Does LGC Biosearch Technologies recommend the use of FAST deprotecting or standard amidites?
LGC Biosearch Technologies recommends the use of FAST deprotection amidites such as: Adenosine-benzoyl,A(Bz;) Cytidine-acetyl,C(Ac); Guanosine-dimethylformamide, G(Dmf). For ultra-FAST deprotection, use the phenoxyacetyl (Pac) amidites: A (Pac), C (Pac) and G (Pac). Thymidine does not need a protecting group. The FAST deprotecting amidites are used when dye-labeled oligonucleotides are expected to be sensitive to basic conditions, especially when long time periods of incubation are involved. This is true for the CAL Fluor® dyes which are known to degrade in concentrated NH4OH.
The use of a tetrazole activator is in concurrence with our chemistry practices. LGC Biosearch uses ethylthioltetrazol (ETT) for all amidite productions. Be advised that the 4,5-dicyanoimidizole (DCi) activator, while less acidic, more soluble and more nucleophilic than tetrazol or ETT, does NOT work with our CAL Fluor chemistries.