Tide Quencher™ 8WS (TQ8WS) is a non-fluorescent molecule designed to efficiently quench the fluorescence of IR fluorophores such as ICG, iFluor® 820, iFluor® 840 and iFluor® 860. It has the longest absorption wavelength among all the commercial quenchers. TQ8WS is designed to be the most effective IR quencher with (a). much stronger absorption, and (b). much higher quenching efficiency for IR dyes. Tide Quencher™ 8WS amine is primarily used for labeling biomolecules that contain a carbonyl group. It can be used in techniques such as polymerase chain reaction (PCR), real-time PCR, and DNA sequencing. In these applications, fluorescence signals are used to monitor the amplification or detection of specific DNA sequences. TQ8WS quenches the fluorescent signal until a specific event (like DNA strand separation or primer extension) occurs, leading to an increase in fluorescence that can be detected and quantified. Fluorescence resonance energy transfer (FRET)-based assays are widely used to detect and measure the presence of specific molecules in a sample. They involve the use of a fluorescent molecule (fluorophore) and a quencher molecule such as TQ8WS. The fluorophore emits light when excited by a specific wavelength of light, while the quencher molecule absorbs this emitted light, effectively "quenching" the fluorescence signal.