-metal partition enables different control and experimental field strengths to run simultaneously. We demonstrate (with example results) how to use the MagShield apparatus with , planarians, and fibroblast/fibrosarcoma cell lines, discussing the modifications needed for cell culture systems; however, the apparatus is easily adaptable to zebrafish, , and 3D organoids. The operational methodology provided ensures uniform and reproducible results, affording the means for rigorous examination of static MF effects. Thus, this protocol is a valuable resource for investigators seeking to explore the intricate interplay between MFs and living organisms. Key features • A comprehensive roadmap, suitable for undergraduate to advanced researchers, to construct an apparatus for in vitro and in vivo experiments within uniform static magnetic fields. • Designed to fit inside standard incubators to accommodate specific environmental conditions, such as with cell culture, in addition to stand-alone operation at room temperature. • Requires two DC power supplies and 3D printer access for the Helmholtz coils, Plexiglass and mu-metal foil for the partition, and a milli/Gaussmeter for calibration. • Requires ordering a custom mu-metal shell from a commercial resource (using provided schematics), where lead times for delivery can vary from 2 to 4 months.