Studies that shed light on the mechanism of recognition and photophysical signal transduction are crucial for an efficient design of high throughput screening and selection approaches. For example, conformational changes of DNA have been linked to fluorescence changes of dopamine nanosensors while redox processes have been ruled out. Recently, it was also shown with combined Thz and fluorescence spectroscopy that local hydration changes are the key for engineering optimal sensor responses. Such insights refine the design considerations of the high throughput-based approaches discussed in this perspective. However, one should not see them as competing approaches but rather complementary that benefit from each other and can inform efficient decisions for the experimental design.