Design Guidelines

Purification and delivery options

Our standard practice is to deprotect and desalt all oligonucleotides to remove small molecule impurities, quantify the oligo by UV spectrophotometry to provide an accurate measure of yield, and perform quality control (QC) by mass spectrometry.

Additional purification is recommended for many modified oligonucleotides including heavily LNA-substituted, unmodified oligonucleotides. For demanding applications, such as single nucleotide discrimination and antisense inhibition, purification may improve the performance of the oligonucleotide. For these situations, we typically recommend a standard RP-HPLC purification, which routinely results in >85% purity.

For long oligonucleotides (>60 bases) and for applications requiring oligonucleotides with a very high purity, we recommend PAGE, IE-HPLC (ion-exchange HPLC) or dual HPLC. RNase-free HPLC purification can be applied for oligonucleotides that will be used in applications sensitive to ribonucleases. Please contact us for further information regarding our purification offerings.

Na+ salt exchange is available for oligonucleotides that will be used in applications in which the presence of minute amounts of toxic salts can cause unwanted side reactions.

Modifications and secondary structure of the oligonucleotide might affect yield and purity guarantees. Please contact us to obtain information on guaranteed yield and purity.

By default, oligonucleotides are delivered lyophilized in standard tubes.

  • Orders of 24 oligonucleotides or more can be delivered in 96-well plates.
  • Orders of 96 oligonucleotides or more can be delivered in 384-well plates.

We also offer options for delivery in plates, such as normalization to the same concentration across the plate, delivery of the full yield or mixing of normalized oligonucleotides in the same well.

Please contact us with any request for custom delivery of your oligonucleotides.