TQ2WS is designed to be a superior quencher to FAM, HEX, TET, JOE, TF2 and rhodamine 6G. TQ2WS has (a). much stronger absorption; (b). much higher quenching efficiency; and (c). versatile reactive forms with much greater water solubility than other existing quenchers for labeling oligonucleotides and peptides. This TQ2WS product is the most-water soluble and non-fluorescent quencher for labeling oligos and peptides. We have demonstrated that TQ2WS is extremely useful for enhancing the water solubility of hydrophobic peptides.