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Purification Grades

General information on nucleic acid purification

Modern oligonucleotide synthesis via phosphoramidites is a complex multistep procedure. One elongation cycle consists of the following steps:

  • Deprotection of the 5'-hydroxy group
  • Coupling of the appropriate building block
  • Capping of unreacted 5'-hydroxy groups
  • Oxidation of the phosphittriester group to phosphatetriester

Even if all steps work optimally, a significant amount of incomplete sequences, called trityl-off failure sequences, will accumulate. The amount of these failure sequences depends on the chain length. The figure shows the amount of full length product depending on oligonucleotide length and three different coupling efficiencies (98.0 %, 98.5 %, 99.0 %).

As the oligonucleotide length increases, the amount of full length product decreases. Furthermore, in cases where chain length is greater than 50 bases, the growing chains interact with one another, causing the flow of chemicals through the column to slow down. Trityl-on failure sequences will be present, caused by inefficient detritylation, capping, oxidation or by depurination, resulting in post synthesis strand scissure during ammonia deprotection. In addition to trityl-off and trityl-on failure sequences, the base protecting groups in the form of their corresponding amides will be present within the crude reaction mixture. To fulfill the demand of purity for different applications, IBA offers a broad spectrum of standard and special purification methods.

DNA purification grades

Molecular biology grade purification

Salts, base protecting groups and short failure sequences up to 6 bases are removed efficiently. The amount of full length product depends on chain length and coupling yield. A typical 20mer with an average coupling yield of 98.5 % is composed of 70 % of full length product. This purification is recommended for oligonucleotides with a chain length up to 49 bases for standard molecular biology applications such as PCR, sequencing, etc..

Order Information

Product
Scale
Amounts [oD]*
 Price/oligonucleotide 
Molecular biology grade purification
0.01 µmol
0.5 -1.0
no charge
0.05 µmol
2.0 -4.0
no charge
0.20 µmol
10.0 -20.0
no charge
1.00 µmol
50.0 -100.0
no charge
15.00 µmol
600.0 -1200.0
no charge

* delivery amounts for a 20mer with an average base compostion of 5xA, 5xG, 5xC and 5xT

HPLC grade purification

Apart from salts and base protecting groups, the trityl-on HPLC step efficiently removes trityl-off failure sequences. The purity of the product depends on the nature and length of the sequence. IBA recommends this purification for all applications where full-length or high reproducibility are essential, including: cloning, PCR, mutagenesis, probes, modified oligonucleotides and oligonucleotides longer than 40 bases. This method is not able to remove trityl-on failure sequences.

Order Information

Product
Scale
Amount
Cat. no.
Price/oligonucleotide
HPLC grade purification
0.01 µmol
1-2 nmol
5-1020-001
11.00 EUR
0.05 µmol
5-8 nmol
5-1020-002
11.00 EUR
0.20 µmol
25-40 nmol
5-1020-003
12.00 EUR
1.00 µmol
100-150 nmol
5-1020-004
20.00 EUR
10.00 µmol   5-1020-006 147.00 EUR
15.00 µmol
1500-3000 nmol
5-1020-005
210.00 EUR
Double HPLC grade purification

This protocol consists of a trityl-on HPLC purification and a subsequently performed trityl-off HPLC purification. The second step completely removes oligonucleotides with base modifications and partly removes trityl-on failure sequences effectively.

Order Information

Product
Scale
Amount
Cat. no.
Price/oligonucleotide
Double HPLC grade purification
0.01 µmol
0.5-1 nmol
5-1030-001
21.00 EUR
0.05 µmol
2.5-5 nmol
5-1030-002
24.00 EUR
0.20 µmol
10.0-25 nmol
5-1030-003
29.00 EUR
1.00 µmol
50.0-100 nmol
5-1030-004
35.00 EUR
10.00 µmol   5-1030-006 252.00 EUR
15.00 µmol
750.0-1500 nmol
5-1030-005
341.00 EUR
Cell culture grade purification

This unique in-house development is a multi-step purification method for all oligonucleotides used in cell culture. It consists of two HPLC purification steps and one sterile filtration step.

Order Information

Product
Scale
Amount
Cat. no.
Price/oligonucleotide
Cell culture grade purification
0.05 µmol
1-3 nmol
5-1050-002
35.00 EUR
0.20 µmol
5 -15 nmol
5-1050-003
44.00 EUR
1.00 µmol
25 -50 nmol
5-1050-004
53.00 EUR
10.0 µmol   5-1050-006 420,00 EUR
15.0 µmol
500 -1000 nmol
5-1050-005
635.00 EUR
DS grade purification with double HPLC

This method was developed especially for ultra-short oligonucleotides with a chain length between 1 and 7 bases. It consists of an in-house developed 2 x HPLC purification and a desalting step.

Order Information

Product
Scale
Amount
Cat. no.
Price/oligonucleotide
DS grade purification
0.05 µmol
1 -3 nmol
5-1040-002
35.00 EUR
0.20 µmol
5 -15 nmol
5-1040-003
44.00 EUR
1.00 µmol
25-50 nmol
5-1040-004
53.00 EUR
10.00 µmol   5-1040-006 420.00 EUR
15.00 µmol
500 -1000 nmol
5-1040-005
635.00 EUR
Premium PAGE grade

Premium PAGETM is the most powerful method for complete removal of all types of failure sequences and intercalating dyes like TAMRA. Due to the lower recovery rate IBA cannot guarantee delivery amounts.

Recommended for the following products:

  • RNA
  • Oligonucleotides for biophysical application
  • FCS-Spectroscopy 

Order Information

Product
Scale
Cat. no.
Price/oligonucleotide
Premium PAGETM purification
0.05 µmol
5-1060-002
116.00 EUR
0.2 µmol
5-1060-003
142.00 EUR
1.0 µmol
5-1060-004
179.00 EUR
10.0 µmol 5-1060-005 1313.00 EUR
15.0 µmol 5-1060-006 1838.00 EUR
Reverse phase C18 HPLC purification

For oligonucleotides requiring more than standard reverse phase purification, such as double dye labeled oligonucleotides.

Order Information

Product
Scale
Cat. no.
Price/oligonucleotide
Reverse phase C18 HPLC purification
0,05 µmol
5-1022-002
32.00 EUR
0,2 µmol
5-1022-003
42.00 EUR
1 µmol
5-1022-004
47.00 EUR
10 µmol 5-1022-006 368.00 EUR
15 µmol 5-1022-007 525.00 EUR
Documentation

Order Information

Product
Cat. no.
Price/oligonucleotide
Premium PAGETM documentation
5-1070-000
12.00 EUR
HPLC documentation
5-1070-010
12.00 EUR

RNA purification grades

RNA HPLC grade purification

For certain applications RNA HPLC grade purification may be sufficient (but generally PAGE purification is recommended).

Order Information

Product
Scale
Cat. no.
Price/oligonucleotide
RNA HPLC grade purification

0.2 µmol
5-1021-003
47.00 EUR
1 µmol
5-1021-004
79.00 EUR
10 µmol 5-1021-005 578.00 EUR
15 µmol
5-1021-006
798.00 EUR
RNA double HPLC purification

Order Information

Product
Scale
Cat. no.
Price/oligonucleotide
RNA double HPLC purification
0.2 µmol
5-1024-003
69.00 EUR
1 µmol
5-1024-004
81.00 EUR
10 µmol 5-1024-005 609.00 EUR
15 µmol 5-1024-006 830.00 EUR
RNA cell culture grade purification

Order Information

Product
Scale
Cat. no.
Price/oligonucleotide
RNA cell culture grade purification
0.2 µmol
5-1023-003
58.00 EUR
1 µmol
5-1023-004
81.00 EUR
10 µmol 5-1023-005 609.00 EUR
15 µmol 5-1023-006 830.00 EUR
RNA desalting

Order Information

Product
Scale
Cat. no.
Price/oligonucleotide
RNA desalting
1 µmol
5-1041-004
23.00 EUR
10 µmol 5-1041-006 158.00 EUR
15 µmol
5-1041-005
189.00 EUR
Premium PAGE grade

Premium PAGETM is the most powerful method completely removing all types of failure sequences and intercalating dyes like TAMRA. Due to the lower recovery rate IBA cannot guarantee delivery amounts.

Recommended for following products:

  • RNA
  • Oligonucleotides for biophysical application
  • FCS-Spectroscopy 

Order Information 

Product
Scale
Cat. no.
Price/oligonucleotide
Premium PAGETM purification
0.05 µmol
5-1060-002
116.00 EUR
0.2 µmol
5-1060-003
142.00 EUR
1.0 µmol
5-1060-004
179.00 EUR
10.0 µmol 5-1060-005 1313.00 EUR
15.0 µmol 5-1060-006 1838.00 EUR
Documentation

Order Information

Product
Cat. no.
Price/oligonucleotide
Premium PAGETM documentation
5-1070-000
12.00 EUR
HPLC documentation
5-1070-010
12.00 EUR