| The Flying Cow |  |
Our Standard Grade means deprotected and desalted oligos unrestrictedly recommended for methods like PCR, (cycle) sequencing and hybridisation. |
| The Singing Flying Cow |  |
Our OPC (Oligonucleotide Purification CartridgeTM) purification is a kind of fast HPLC purification for unmodified oligos up to about 40 nucleotides in length. Non-DMT bearing failure sequences, by-products, and other impurities wash through the cartridge while the DMT group of the trityl-on oligos adsorb to the affinity column. After removal of the DMT group with mild acid the highly purified detritylated primer can be eluted. |
| The Super Cow |  |
Our HPLC purification by a computer controlled HPLC-system is the state-of-the-art method to precisely enrich for long full-length products. Its sensitive separation capability makes it possible to get purities up to 95%. Our special developed HPLC programs aren't "2-minute one cleans all kind of oligos programs" as you'll find it by many of our competitors. We have different programs for different types of oligos which have a run time up to 30 minutes. As a documentation of your oligos quality you'll get the HPLC chromatogram with your primers. |
From our experience in nucleotide synthesis chemistry you should avoid to design oligo-/ polynucleotides longer than 80 bases for high precise applications. Even if we can do up to 180-mers, the yield of full-length product will (coupling rates/cycle ~ 98.5-99.5%) dramatically decrease with the number of synthesis cycles and (de) protection, coupling and washing steps within each cycle can leave its track within the growing sequence (base modifications by oxidation, base insertions/deletions by formation of secondary structures, ...). Consequently, a precise sequence guarantee is very difficult to give and we have to double the price per base for oligos >80 nucleotides. NOTA BENE Price list DNA - unmodified oligos
To reduce any kind of side products to a minimum level we have developed a special HPLC protocol. Special columns and gradients as well as a very restricted cutting of the oligo peak make sure that the highest possible purity of oligos used for gene synthesis can be achieved. Consequently, there is a reduction of yield, but the final product will be of very high quality! Due to this special cleanup with lower yields no OD guarantee can be given. Please mention "Gene Synthesis Quality" in your order!
Quality Control
Quality control is the last step in the production process of custom oligonucleotides. Our Quality Management starts before the first step!
- Pre-synthesis control: Validation of incoming raw material/chemicals by running and checking test oligos makes sure that our reagents, which are exclusively purchased from audited and approved quality vendors, meet the requirements for providing best coupling efficiencies and consequently top quality primers.
- In-synthesis control: During synthesis, coupling rates are permanently checked by DMT monitoring - only high efficient (>98.5 %) cycles allow the continuation of the synthesis run!
- Post-synthesis control: Quantification (OD measurement) of the end product is a strong indicator for successful synthesis.
- End control: Analytical HPLC and Maldi-ToF spot checks are performed for final release of the product.
Our strict maintenance program for regular testing of the performance of our synthesizers is an additional "quality measure" taken from our side to guarantee our constantly high quality level.
For special requirements you can order Maldi-ToF documentation for your oligos at Euro 20.00/oligo.
For our high troughput oligos delivered in 96well plates a Maldi-ToF check of every single oligo is inclusive!
- Oligo synthesis separately from routine production by specially trained staff.
- Specially reserved instruments.
- Comprehensive and detailed documentation of individual production runs.
- Highly reliable purity of products provided by our special premium HPLC purification method and quality check by Maldi-ToF analysis (spectra will be part of the documentation!).