AuNPs. The latter has potential to be leveraged to achieve higher sensitivity in bioassays using detection reagents conjugated with AuNPs. The high surface densities of AuNPs achieved with longer tethers is independently useful in affinity sensors that can take benefit of the resulting optical and spectroscopic properties, e.g. surface-enhanced spectroscopic detection of molecular analytes and colorimetric sensor for heavy metal detection. Overall, the findings in this report strongly support the need to factor in the tether length and flexibility into the design of interface functionalization to enhance the performance of affinity biosensors.