KAPA Adapters
for Illumina Sequencing

KAPA Unique-Dual Indexed (UDI) Adapters and KAPA Dual-Indexed (DI) Adapters

Both KAPA UDI Adapters and KAPA DI Adapters contain standard Illumina adapter backbones and are readily incorporated into sequencing workflows for Illumina sequencers. KAPA UDI Adapters employ 192 non-redundant barcodes for the 96 unique dual-index combinations, whereas KAPA DI Adapters offer a combinatorial approach (twelve i7 x eight i5 barcodes = 96 dual index combinations).

All KAPA Adapter Kits: 

  • Enable a broad range of library pooling, from 2-plex up to 96-plex ─ for whole-genome (with or without PCR), whole-transcriptome, or target-enriched sequencing
  • Support paired-end sequencing on 2- and 4-channel Illumina instruments
  • Yield high library conversion efficiency with minimal adapter-dimer formation
  • Are compatible with KAPA HyperPrep, KAPA HyperPlus, KAPA RNA HyperPrep, and HyperCap Target Enrichment workflows
  • Undergo rigorous sequencing-based QC testing


Choose between unique or combinatorial dual-indexed adapters based on your sequencing instrument and the sensitivity of your application to index mis-assignment

Newer Illumina sequencers can be prone to on-instrument index hopping and might incorrectly assign some reads to incorrect adapter. Unique dual-indexing enables the removal of these leads prior to analysis, improving data quality by enhancing read alignment (1,2) and making KAPA UDIs the best choice for those platforms (Table 1). On any Illumina platform, KAPA UDIs can also reduce the impact of incorrect read assignments resulting from barcode or sample cross-contamination during library prep or from template switching during PCR amplification of pooled samples.

Refer to this table to determine whether KAPA UDI Adapters or KAPA DI Adapters are best for your application.

  1. https://www.illumina.com/science/education/minimizing-index-hopping.html. Accessed February 2019.
  2. Costello M, et al. BMC Genomics. 2018;19:332
Table 1. Adapter recommendation based on sequencing platform    


NovaSeq, HiSeq X, HiSeq 3000, HiSeq 4000, or any other Illumina sequencers with patterned flow cells

MiSeq 3000, NextSeq 400, HiSeq 2500, or any older Illumina instruments with non-patterned flow cells


Only KAPA Unique Dual-Indexed (UDI) Adapters

Use KAPA Unique Dual-Indexed (UDI) Adapters, but KAPA Dual-Indexed (DI) Adapters would also suffice