The assays can be provided as a custom multiplex with comparable performance to the individual assays. However, the custom multiplex will not be validated. There are no cross-reactivity issues between the two assays. The reason a multiplex was not created for these kits is because in human CSF, the Human Aß42 assay requires a 1:8 dilution to eliminate matrix effects, whereas the Human Total Tau assay requires only a 1:2 dilution. The multiplex will work well for tissue or cell supernatants where the dilution factors and matrix effects may not be significant. For custom multiplexes, the protocol may need to be optimized, but the validated Human Aß42 protocol may be used as a starting point for optimization.