Blinded unknown samples of DENV NS1 spiked into serum samples. The sample concentrations are shown though the assay and analysis were performed blind in random order. Thirty two samples including 9 blanks were prepared and randomly ordered. The samples were then split and evaluated in two separate plates using the MagPlex amplified assay with DD7-GS3K as the capture and Bt-DD5-GS3K as the tracer sdAb. Shown are the results for each NS1 positive sample tested in duplicate sorted by concentration and type. All 9 blanks (not shown) were determined to be negative, with ratios ranging 0.925 to 1.44, while all the unknown samples containing NS1 were identified as positive with ratios of 2.0 or greater. All results in the order tested are shown in Supplementary Fig. 9.