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siRNA for Gene Silencing

 
 
siRNA, or small interfering ribonucleic acid, is a type of RNA that is involved in a number of biological processes, most notably RNA interference. RNA interference is a regulatory process that is used to control and limit the expression of specific genes. Regulatory active siRNA consists of annealed, complementary RNA sequences, usually 21-25 nucleotide in length and with symmetric 2 nucleotide 3’ overhangs.
Chemical synthesis enables the incorporation of DNA nucleotides as overhangs thereby rendering the siRNA-duplex more stable against nuclease degradation.
 

Features and Benefits

 
 
High Quality
  • all siRNAs are MALDI-TOF MS controlled before shipment
  • Renowned siRNA supplier for top research institutes, pharma/biotech companies
 
Convenient
  • Ready to use: siRNA is manufactured as ready to use aqueous solution (40 µM siRNA duplex, 10 mM NaCl, 10 mM TrisHCl, pH 7.5)
  • Useful additional services:
    • Modified siRNAs on request (e.g. GalNAc)
    • Guaranteed knock down: if you use our free siRNA design service and let us produce ≥ 3 siRNAs, we guarantee that at least one of the synthesized siRNAs will reduce mRNA levels by at least 70%  

 

 
 
Cost Effective
  • Very competitive pricing for volume as well as repetitive orders
  • High guaranteed yields; average delivery yield usually significantly higher
  • Free siRNA design service available
 
Excellent Technical Support
  • Trained scientists with molecular biology background are happy to support you (from 8 am to 5 pm)
User-friendly Online Ordering System
  • New and easy-to-use online portal, a user-friendly input mask and other helpful tools (e.g. order tracking and history, convenient search and re-order option)
 
 
Do you need a guaranteed knock-down or do you need help with the design of the siRNAs?
We do offer a free design service at following conditions:
 
We guarantee that at least one of the synthesized siRNAs will reduce mRNA levels by at least 70% when ≥3 siRNAs are designed and used.
 
Service is limited to 5 genes per customer and day.
 
If you do not achieve the guaranteed 70% knock down, we design/synthesize additional 3 siRNAs for you. However, you need to show us that your experiment was performed according to the following parameters:
  • Delivery efficiency of siRNA: >90%
  • Effective concentration applied: 100 nM
  • Incubation: at least 48 hours
  • Positive control: included

 

Remark: If you want to design customized siRNA yourself we recommend using siDirect software design tool.

 

Overview

 

siRNA, or small interfering ribonucleic acid, is a type of RNA that is involved in a number of biological processes, most notably RNA interference. RNA interference is a regulatory process that is used to control and limit the expression of specific genes. While most RNA is single stranded, siRNA is made up of two complementary strands of RNA nucleotides similar to those in DNA. Usually siRNA molecules are 21-25 nucleotide double-stranded RNA (dsRNA) duplexes with symmetric 2 nucleotide 3’ overhangs.

 

Figure 3. The RNA interference process and the biochemical machinery involved. Double-stranded RNA is cut into short pieces (siRNA) by the endonuclease Dicer. The antisense strand is loaded into the RISC complex and links the complex to the mRNA strand by base-pairing. The RISC complex cuts the mRNA strand, and the mRNA is subsequently degraded.

siRNA Duplexes

 

Microsynth supplies siRNA duplexes from standard (2x21-mers) to extended length (2x27-mers) at different levels of purity and scales, depending on the intended application:

  • Desalted siRNA (for screening purposes)
  • HPLC and PAGE purified siRNA (for screening and for use in cells)  
  • In vivo animal studies (on request)

 

Product Characteristics:

Synthesis scale1
Desalted
HPLC
PAGE
OD2602
[nmol]2
OD2602
[nmol]2
[OD260] 2
[nmol]2
0.04 µmol
9
21
4
8
not available
0.2 µmol
16
35
7
16
2
5
Higher Scales
on request
          
Genomics
on request
 7        
Classical siRNA duplexes (2x21-mers) have unit prices; if you need longer duplexes, each additional RNA base will be priced accordingly. Modified siRNAs are available upon request.
 
1 The synthesis scale represents the initial amount of 3' bases (starting material).
2 Yields indicated represent guaranteed yields and apply to a 2x21mer; Calculation: 1 OD = ~2.5 nmol (please note that this calculation is based on sequences with virtually homogenous distribution of the 4 RNA bases)
 

Control siRNAs

 
Microsynth supplies the following two types of control siRNAs:
 
  • Pre-synthesized siRNAs
  • Customized or scrambled siRNAs
 
 
Pre-synthesized siRNAs
 
Product Characteristics:
siRNAs Other specifications
Lamin A/C - CUGGACUUCCAGAAGAACAdTdT
  • desalted
  • delivered as 4 nmol aliquots
  • sequences are published and are not known to show any off target effects
GFP - GCAGCACGACUUCUUCAAGdTdT
Luciferase  - CGUACGCGGAAUACUUCGAdTdT
Neg. control - AGGUAGUGUAAUCGCCUUGdTdT
 
Ordering Information:
You need only control siRNA:
  • Write an email containing your account information (Name, delivery address, login, password) to administration@microsynth.ch. Indicate the name and number of the control siRNA(s) you would like to order.

 

Customized or scrambled siRNAs
 
Product Characteristics:
You will find useful information in the section siRNA Duplexes.
 
Ordering Information:
  • Write an e-mail to info@microsynth.ch and provide us with the accession number or alternatively with the mRNA sequence of your target gene. We perform scrambling of your siRNA sequence and do a BLAST to theoretically exclude any interference with known mRNA sequences. Then we provide you with the siRNA sequence.

How to Order

 

  • Enter our webshop
  • Click on siRNA in the blue “DNA/RNA Synthesis” domain
  • Select Normal Entry in order to type or copy/paste the desired sequence information etc. or alternatively select Upload Entry by using our convenient Excel template (can be downloaded during ordering )