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TruGrade® DNA Oligos

Reduce barcode crosstalk in your multiplexed NGS experiments

Quality requirements for synthetic oligos used in next generation sequencing (NGS), such as indexed adapters and barcoded fusion primers, have reached unprecedented high levels. Traditional purification methods (e.g., HPLC) can effectively increase the amount of full-length oligo, but are incapable of reducing cross-contamination that can occur in co-synthesized oligos. In contrast to less sensitive applications where such oligo-to-oligo crosstalk can go unnoticed, the use of indexed adapters containing even low levels of cross-contamination can lead to barcode misalignment and sample misidentification, which may confound experiments requiring detection of rare variants.

TruGrade oligos are manufactured by proprietary methods that are proven to reduce index cross-talk and increase success of multiplex NGS experiments. With TruGrade oligos, you can:

  • Obtain DNA oligos with cross-contamination levels as low as 0.01%
  • Select from a variety of product options to suit your requirements
  • Experience the industry-leading quality and turnaround time for which IDT is known


DNA oligos


Ultramer® DNA oligos


DNA oligos


Ultramer DNA oligos


TruGrade DNA Oligos

With the rapid increased throughput of sequencing platforms, sample multiplexing has become a common method for making economical use of sequencing capacities. However, pooling indexed samples into one sequencing run comes with the risk of sample misidentification. While this can be attributed to many experimental factors, crosstalk during oligo synthesis is a major contributor. TruGrade DNA oligos are manufactured by an exclusive production process that reduces the risk of oligonucleotide crosstalk and, therefore, minimize the risk of barcode misalignment during multiplexing NGS applications.

The TruGrade synthesis and processing service is available on HPLC-purified DNA oligos and Ultramer® DNA oligos. They are available in plates and tubes, and can be formulated to your specifications. TruGrade DNA oligos can be used in a variety of applications including, but not limited to:

  • Library preparation to incorporate barcoded adapters for multiplexing next-generation sequencing
  • PCR using barcoded fusion primers for multiplex amplicon sequencing
  • Other molecular biology applications that are sensitive to oligo crosstalk


ParameterHPLC purified DNA oligosUltramer DNA Oligos
Typical cross-contamination10.10–0.50%0.01–0.05%
Typical time to shipment25 to 15 business days3 to 10 business days
Synthesis scale100 nmol, 250 nmol, or 1 µmolN/A
Yield deliveredVariable4 nmol or 20 nmol

1 Typical cross-contamination levels were determined using in-house proprietary QC techniques and information from our customers.

2 Production time depends on the number of oligos ordered. Please inquire for an estimated ship date specific to your order.

Compatible modifications

Modification typeModificationDNA oligos
(100 nmol, 250 nmol, 1 µmol)
Ultramer DNA Oligos
(4 nmol, 20 nmol)
5′ modifications5′ 5-Methyl dC
5′ Amino Modifier C12
5′ Amino Modifier C6
5′ Biotin
5′ deoxyInosine
5′ deoxyUridine
5′ Phosphorylation
Internal modificationsInt 5-Methyl dC
Int deoxyInosine
Int deoxyUridine
Int Spacer 18
3′ modifications3′ Amino Modifier
3′ ddC
3′ C3 Spacer
3′ Phosphorylation
Modified bases and bonds2′ O-Methyl RNA bases
Phosphorothioate Bond

OligoAnalyzer™ tool

Identify oligonucleotide properties, including melting temperature, hairpins, dimers and mismatches

UNAFold tool

Perform secondary structure analysis

Dilution Calculator

Find the volume needed to dilute your oligo stock to a lower concentration

Resuspension Calculator

Find the volume needed to resuspend a dry oligo to a desired concentration

Brochures and flyers

TruGrade Flyer (234 KB)
TruGrade Flyer (234 KB)