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LNA primer and probe 주문

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주문취소를 원하시면 주문 후 30분 이내에 당사로 취소 의사를 전달해 주시기 바랍니다. 그 이후엔 취소가 불가능합니다.

Introduction

Locked Nucleic Acid는 2′-O, 4′-C methylene bridge를 포함하는 핵산 유사체의 한 유형입니다.


Figure 1. Structure of Locked Nucleic Acid and native-state DNA monomers.

Bridged nucleic acid (BNA)이나 inaccessible RNA 라고도 하는 LNA는 ribose 부분이 2′ 산소와 4′ 탄소를 연결하는 추가 다리로 변형된 RNA nucleotide입니다.
변형된 올리고뉴클레오티드의 결합 친화력을 증가시켜 생물학적 핵산에 비해 향상된 생체 안정성을 제공합니다.
이 변형체는 RNA, ssDNA 및 dsDNA에 대한 혼성화에서 보다 안정하다는 것이 입증되었습니다.

MGB in comparison to ZNA®-conjugated, LNA-modified oligonucleotides

MGB (Minor Groove Binder), ZNA®, LNA(Locked Nucleic Acids), and PNA (Peptide Nucleic Acid) are known to increase the Tm of an oligo sequence.
MGB (Minor Groove Binder) probes include a minor groove binder (MGB) moiety at the 3’ end that increases the melting temperature (Tm) of the probe and stabilizes the hybridization of the probe DNA to its target sequence.
The introduction of the minor groove binder moiety is sequence-independent, meaning the core sequence remains “unmodified”.

ZNA®s are oligonucleotides conjugated with repeated cationic spermine units that decrease electrostatic repulsions with target nucleic acid strands, and greatly improve hybridization properties by enhanced affinity to the complementary target sequence as well as increased stability of the formed duplex at an unprecedented specificity.
The “Tm boost” generated by adding ZNA® to either end of the oligonucleotide probe is significant and also sequence-independent.

In contrast, LNA probes rely on modified nucleotide chemistry with regard to the sugar component involved, while the organic base component is “unmodified” and thus follows Watson-Crick base-pairing rules when mixed with DNA or RNA bases in an oligonucleotide.
When incorporated into an oligonucleotide probe, locked nucleic acid monomers increase structural stability, resulting in a raise of the formed duplex melting temperature (Tm).
Locked Nucleic acids are not recognized by DNA/RNases as a substrate, hence LNA modified oligonucleotides also display significant resistance to nucleases.

In summary, Metabion offers all three duplex stability-enhancing modifications, and therefore provides the greatest flexibility in assay design and choosing the right option for your required application.

Featuring

• increased thermal stability and hybridization specificity
• increased Tm for short and AT-rich primers and probes (ΔTm/locked base approx. 2-6°C depending on sequence composition and “neighborhood” effects)
• Enhanced in-vitro and in-vivo stability due to increased endo- and exonuclease resistance
• Nontoxic, efficient, and effective building blocks for incorporation in antisense, mRNA, or other Nucleic Acid-based drug development candidates.

providing for

• efficient mismatch/SNP/allelic discrimination
• earlier Ct values
• higher signal level/signal-to-noise ratio
• facilitated and flexible designs for problematic target sequences – however, sequence-dependent.
• an excellent supplementation to our Tm/specificity/sensitivity increasing portfolio: ZNA and MGB modified oligonucleotides.

a wide range of Nucleic Acid-based applications like:

• PCR/real-time PCR/RT-PCR
• Microarrays/Capture probing
• Gene silencing
• In Situ Hybridization (ISH)

Delivery (발송)

Metabion normal olgo는 working days 기준 7~10일 정도 소요 되니다.
Modified oligo는 여기에 3-5일  이상 추가 시간이 소요 됩니다.

FAQ

Can I include PTO bonds in my LNA probe?
Yes, this is possible. Please mark the respective phosphorothioate bond by an axterix (*).
A fully thioated LNA 5´ATCGAT3´ Hexamer for example shall be depicted as follows:
5´ (+A) *(+T) *(+C) *(+G) *(+A) *(+T) 3´

What concentration of LNA probes are recommended for PCR applications?
A concentration of 0.2 µM of the LNA probe should be fine for most assays, but as usual, the optimal concentration should be determined experimentally. Due to the higher affinity of the probe to the target, the probe concentration might be lower.

What do I need to consider when designing an LNA probe?
When designing LNA-containing oligonucleotides, one should follow the basic rules of primer design, particularly paying attention to the location and number of LNAs.

For example, a typical 18-mer should contain a maximum of 7–8 LNAs.
Also, try to avoid stretches of more than 4 consecutive LNAs, which would result in very tight hybridization in that region.

Stretches of LNAs are to be avoided close to the 3′ end of an oligonucleotide. LNA will bind very tightly to other LNA residues.
Avoid self-complementarity and cross-hybridization to other LNA-containing oligonucleotides.

Finally, be sure to match the Tm of the primers, as usual, keeping in mind that each substitution of a standard nucleotide with an LNA increases the Tm by 2-6°C per LNA.

Oligo 보관시 유의점

일반적으로 올리고는 화학적으로 안정하며, -20℃에서 6개월 이상 안정하다고 볼 수 있습니다.
특히, 동결 건조한 상태에서는 매우 안정적이며 오래 보관하실 수 있습니다.
용액 상태에서도 안정하지만, nuclease등의 contamination에 의해 degradation 될 수도 있습니다.

또한, 올리고는 얼렸다 녹였다’를 반복하게 되면 분해를 촉진시켜 품질의 이상이 발생될 수 있습니다.
DNA의 경우는 acidic한 조건에서는 depurination에 의해 decompose될 수 있으니 pH를 낮추지 말아야 합니다.

LNA primer and probe 주문하는 방법

아래 링크의 올리고 주문양식을 다운로드하여 각 항목을 빠짐없이 작성후 oligo@bio-d.co.kr 로 보내주시면 됩니다.