Krotz Achim H, Cole Douglas L, Ravikumar Vasulinga T
Isis Pharmaceuticals, Inc., Carlsbad, California 92008, USA.
Nucleosides Nucleotides Nucleic Acids. 2003 Feb;22(2):129-34. doi: 10.1081/NCN-120019499.
The removal of 4,4'-dimethoxytrityl (DMTr) groups from oligonucleotides at low pH and the acid lability of the glycosidic linkage of purine nucleotides constitute an inherent conflict in preparative oligonucleotide chemistry. The use of a mildly acidic NaOAc buffer (10 mM, pH 3.0-3.2) allows adjustment of the pH in a range where the progress of the DMTr removal reaction can be monitored conveniently by HPLC and the optimum reaction time can be calculated. As a result, oligonucleotides with minimum depurination are obtained.
在低pH条件下去除寡核苷酸上的4,4'-二甲氧基三苯甲基（DMTr）基团以及嘌呤核苷酸糖苷键的酸不稳定性，构成了制备寡核苷酸化学中一个固有的矛盾。使用轻度酸性的醋酸钠缓冲液（10 mM，pH 3.0 - 3.2）可以将pH调节到一个范围内，在此范围内，DMTr去除反应的进程可以通过高效液相色谱（HPLC）方便地监测，并且可以计算出最佳反应时间。结果，得到了脱嘌呤最少的寡核苷酸。
