What is the difference between oligo synthesis scale and final guaranteed yield?

There are two ways to place oligo orders with Bio-Synthesis.
  1. You may order by oligo starting synthesis scale.
  2. Or you may order by final guaranteed yield ( net amount shipped to our customer ).
Oligo synthesis scale is the starting amount of the respective column used to produce the oligo, whereas final guaranteed yield is the actual amount of oligo we ship to you in terms of nanomole (nm) OD (Optical Density) or actual physical weight of the oligomer

Most oligonucleotides are ordered by starting molarity of the inital material (particularity with scales of less than 15 umole) with no guarantee of final yield. The coupling efficiency of synthesis depends upon the sequence composition, length, purity requested and other factors. At Bio-Synthesis we are able to optimize the coupling efficiency since a small drop in coupling efficiency may cause a large reduction in yield. This can be demonstrated by calculating the theoretical yield using the formula:


where X represents the average coupling efficiency and y represents the number of couplings.

For example, at 20 mer (which requires 19 couplings), the theoretical yield is 82% assuming ideal conditions. However, the actual yield for sequences of average dificulty would be around 60-65%. As oligos grow longer than 20 mer, the yield will drop sharply. Some oligos require further modification after synthesis, which will lessens the final yield even further. Therefore, depending on the importance of the actual amount needed to conduct your experiment, we suggest that you place your order by indicating the net amount needed which is knows as the Final Guaranteed Yield.