Faster downstream applications

Linear Fragments Synthesis

Doulix DNA synthesis provides linear, double-stranded DNA fragments up to 2.5 kbp and with industry leading fidelity. Designed for easier gene cloning, modification and applications including CRISPR/CAS editing, antibody development and more.

  • Fragment synthesis up to 2.5 kbp.
  • Industry leading fidelity – 1:30,000 oligo synthesis error rates.
  • Complexity as standard
  • From €0.12 per bp.

Key benefits

Reduce Mistakes

No more missing bp or frame-shifts as you copy and paste your sequences between your editor and your gene synthesis provider.

Intuitive UI

Our easy interface allows you to import different formats (.txt, .gb, and .fasta) and see, edit and annotate your sequence before synthesis.

Save time

No more wasting time waiting for pending orders to be confirmed. Check your sequence for manufacturability as you type.

Save Money

No more duplicate orders or last-minute surprises, get all-included quotes and re-use archieved fragments and constructs.

Our quality promise

DNA synthesis is conducted according to rigorous ISO 9001:2008 standards. Sequences are verified for accuracy via Gel Electrophoresis and for purity by UV absorption. We send nothing unless it passes QC; quality and function is our promise.
We’re so confident we won’t let you down, we’ll back it with a promise - The Doulix quality promise - if it’s not perfect, you don’t pay a thing.

The extra touch

Your dsDNA fragments arrive optimized for your application of choice. We’ve spent 2 years training neural networks to solve synthesis and assembly problems with real world experiments. Our tools now allow for greater first-time application success, on even complex sequences.

  • Comprehensive optimisation for cloning and manufacture.
  • Scarless assembly optimisation.
  • Codon optimisation and troubleshooting as standard.
  • Average two colonies for sequence perfect clone.


Our turnaround time may not be the fastest in the industry, but for good reason. Quality requires time and the additional error correction and rigorous quality controls we perform ensure it. Average turnaround on DNA synthesis is 11 days (and improving). But what counts is that with a greater than 90% as promised delivery success, it’s arriving when we say so. With synthesis you can rely on, you can be ready to go the moment your sample arrives.

  • Average 11-day turnaround time.
  • Lyophilized, linear dsDNA fragments.
  • Choose your purity grade from research level to endotoxin free.
  • E. coli stab agar and glycerol stock delivery options.
  • Add ons available for one stop shopping.
  • Customs and shipping handling included.

Accepted inputs: A, C, G, T, W (weak: A, T), S (strong: C, G ), M (amino: A, C), K (keto: G, T), R (purine: A, G ), Y (pyrimidine: C, T), B (not A), D (not C), H (not G), V (not T), N (any basebase)
Blast BP: 0
Sequence and name fields will be overridden
By selecting the biosafety level corresponding to the project, customer confirms that (i) such classification is correct and accurate and (ii) that the customer has read, understood and accepted the biosafety confirmation.
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