Microfabricated magnetic bead polydimethylsiloxane microarrays

Bead-based technologies are an attractive alternative to classical microarrays due to the high surface area of the beads which enables the immobilization of large numbers of probe molecules leading to increased kinetics and improved signal/noise ratios. A simple, versatile and inexpensive method for the fabrication of magnetic bead arrays is presented. The beads are first assembled into silicon pyramidal wells that have been fabricated by established microfabrication techniques and then mounted onto the apex of PDMS pyramids that replicate the silicon substrates by replica moulding. The bead arrays were used to detect oligonucleotide target sequences for the pathogenic avian H5N1 flu virus and results indicated that superior signal/noise ratios could be achieved compared to those from a classical microarray format.