Fluorescein III CEP
Notes: Installs a 6-carboxyfluorescein internally or at the 5'-terminus of an oligonucleotide using a DMT-bearing phosphoramidite with a 1,3-diol framework. Description: For the installation of fluorescein at the 5'-terminus of an oligonucleotide, the phosphoramidite "6-FAM" (5'-Fluorescein CEP, BA 0054), which does not bear a DMT group, is a popular choice. However, the lack of a trityl group precludes multiple additions or assaying the coupling step. Fluorescein II CEP ("6-FAM II", BA 0253), which features the same tether length as 6-FAM, but includes a DMT group.1 We now offer Fluorescein III CEP ("6-FAM III",BA 0334) which also includes the DMT group, but with a 1,3-diol framework. This extended framework serves two functions. First, the one carbon extension disfavors cyclic phosphate formation when the DMT group is removed, thereby minimizing label loss. Second, the 1,3-diol framework maintains the natural 3-carbon atom internucleotide phosphate distance, which diminishes duplex destabilization.2 The DMT may also be used to facilitate cartridge purification with on-column detritylation, e.g. with Fluoro-Pak columns. Download Product Information here.
1. 5'-Fluorescein II CEP incorporates 6-carboxyfluorescein. The 5-carboxyfluorescein isomer of this product (CA Reg. No. 144676-14-2) is also known. See: Theisen, P.; McCollum, C.; Upadhya, K.; Jacobson, K.; Vu, H.; Andrus, A. Tetrahedron Lett. 1992, 33, 5033-5036.2. Nelson, P.S.; Kent, M.; Muthini, S. Nucleic Acids Res. 1992, 20 , 6253-6259.
|
 |
