Magnetic micro-barcodes for molecular tagging applications

We present proof-of-principle experiments and simulations that demonstrate a new technology in which biological assay microscopic tags carrying multi-bit magnetic codes are used to label probe biomolecules. It is demonstrated that these 'micro-barcode tags' can be encoded, transported using micro-fluidics and are compatible with surface chemistry. We also present simulations and experimental results which suggest the feasibility of decoding the micro-barcode tags using magnetoresistive sensors. Together, these results demonstrate substantial progress towards meeting the critical requirements of a magnetically encoded, high-throughput and portable biological assay platform. We also show that an extension of our technology could potentially be used to label libraries consisting of ∼10⁴ distinct probe molecules, and could therefore have a strong impact on mainstream medical diagnostics.