5-FAM-X, SE

5-FAM-X, SE contains the aminohexanoyl spacer (known as 'X') between the FAM fluorophore and the succinimidyl ester. The 'X' spacer separates the fluorophore from the biomolecule to which it is conjugated. The 'X' spacer may potentially reduce the quenching that typically occurs when a fluorescein molecule is conjugated to proteins or other biopolymers (such as nucleic acids).