Choosing the right DNA oligos for your application

Oligonucleotides are the starting point for many of today’s biology research, drug discovery and diagnostics applications. These highly technical applications demand high-quality oligonucleotides for success. Custom DNA oligos at Life Technologies are synthesized on a highly automated, computer-controlled system using standard cyano-ethyl phosphoramidite chemistry. Coupling efficiencies are monitored throughout synthesis of each oligonucleotide by trityl analysis, ensuring the quality of the process, not just the end product. Post-synthesis QC, mass spectrometry for short oligos and capillary electrophoresis (CE) for long oligos, ensure quality.

Choosing the synthesis scale and purification option that is best for your application depends on the nature of your downstream applications. The table below is designed to help you choose the right oligos and purification methods for your application.

In general, Cartridge purification is fast and economical but may compromise purify or yield depending on the oligo sequence (sequences with 5’ G’s can be problematic). HPLC is more time consuming but gives excellent purity up to 55 bases. Above 55 bases, it becomes increasingly difficult to differentiate full-length product from n-1 failure sequences. PAGE gives excellent resolution even with very long oligos but generally sacrifices yield for quality.








  • 25 nmole – 10 µmole
  • 5 – 100 bp
  • Removes salts but not failure
  • 50 nmole – 1 µmole
  • 7 – 55 bp
  • Removes failure sequences
  • Provides 80% full-length sequence
  • 50 nmole – 10 µmole
  • 10 – 55 bp
  • Removes failure sequences
  • Provides >85% full-length sequence
  • 50 nmole – 10 µmole
  • 7 – 100 bp
  • Removes failure sequences
  • Provides > 90% full-length sequence

Standard PCR



Specialty PCR




cDNA Library Construction





Fluorescent Sequencing




Next-Generation Sequencing







Gel Shift Assays