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RNA Longmers

metabion is now raising its standards even higher with our longly tried and trusted RNA Longmers which are offered at highest quality up to a length of 140 nts.

Our offer in a nutshell:

✓ metabion RNA Longmers are offered at a pearless standard length of 140 nts;

HPLC-purified by default*;

✓ Delivered with complementary mass-spec trace documentation;

✓ Unmatched standard selection of modifications for RNA 81-140 nt Longmers;

✓ Our standard RNA modifications for RNA 60-80 nt Longmers;

✓ Available in dry, single tube format.

As we like to say:

It matters what you actually get for your money!

If you intend to use RNA longmers for CRISPR-Cas applications, you might consider using Breaking-Cas (Spanish National Centre for Biotechnology, CNB-CSIC) to design the guideRNA portion of your RNA longmer.

Our standard custom RNA longmers portfolio

  • 4 final yields based on length-independent delivered quantities from 1–10 nmol for single-stranded oligos from 60–140 nucleotides:
    •   1 nmol
    •   2 nmol
    •   5 nmol
    • 10 nmol
  • 100% HPLC purification*;
  • Quality Control by Mass-Check for best quality:

Authentic mass-spec trace of a RNA 100 longmer.

  • an extended standard selection of single modifications (5´, internal, 3´) for RNA longmers ranging from 81–140 bases;
  • for RNA oligos up to 80mers you can draw from our rather “unlimited” resources available for our standard RNA modification portfolio;
  • delivery in single tubes under dry shipping conditions;
  • comprehensive and best value pricing scheme.

* Please note that HPLC purification assures that the hightest possible percentage of our delivered RNA Longmers will be a full-length product. Many oligo providers claim that their coupling efficiency reaches 99.3%.

This is currently a standard coupling efficiency and presents no guarantee in terms of delivered full-length product. With their standard 99.3% coupling efficiency, the crude synthesis-extract of oligonucleotides as long as 120-140 nucleotides will contain a quantity of full-length product not exceeding 25% of the ordered amount. Our known commitment and ability to deliver defined amounts of final product becomes evident when we deliver HPLC purified, 100% Mass-Checked RNA Longmers.

Fluorescent Modifications

Non-Fluorescent Modifications

Any question? Visit our FAQs page or contact us!

FAQ – you ask, we answer


There are two ways of ordering:

  1. The preferred way is order transmission through our Web Order Portal for most convenient online shopping (please refer here for further details).
  2. You can order by sending us an e-mail at with our pre-formatted excel order file as attachment. Download respective Order Form.

When you write your e-mail, please make sure to include the following required information in the excel template:

  1. Name of the RNA Longmer.
  2. Sequence of the RNA Longmer in 5’-3’ orientation.
  3. Yield range.
  4. Purification required.
  5. Modifications.

If you are a new customer, please additionally provide us with:

  1. Your shipping and billing address.
  2. Any other information like Purchase Order number, VAT number (VAT only for customers resident in the EU), etc.

In case you choose to transmit orders via e-mail using your own format(s), we need to alert you that above mentioned information in bold print is obligatory for processing your order. Due to extra efforts necessary for individual order format transfer into our system, order processing will take longer as compared to preferred web orders and pre-formatted e-mails. Please note that only files updated to the latest excel/word version (e.g. .xlsx or .docx) are accepted.

How can you convert files to newer formats?
Open the file in a recent Office program and save the file in a newer format. For this go to “File” → “Save as” and choose the newer format from the “Save as type” dropdown menu.

If you want to connect your eProcurement System with our Web Order Portal (e.g. OCI - Open Catalog Interface), please simply contact our Customer Service (


RNA longmers are usually processed within 8–15 business days including purification and quality control, depending on sequence length/complexity and modification level.

Freight forwarders delivery time to the final destination is not included. In terms of "counting" working days, orders placed past 15:00 (Munich time) are considered to be next day's order. Be assured that we try to process your order as quickly as possible without compromising on quality!


The current maximum length of standard RNA Longmers is 140 bases. For RNA Longmers longer than 140 bases, please inquire.


For details please click here.


Yes, we do! Please, visit our dedicated page.

To learn more about CRISPR-Cas, click here.


Yes, we do! This is part of our standard RNA portfolio! Delivery/shipping condition of dsRNA like for all our RNA oligos is “dry”. Simply dissolve the pellet in annealing buffer and apply a suitable annealing protocol. For your convenience we recommend to follow our guidelines on our download section.


For RNA oligonucleotides between 5–40 nts and for a quantity delivered between 10–100 nmol, we offer RNA oligonucleotides desalted as well as HPLC purified. Over 100 nmol and 40 nts our default purificatiom method is HPLC! Such RNA require HPLC purification to guarantee the top quality required for your experiments. For such RNA Longmers, HPLC purification is included in our price per base/probe/duplex. Visit our Portfolio.


Our default delivery form is dry. This ensures maximum stability during transport and storage.


The label on the oligo tube shows basic information like oligo name, name of person who ordered, oligo sequence including modifications, oligo ID, amount of RNA (OD260 and nmol), Tm, and molecular weight.

In addition, you will receive a synthesis report containing more detailed information on the physical-chemical properties of the oligo, such as base composition, base count, purification grade, amount of RNA (OD260 and nmol), Tm and molecular weight.
Each and every oligo produced and delivered is analyzed by either MALDI- or ESI-ToF before release, and Mass-Check documentation/spectra will be provided upon additional charges (desalted RNA) or free of charge (HPLC purified RNA). The following terminology is used for differentiating between offered QC:

Mass Check
Standard quality control performed on each and every oligo. Either MALDI- or ESI-ToF, subject to the "nature of the oligo", and metabion internal procedures. This service is free of charge and will always be delivered with hard copies of the Mass Check spectrum for all our HPLC purified RNA products.

Analytical HPLC
Mass Check (MALDI-ToF or ESI-ToF subject to the "nature of the oligo" and metabion internal procedures) and explicitly ordered Analytical HPLC (please read FAQ "What is the difference between preparative and analytical HPLC?"). Product delivered with analytical HPLC and MS spectra. Additional charges apply.


RNA duplexes are significantly more resistant to nucleases than a single strand RNA oligonucleotide. However, maintaining sterile, RNAse free conditions is always recommended as a precaution. Dried pellets are stable at room temperature for 2–4 weeks, but should be placed at –20 °C or –80 °C for long term storage. Under these conditions, dry RNA is stable for at least one year.