The Alexa Fluor 488 Oligonucleotide Amine Labeling Kit provides a simple method for labeling amine-modified oligonucleotides with our bright, photostable, green-fluorescent Alexa Fluor 488 dye (which is spectrally similar to fluorescein). Oligonucleotides labeled with this kit can be used as primers and as probes in hybridization experiments but should not be used for automated DNA sequencing since the Alexa Fluor dye in the kit is supplied as mixed isomers. The kits have been optimized for labeling reactions with 50 µg of a 5'-amine—modified oligonucleotide, 18 to 24 bases in length.