Get Help Sign In

eBlocks™ Gene Fragments

Assemble multiple constructs for screening with dsDNA sequences delivered quickly and within budget. These high-quality gene fragments are designed for fast turnaround times and can ship in as little as 1–3 business days from order confirmation.


  • Fast turnaround
  • Minimal screening effort
  • Budget friendly

eBlocks Gene Fragments

Shipped in 1-3 business days of order confirmation (excluding Fridays).
Orders require a minimum of 24 fragments per plate*.


Table 1. Available formats of eBlocks Gene Fragments.

Plate typeBuffer optionVolumeConcentration
96-well PCR PlateNuclease-free water or IDTE pH 8.020 µL10 ng/µL
Dry (no buffer)N/AN/A
384-well PCR PlateNuclease-free water or IDTE pH 8.020 µL10 ng/µL
384-well Echo™ Plate**Nuclease-free water or IDTE pH 8.050 µL4 ng/µL

To achieve the fastest possible shipping time, items that do not meet IDT's purity and yield specifications after the first assembly attempt will be cancelled at no charge. No formal cancellation notice will be sent for these items. However, cancellations will be noted on the item specification sheet, which can be accessed using the Synthetic Biology Order Status Checker.

*Plates with less than 24 fragments will incur an additional fee applied at checkout
**Echo is a trademark of Labcyte Inc. A Beckman Coulter company

Product details

eBlocks Gene Fragments are double-stranded DNA fragments of 300–1500 bp in length that are typically shipped in 1–3 business days. They are uniquely suited for high-throughput screening of multiple constructs.

IDT offers fragments without flanking (i.e., universal adapter) sequences at no extra cost. With no flanking sequences to remove, eBlocks are ready-to-use for various applications.

Table 2. eBlocks Gene Fragment characteristics.

Length300–1500 bp
Median error rate1:5000 bp
Shipping time*1–3 business days
Yield200 ng

* Shipping time refers to the number of business days after order confirmation (excluding Fridays for wet plates). Shipping time is dependent on length and complexity of the eBlocks Gene Fragments ordered. In a few cases, shipping time may exceed the estimated time.

Storage conditions

Short term (<2 weeks)4°C
Long term (up to 2 years)–20°C

Quality control for higher cloning efficiency

Each eBlocks Gene Fragment goes through a quality control process by verifying the size of the fragment by capillary electrophoresis, confirming that most recombinant colonies obtained from cloning contain the desired insert. More complex sequences may require the end-user to sequence additional clones.


Request a consultation

Working on antibody discovery or other high throughput applications you’d like to discuss? Your time is valuable and we’ll prioritize your inquiry. Click on “Request a consultation” to provide brief information about your project, and we’ll be in touch to discuss it ASAP.

Request a consultation

Product data

Minimal screening effort

eBlocks Gene Fragments are compatible with many convenient cloning and assembly kits. eBlocks Gene Fragments reduce the time needed and expense of screening colonies.

The values in Table 3 demonstrate the typical screening requirements when using an isothermal assembly method under optimal conditions.

Table 3. Low screening effort is needed for eBlocks Gene Fragments to have a >90% chance to find the correct clone.

Length (bp)Colonies to pick

Consistent high fidelity

All IDT gene fragments demonstrate a consistent, high sequence fidelity across various lengths, and eBlocks Gene Fragments are no exception (Figures 1 and 2).

Figure 1. In this study, eBlocks Gene Fragments had a higher predicted cloning success compared to fragments supplied by an alternative vendor. eBlocks Gene Fragments have a median error rate of less than 1:5000 bp. This means that eBlocks Gene Fragments demonstrate a high probability of first-time cloning success, indicating that IDT fragments may be more likely to give a correct clone the first time than fragments supplied by the other vendor at comparable length ranges.

Figure 2. eBlocks Gene Fragments demonstrate improved cloning efficiency. Compared to a leading provider, eBlocks Gene Fragments showed a improvement in cloning efficiency, leading to a reduction in the time and cost to find a correct clone.

Across various lengths, IDT gene fragments demonstrated consistent cloning efficiency and cloning fidelity. In a recent head-to-head comparison study, IDT fragments out performed those from another supplier. Read the study to learn more about how DNA synthesis and sequence error correction processes at IDT positively impact fidelity and screening efforts compared to alternative supplier.

Frequently asked questions


Sequence Information is secure and confidential at IDT. Please see our Confidentiality Statement for more information. All online ordering steps, including sequence entry and your choice of parameters, are also secure and protected.

We screen the sequence of every gene, gene fragment, and Megamer™ ssDNA fragment order we receive to (1) identify any regulated and other potentially dangerous pathogen sequences, and (2) verify that IDT’s gene customers are legitimate scientists engaged in beneficial research.

IDT is among the five founding members of the International Gene Synthesis Consortium (IGSC) and helped to create the IGSC’s Harmonized Screening Protocol. The Harmonized Screening Protocol describes the gene sequence and customer screening practices that IGSC member companies employ to prevent the misuse of synthetic genes. IDT takes the steps set out in the Harmonized Screening Protocol to screen the sequences of ordered genes and the prospective customers who submit those orders.

For more information about the IGSC and the Harmonized Screening Protocol, please visit the website at


In October 2010, the United States government issued final Screening Framework Guidance for Providers of Synthetic Double-Stranded DNA, describing how commercial providers of synthetic genes should perform gene sequence and customer screening. IDT and the other IGSC member companies supported the adoption of the Screening Framework Guidance, and IDT follows that Guidance in its application of the Harmonized Screening Protocol. For more information, please see 75 FR 62820 (Oct. 13, 2010), or