Abstract: The present invention describes microplates with arrays of wells containing magnetic inserts in the form of disks, cylinders or otherwise shaped materials with apertures in the centre for optical interrogation of the contacting solution. These inserts are capable of capturing ferro- and paramagnetic nano- and microparticles. The subject microplates find use in a variety of applications, including clinical and environmental assays, high throughput screening for genomics, proteomics and pharmaceutical applications, point-of-care in vitro diagnostics, molecular genetic analysis and nucleic acid diagnostics, cell separations, and bioresearch generally and high-throughput screening of materials for separation and catalysis.