Custom Oligo Nucleotides
MIDLAND is primarily engaged in Custom RNA synthesis, Custom RNA synthesis along with DNA polymers and RNA polymers. MIDLAND’S experience in custom oligonucleotide synthesis is unsurpassed in the biotechnology industry. For over 30 years, MIDLAND’s products have been used by researchers worldwide and are backed by years of custom synthesis experience. MIDLAND´s products are sold for research purposes only and are not to be used for diagnostic or drug purposes nor are they to be administered to humans or to animals intended for human consumption.
The focus of the MIDLAND business plan is to be able to make a single oligonucleotide when a unique molecule is needed and then to be able to make hundreds or thousands of similar oligos or gram quantities of the same sequence as the successful project passes from a research idea to full-scale production.
Custom DNA Synthesis
MIDLAND´S synthetic DNA and RNA oligonucleotides are manufactured using state-of-the-art synthesizers that have the capability of producing 1, 12 or 96 oligonucleotides at a time. We have the present capacity to produce several thousand custom oligonucleotides per day. Because MIDLAND’s manufacturing process integrates:
- Lengths up to 180 bases
- Several synthesis scales – 0.02, 0.05, 0.2, 1, 5, 10, and larger
[up to 100 micromole]
- Several purification options
- More than 400 modifications
MIDLAND can truly produce a “custom oligonucleotide”. Every MIDLAND oligonucleotide is accompanied by a Certificate of Analysis that includes:
- Description of synthesis chemistry
- Purification method
- Yield information
- Molecular weight
Custom RNA Synthesis
MIDLAND offers RNA synthesis as a standard service. RNA synthesis is considerably more complicated and demanding than the analogous DNA synthesis, principally due to the presence of an additional hydroxyl group on the sugar. Not only must this hydroxyl group be stably protected during synthesis, it must be deprotected at the conclusion of the synthetic procedure. Monomers must be obtained from a source that provides pure 3′-phosphoramidites free of the 2′ regioisomer. Synthetic conditions must be employed that retain the 3′-5′ internucleotide linkage in order for the final product to be biologically active.
RNA preparation is further complicated by the inherently lower stability of RNA compared to DNA. The presence of ribonucleases in nature requires special RNAse-free precautions for containers and solutions. These factors, taken together, all contribute to the cost of RNA preparation, making it much more expensive to make than DNA. Our price includes purification and the yield should be expected to vary greatly, depending upon the length of the oligonucleotide. Please call or e-mail us for details.
Depending on your anticipated use, an alternative to RNA may be the use of 2′-O-Methyl RNA oligonucleotides in your research. 2′-O-Methyl RNA is resistant to most ribonucleases and, unlike RNA, is stable to hydrolysis by strongly alkaline solutions.
Phosphorothioate “S” Oligos
MIDLAND offers oligonucleotides containing phosphorothioate linkages, often referred to as “S” oligos. During the chemical synthesis of an “S” oligo, the oxygen atom that bears the negative charge in an ordinary phosphate-diester DNA is replaced with a sulfur atom to produce the phosphorothioate linkage. This replacement is particularly useful in anti-sense research as the phosphorothioate linkage is highly resistant to nuclease degradation. The best technique available for purifying “S” oligos is Reverse Phase (RP) HPLC. Many of the modifications that are available in DNA synthesis are also available with phosphorothioate linkages.