Antisense LNA GapmeR Control (15) - 5' Fam

The QIAGEN Antisense LNA GapmeR Control (15) - 5' Fam is a 15-nucleotide negative-control oligonucleotide supplied as a single-stranded antisense probe with a 6-carboxyfluorescein (FAM) reporter dye conjugated at the 5' end. It is built on the same locked nucleic acid (LNA)/DNA gapmer architecture used in the QIAGEN Antisense GapmeR design pipeline, with LNA-modified flanks surrounding a central DNA gap that supports RNase H recruitment, but the sequence is scrambled so that it does not match any annotated human, mouse, or rat transcript in standard reference databases. This makes it the standard negative control for knockdown experiments in which the only variable being measured is the chemistry and delivery of the gapmer rather than target engagement.

Because the 5' FAM fluorophore emits in the green channel (excitation approximately 494 nm, emission approximately 521 nm), the control is routinely used to benchmark transfection efficiency and intracellular uptake by fluorescence microscopy, flow cytometry, or a microplate reader before committing to a gene-specific GapmeR. Researchers commonly co-transfect it with a target-specific LNA GapmeR to confirm that observed phenotypic changes reflect on-target antisense activity rather than off-target toxicity, oligonucleotide chemistry effects, or transfection reagent artifacts. Because RNase H-recruiting gapmers must reach the nucleus or cytoplasm to function, the FAM signal is also a convenient proxy for subcellular biodistribution in cell culture.

Each control is supplied dried in a single vial and should be reconstituted in nuclease-free water or TE buffer to a working stock, commonly 50 uM. For long-term storage, the dried oligo is stable at -20 °C protected from light; once resuspended, single-use aliquots are recommended to limit freeze-thaw cycles. Working concentrations in the low nanomolar range, for example 25-100 nM final, are typical for transfection of mammalian cells using lipid-based reagents such as Lipofectamine or RNAiMAX. The reagent is sold for research use only and is intended for in vitro antisense oligonucleotide studies.