Physical & Dilution Data
Dilution volumes (in ml) are for 0.1M solutions in dry acetonitrile (4050). Adjust accordingly for other concentrations. For µmol pack sizes, products should be diluted as 100µmol/ml to achieve 0.1M, regardless of molecular weight.
The use of 0.1M oxidiser must be avoided to prevent oxidation of the biotin. However, should this occur, there is no adverse affect on the biotin-avidin coupling.
Coupling, Deprotection & Purification
Biotin-CE Phosphoramidite (2140) – A 15min coupling time is recommended. This is stable to most deprotection conditions.
Biotin-TEG-CE Phosphoramidite (2132) – A 12-15min coupling time is recommended. Most deprotection conditions are applicable. For optimal yield, oligos are prepared DMT ON, with removal of the DMTr group after cleavage and deprotection. Otherwise, the 1,2-diol configuration allows cleavage of the biotin TEG during deprotection.
3’-Biotin-TEG CPG (2353) – Since non-nucleosidic solid supports have a slower detritylation rate than nucleosidic supports, it is recommended than an additional detritylation be carried out. Note in this case an initial capping step must be avoided. Most cleavage and deprotection conditions are applicable.
Biotin-dT-CE Phosphoramidite (2067) – An extended coupling time of 15min is recommended. Most cleavage and deprotection are applicable. The t-butylbenzoyl group, used to aid the solubility and to protect the biotin, is removed during deprotection.
5’-Biotin-CE Phosphoramidite (2109) – A 5min coupling time is recommended. The trityl group is slow to detritylate, therefore removal on the synthesiser requires an additional deblocking step. If the biotin DMTr group is retained to aid cartridge purification, we recommend that the oligo is left in contact with the TFA solution for 10min.
Storage & Stability
All compounds are stored in a freezer at –10 to –30°C. 2140 & 2132 are stable in solution for 2-3 days, 2109 for 1-2 days, and 2067 for 3-5 days.