NEBNext Ultra II FS DNA Library Prep for Illumina

Increase your Library Prep efficiency with the NEBNext Ultra II DNA Fragmentation System Kits

NEBNext® Ultra™ II kits are designed for construction of high-quality libraries using a broad range of input amounts, from pg to µg of DNA. The workflows are fast, streamlined and automatable, with flexible product formats to enable customization.

With our latest kits, we have built upon our NEBNext Ultra II DNA library prep workflow to create a fragmentation system, the NEBNext Ultra II FS DNA Library Prep Kit. The Ultra II FS kit includes a new DNA fragmentation reagent, which is also combined with end repair and dA-tailing reagents, enabling these steps to be performed in the same tube, with no clean-ups or sample loss. The same fragmentation protocol is used for any input amount (100 pg–500 ng), or GC content.

You’ll be thrilled to pieces with the result – a reliable, flexible, high-quality library prep that is fast and scalable.

Video: Preparing an Ultra II FS DNA Master Mix


  • Perform fragmentation, end repair and dA-tailing with a single enzyme mix
  • Experience reliable fragmentation with a single protocol, regardless of DNA input amount or GC content
  • Prepare high quality libraries from a wide range of input amounts: 100 pg–500 ng
  • Generate high yields with increased reaction efficiencies and minimized sample loss
  • Use with DNA in standard buffers (TE, Tris-HCl) and water
  • Save time with a streamlined workflow: ~ 2.5 hours, with < 15 minutes hands-on time
  • Vary incubation time to generate a wide range of insert sizes
  • Available with optional SPRIselect® beads for size selection/clean-up

Get a free NEBNext Ultra II FS Library Prep Kit sample!

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What people are saying about the NEBNext Ultra II FS Kit

„The Wellcome Trust Sanger Institute currently processes thousands of DNA samples each month via its core DNA sequencing library construction pipelines. However, a recent requirement to generate high quality whole genome and targeted sequencing data from biopsy material led us to develop and implement a novel workflow enabled by NEBNext Ultra II FS. Our new automated workflow, coupled with the high efficiency of the NEBNext Ultra II FS reagent, is allowing us to routinely generate deep sequence data from as few as 100-1000 human cells.“

Dr. Peter Ellis Senior Staff Scientist, R&D Sequencing, Wellcome Trust Sanger Institute

„NEBNext Ultra II FS performance is exceptional. The possibility to start with higher DNA concentrations allows for less consumption of reagents for initial QC. Obtaining the desired fragment length and less hands-on time are also key factors when preparing genomic libraries and NEBNext Ultra II FS can provide that. The use of fewer PCR cycles also decreases the bias associated with the PCR step.“

João Anes, Ph,D., NGS specialist in Food Safety, UCD-Centre for Food Safety, Dublin, Ireland

„I don’t know of any other NGS library prep kit that works so well with small genomes/DNA fragments e.g. bacterial, phage genomes, plasmids, PCR products.“

Anton Bryksin, Ph.D., Director, Molecular Evolution Core, Parker H. Petit Institute for Bioengineering and Bioscience

„In our core, we process large number of samples for genomics applications. Even with the high-throughput Covaris® model, the sample shearing is still a bottle neck for us. The NEBNext DNA Ultra II FS DNA kit is such a wonderful product. First of all, it increased our throughput dramatically for DNA sample shearing. The kit combines the shearing, end-repair, dA-tailing, and linker-ligation in a couple simple steps without the need of purification in between. The whole process has been reduced from two days to a few hours. Second, we love the low input option. Because the kit eliminates the need for purification for each of the intermediate steps, it reduces a lot of sample loss during the purification steps, which enables us to use much less starting materials and saves tons on purification beads. Third, we are amazed by the randomness of the enzymatic shearing. We did not observe any significant difference from mechanical shearing. We have used this kit successfully with many large projects including high-throughput genomic screening assays.“

Scientist, Cancer research institute

„This kit is fantastic! I was able to create a high quality genomic library from 200 pg of DNA using the NEB Ultra II FS Kit. I had a non-model organism, limited material, GC bias and no experience with genomic library prep. The enzymatic fragmentation meant I didn’t lose any precious material in shearing and I was more than happy with the yield.“

Dr. Ashlie Hartigan, Kings College London

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NEBNext® for Illumina – NGS Sample Preparation


Feature Article:

„Improving Enzymatic DNA Fragmentation for Next Generation Sequencing Library Construction“

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NEBNext Ultra II FS DNA produces the highest yields, from a range of input amounts

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Libraries were prepared from Human NA19240 genomic DNA using the input amounts and numbers of PCR cycles shown. For NEBNext Ultra II FS, a 20-minute fragmentation time was used. For Kapa HyperPlus libraries, input DNA was cleaned up with 3X beads prior to library construction, as recommended, and a 20-minute fragmentation time was used. Illumina recommends 50 ng input for Nextera, and not an input range; therefore, only 50 ng was used in this experiment. “Covaris” libraries were prepared by shearing each input amount in 1X TE Buffer to an insert size of ~200 bp using a Covaris instrument, followed by library construction using the NEBNext Ultra II DNA Library Prep Kit (NEB #E7645). Error bars indicate standard deviation for an average of 3–6 replicates performed by 2 independent users.

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Available NEBNext Ultra II FS products

NEBNext® Ultra™ II FS DNA PCR-Free Library Prep Kit for Illumina® E7430S 24 rxns 672 € In den Shop wechseln Produktinformationen
E7430L 96 rxns 2.548 € In den Shop wechseln Produktinformationen
NEBNext® Ultra™ II FS DNA PCR-Free Library Prep Kit for Illumina® with Beads E7435S 24 rxns 736 € In den Shop wechseln Produktinformationen
E7435L 96 rxns 2.782 € In den Shop wechseln Produktinformationen
NEBNext® Ultra™ II FS DNA Library Prep Kit for Illumina® E7805S 24 rxns 708 € In den Shop wechseln Produktinformationen
E7805L 96 rxns 2.690 € In den Shop wechseln Produktinformationen
NEBNext® Ultra™ II FS DNA Library Prep with Beads E6177S 24 rxns 776 € In den Shop wechseln Produktinformationen
E6177L 96 rxns 2.932 € In den Shop wechseln Produktinformationen
NEBNext® Ultra™ II FS DNA Module E7810S 24 rxns 308 € In den Shop wechseln Produktinformationen
E7810L 96 rxns 1.100 € In den Shop wechseln Produktinformationen

As of: 01.01.2023

NEBNext products are available at a permanent low price that can not be further discounted.

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