Investigation of metal-binding properties of clinically significant compounds using magnetic bead-based agglutination assay

We present a novel strategy for investigating metal-binding properties of metformin and propanediimidamide (PDI) using magnetic-bead-based agglutination assay in a fully-integrated and automated setup. Metformin, the first-line treatment drug for type-2 diabetes is understood to interact with mitochondrial copper, which is hypothesized to be related to its anti-hyperglycaemic properties. PDI, although being a structurally closely-related compound does not exhibit anti-hyperglycaemia like metformin. Using our automated setup involving low sample volume and low sample-to-answer time, the results demonstrate that metformin but not PDI disrupts copper-bridged magnetic-bead clusters, consistent with the poss ibility that interaction with copper is significant in metformin's anti-hyperglycaemic action.