Antisense oligonucleotides 5 -capping

Hoke GD, Draper K, Freier SM, et al. Effect of phosphorothioate capping on antisense oligonucleotide stability, hybridization and antiviral efficacy versus herpes simplex virus infection, Nucleic Acid Res 1991 20 5743-5748. 

Figure 6 illustrates some separations of a 20-mer antisense oligonucleotide with a neutral backbone. With the sample diluted in water, a symmetrical peak is obtained for a small 100-mbs injection (data not shown). The buffer is 100 mM CAPS, pH 11.7, with 6 M urea. The solute is separated as an anion, with thymine and guanine being ionized at the high pH. Figure 6 shows the separations at expanded scale. Some subtle but surprising observations are made. In 1 M salt diluent, two impurity peaks on the tail of the main component show improved resolution, while the impurity peak that elutes just before the main... 

To extend this work so that [Eu(13)] + could be attached to an antisense oligonucleotide, which would target the capped end of a mRNA, it was necessary to convert the nitro group of ligand 22 to an... 

Dheur, S. et al., Polyethylenitnine but not cationic lipid improves antisense activity of 3 -capped phosphodiester oligonucleotides. Antisense Nucleic Acid Drug Dev., 9,515,1999. 

---