The principle and test procedure of dLFI. a The blood samples were enriched by the mAb 1F12-modified MNPs and then eluted for dLFI analysis. Schematic representation of the working principle of the dLFI for the detection of Aβ42Os (b), Aβ42Ms (c), Aβ42Ms and Aβ42Os (d), or without Aβ42Ms or/and Aβ42Os (e)