Ni-Co alloy coated QCM immunosensor to immobilize multiplex histidine-tagged proteins for label-free immunoassays

- QCM immunosensor to immobilize multiplex histidine-tagged proteins for immunoassays.
- Ni-Co film functioning as the metal-affinity immobilization layer.
- Attachment of proteins to Ni-Co surface is irrelevant to the species of proteins.
- Immunoassay with droplet containing His-tagged protein and various antibodies.