A smartphone-assisted paper-based colorimetric biosensor for rapid detection of dengue NS1 antigen.

Dengue virus infection poses significant health risks, so rapid and early diagnosis is essential to mitigate these risks effectively. In this study, a paper-based NS1 biosensor was developed using surface-modified gold nanoparticles (AuNPs) bioconjugated with the NS1 monoclonal antibody (mAb) for colorimetric detection. The paper-based NS1 biosensor exhibits a color change upon interaction with the dengue NS1 antigen. Color signals were captured using a smartphone, and the images were analyzed in ImageJ to extract red, green, and blue (RGB) intensities for quantitative analysis. The paper-based NS1 biosensor exhibited a linear response for the detection of dengue NS1 antigen over the concentration range of 75 to 250 ng/mL, with a linear regression coefficient (R2) of 0.997, a limit of detection (LOD) of 10.95 ng/mL, and a detection time of 15 minutes. The paper-based NS1 biosensor demonstrated good selectivity, precision (RSD < 5%), and recovery from 93.40% to 98.54% in human serum samples. These findings indicate that the paper-based NS1 biosensor has potential as a simple, low-cost, portable, and potential as point-of-care device for early detection of the dengue virus.