Article page image


“Best Oligo ordering system I've ever used, and I've been ordering oligos since 1992!”

-       Andrew B. PhD

In the genomics era, where the unlimited possibilities of discovering new genetic frontiers are limited only by your budget and time, we have made enhancements to our oligo portfolio to allow you to reach a little further faster and within your budget and time. Don't sacrifice speed or quality in your pursuit of groundbreaking science.

Express Oligos at no extra charge

Finally, a service that is in step with the pace of your research and within your budget. Order Express Oligos at the price of regular oligos as late as 5:00 pm EST and have them delivered next day with Overnight Shipping. Don't let high per-base price of synthesis or other handling charges make a dent in your tight budget and slow down your work.
To learn more about this service, click here.

The Pioneer of high-throughput oligo synthesis

As a pioneer in the art of high-throughput, automated custom oligo synthesis, Eurofins Genomics continues to develop innovative ways to serve its customers. Our scientists routinely use these oligos to perform DNA sequencing (using the Sanger method or Next Generation Sequencing technologies), cloning, gene synthesis, and qPCR services for our clients successfully.

When you order a custom DNA oligo from us, you get:

  • Easy online ordering interface
  • Single stranded custom DNA*
  • Synthesis scales from 0.01 μmole to 10 μmole
  • Huge variety of available modifications
  • Different purification options to choose from
  • Delivered dry or hydrated (normalized)
  • Shipped in tubes or 96-well plates

High Quality Oligos. Fast Turn-Around Times
With a view to ensure that your research is not delayed due to the delivery of reagents that function as expected, our custom DNA oligos are:

  • Synthesized using highly efficient phosphoramidite chemistry
  • Synthesized in a high-throughput production facility
  • Processed using highly automated technologies
  • Assayed by MALDI-TOF MS analyses and OD measurement
  • Monitored by a sophisticated barcode driven system

*To order linear, double-stranded DNA oligos, please visit the GeneStrands gene fragments page here.

Additional Services

Besides having the oligos purified by our purification specialists, we offer additional services based on the type of oligo(s) ordered or the intended application.

NGS Grade processing service

Multiplex next generation sequencing projects will yield more accurate demultiplexing results when the salt-free or HPSF-purified oligos processed using the NGS grade protocol offered by Eurofins Genomics are used during library preparation. To learn more about the NGS Grade processing service offered for salt-free custom oligos, click here.

cGMP oligos

Our DNA Synthesis lab at Louisville is equipped to synthesized oligos with customized requirements, lot-to-lot reproduceability and full-process traceability. To learn more about the benefits of oligos manufactured using cGMP, please visit the cGMP Oligonucleotides page.


Wide range of synthesis scales, purification options and turnaround time

We perform MALDI-TOF MS analysis on every custom DNA Oligo; infact we pioneered 100% MS testing in 1998. You can place an order for one or several oligos. For orders with large number of oligos, we recommend that you have the oligos delivered in plates.

Features Oligos in Tubes Oligos in Plates
Synthesis Scales (in nmoles) 10, 25, 50, 250, 1000, & 10,000 4, 10, 25, 50, & 2250
Modifications Several Fewer
Degenerate bases (see below) Single letter IUB code and predefined compositions
Available Oligo Lengths (in nt) 5–125
Synthesis Chemistry β-cyanoethyl Phosphoramidite coupling
Default Purification Salt-free purification
Other Purification Options  HPLC, PAGE, 2-Step HPLC, PAGE
Delivery Formats Dry or in solution (normalized) Dry or in solution (normalized)


Typical Turnaround Times for Standard Custom Oligos in Tubes

*The following values depend on the size and specifications of the order.

Synthesis Scale (nmol) Purification Delivered in (days)
10 nmol (Length: 5–60 nt)
25 nmol (Length: 5–80 nt)
Salt-Free 1
50 nmol (Length: 5–90 nt) Salt-Free 1
250 nmol (Length: 5–125 nt)
1,000 nmol (length: 5–125 nt)
Salt-Free 2
10,000 nmol (Length: 5–100 nt) Salt-Free 3

Typical Turnaround Times for standard Custom Oligos in Plates

Synthesis Scale (available lengths) Purification Delivered in (days)

4 nmol (Length: 5–60 nt)

Salt-Free 3

10 nmol (Length: 5–60 nt)
25 nmol (Length: 5–80 nt)

Salt-Free 3
50 nmol (Length: 5–90 nt) Salt-Free 3
PAGE Inquire
250 nmol (Length: 5–125 nt) Salt-Free 3
PAGE Inquire 
1,000 nmol (Length: 5–125 nt)
Salt-Free Inquire
PAGE Inquire


Standard IUPAC/IUB single letter codes for degenerate bases
Degenerate bases in primers serve a useful purpose in amplifying homologous genes from other species; more so when the amino acid sequence of the homologous protein from the species is known. The presence of degeneracy in the bases of the primer sequence accommodates the potential difference in the genetic sequence and yields an amplified product. To order oligos with such degenerate bases in the sequence, include the single letter code for the base as recognized by IUPAC and IUB to incorporate equal quantities of each base represented by that letter at the desired positions. Please note that these degenerate bases are not available for the oligos synthesized at the 4 nmol synthesis scale.

Single Letter Code Represents
B C, G, T (not A)
D A, G, T (Not C)
H A, C, T (Not G)
K T, G (Keto)
M A, C (Amino)
N A, C, G, T (Any base)
Single Letter Code Represents
R A, G (Purine)
S G, C (Strong)
W A, T (Weak)
V A, C, G (Not T)
Y C, T (Pyrimidine)

Custom DNA oligos at Eurofins Genomics are synthesized by coupling the relevant series of β-cyanoethyl phorphoramidites on pre-packed controlled-pore solid supports before being deprotected, de-salted, quantitated and being subject to quality control assessment. Typical coupling efficiencies achieved using our automated synthesis platforms are greater than 99%. The coupling efficiencies, when coupled with the length of the oligo sequence to be synthesized, essentially determine the yield of the oligo. Eurofins Genomics has optimized its synthesis scale and sequence length using its traditional high-throughput synthesis platforms to produce high-quality oligos of different lengths.

Lengths of oligonucleotides available in tubes and plates at different synthesis scales

Synthesis Scale (nmol) Available Lengths (in nts)
10 5–60
25 5–80
50 5–90
250 5–125
1,000 5–125
10,000 5–100


Purification options available for oligos in tubes and plates based on the length of the oligo and the synthesis scale:

Purification Option Purity Level Range of Oligo Length (in nts) Synthesis Scales (in nmoles)
Salt-Free na 5–125 10, 25, 50, 250, 1000, 10000
HPLC >85% 5–100 50, 250
HPLC 2-Step >90% 5–125 250, 1000, 10000
PAGE ˜90% 20–125 50, 250
PAGE 2-Step >90% 20–125 250, 1000


Please note that some oligos, particularly those containing modifications, are offered only with specific purification options. To see the yield of standard unmodified oligos based on the purification and length of the oligo, please visit the yields and purifications page.  

At Eurofins Genomics, we recognize that your research is valuable. To ensure that the oligos synthesized at our facilities meet all the requirements of your experimental application we have streamline the production process and implemented several quality controls at different stages of the production process. The quality control checks implemented at various points during the production process are displayed below:

Custom -dna -quality

Production process

The integration of the e-commerce site with the back-end laboratory information management systems (LIMS) ensures that each synthesized oligo is tracked through the various steps in the production process. As soon as an oligo order is placed on the ecom site, the automated order confirmation email is sent and the details of the order is transferred to the production lab without any loss in the order data. A unique barcode assigned to each oligo order ensures that the production status of an oligo can be monitored at any given instance.

Quality Control Processes

Quality controls processes are designed to evaluate both individual oligos or the total process.

Quality Control for Oligos

Every oligo is assayed using mass spectra. Shorter oligos (≤50 nts long) are typically evaluated using Matrix-Assisted Laser Desorption Ionization (MALDI) Time-of-Flight (TOF) mass spectrometry, while the longer oligos (≥50 nts) are analyzed by Electro-Spray Ionization (ESI) mass spectrometry. For oligos used in special applications, e.g., qPCR probes, purification and analysis is carried out using HPLC.

Quality Control for Production Processes

To assess the whole production process flow, orders for production control primers and probes are placed randomly each day. These orders proceed through the work-flow anonymously and are evaluated in qPCR reactions or assessed by our Quality Assurance team.