TRIMER - Oligonucleotide Production
a unique service for randomized oligos

The use of 2'-deoxynucleoside trimer phosphoramidites is a particularly efficient way to approach oligonucleotide-directed mutagenesis.
Of the 64 possible combinations of codons, only 20 codons are required to cover the 20 amino acids.
Unlike other methods of mutagenesis, libraries built of Trimer-oligonucleotides lead to no codon bias, no production of stop codons and custom mixes allow for control of codon abundance making them one of the most efficient tools to explore sequence space in protein regions that are important for function – even in nonsaturating conditions.
All available trimers which are listed in the link below have the protection scheme described by Kayushin et al (2-4).
The reaction factor of each new trimer-phosphoramidite lot will be determined by Ella Biotech before used in synthesis. The reaction factor is critical since the trimers will likely be mixed and they have differing reactivity in the coupling reaction.
With this method we can guarantee a correct distribution of the trimer-codons in the mix.

1. Zon, G., Gallo, K., Samson, C., Shao, K., Michael F. Summers, M., Byrd, R. Nucleic Acids Res, 1985, 13, 8181-8196.
2. Kayushin, A., Korosteleva, M., Miroshnikov. Nucleos. Nucleot. Nucleic Acids, 2000, 19, 1967-1976.
3. Kayushin, A., M. Korosteleva, . Miroshnikov, A. Nucleos Nucleot, 1999, 18, 1531-1533.
4. Kayushin, A., M. Korosteleva, . Miroshnikov, A. W. Kosch, W., Zubov, D., Piel N. Nucleic Acids Res., 1996, 24, 3748-3755.
5. Mauriala, T., Auriola, S., Azhayev, A., Kayushin, A., Korosteleva, M., Miroshnikov, A. J Pharm Biomed Anal, 2004. 34, 199-206.
6. Yagodkin, A., Azhayev, A., Roivainen, J., Antopolsky, M., Kayushin, A., Korosteleva, M., Miroshnikov, A., Randolph, J., Mackie, H. Nucleos. Nucleot. Nucleic Acids 2007, 26, 473-497.
7. Neylon, C. Nucleic Acids Res, 2004. 32, 1448-59.
8. Sondek, J. and D. Shortle, Proc Natl. Acad. Sci. U S A, 1992. 89,3581-3585.

Please contact us for further details or discuss your demands regarding these projects. You can also use our trimer -order form for your enquiry.

General information


  • library construction for protein mutagenesis using 2'-deoxynucleoside trimer phosphoramidites


  • no codon bias
  • no frame-shifts
  • high diversity of sequences against Standard NNK or NNS libraries
  • no stop codons

Quality and Service

  • We guarantee a variance in the allocation of each trimer in a 19-trimer mix of 2-9%. This is based on statistics of sequencing 300 clones!
  • We produce our degenerated oligos to 90-95% purity, based on 70mers with 4 to 8 couplings of trimer mixes. For purification we use HPLC and PAGE. The HPLC-method we use has been developed specifically for the purification of trimer-oligonucleotides which have given excellent results in successful trimer-projects.
  • All Trimer-codons will be quality checked by NGS before used in synthesis
  • Several modifications available for Trimer-Oligonucleotides (e.g. Biotin, Phos, Spacer etc.)
  • Special method used for library synthesis with length polymorphism
  • synthesis follows our quality standards according to ISO9001
  • further trimer-codons (custom codons) are available which are not listed in the overview - please enquire
  • high quality amplification primers will be provided free of charge
  • guaranteed yield: 3-5 nmol

Turnaround time
Depending on the size of the order we need at least 10 working days - please enquire

Overview Trimer Codons