The Element Cloudbreak Freestyle sequencing kit provides a simplified workflow for sequencing third-party libraries on the AVITI™ System. Cloudbreak Freestyle technology enables circularization on flow cell, with direct loading of linear third-party libraries, and eliminates the need for library conversion steps before sequencing. The absence of PCR amplification in library loading and the polony generation process minimizes the potential for mutations or amplification bias and allows for a complete PCR-free library sequencing workflow.

Figure 1. Workflow comparison of three methods to support sequencing of third-party libraries on the AVITI System

Cloudbreak Freestyle chemistry further enables the compatibility of third-party assays, compared to the Element Adept v1.1 or Rapid PCR-free Workflows. Libraries with missing, additional, or mismatched bases at the ends that block circularization, are now seamlessly compatible with Cloudbreak Freestyle chemistry.

Figure 2. Optimal density achieved with Cloudbreak Freestyle chemistry

Previously, some library types required additional processing when using Cloudbreak for sequencing. Now, when sequenced with Cloudbreak Freestyle chemistry, they produce good density when loaded directly in a linear format (Figure 2; PF Polonies (M) – total pass filter polonies in million).

Examples of these library types include:

  • Standard – Library with intact ends
  • Type 1 – Additional base at 5' end
  • Type 2 – Truncated 1 base
  • Type 3 – Blocked 5’ end

In general, good practice of lab protocol and experiment design contributes to successful sequencing runs and high sequencing quality. For library preparation, we recommend using HPLC purified adapters for reproducibility and a high percentage of full-length oligo synthesis. When a library contains full-length adapters at both 5’ and 3’ ends, it generates consistent ligation yields and will result in good density with Freestyle chemistry (or high circularization yield with Adept workflow).

Assays Requiring Additional Processing

Some library types are not directly compatible or may show variable performance with Cloudbreak Freestyle. If you are preparing libraries using the kits and specified workflows listed in the tables below, please contact Element technical support for assistance.

Table 1. Incompatible assay or workflows

Vendor

Workflow

Kit example

Expected result

Note

IDT

PCR-free

xGen™ UDI-UMI Adapters, 16 rxn, 96rxn

No polonies (PCR-free workflow only)

PCR-plus workflow is compatible

IDT

Enzyme based normalization

xGen™ Normalase™ Module 96rxn

No polonies

Illumina

Bead-based normalization

Nextera XT DNA Library Preparation Kit (24, 96 samples)

TruSight Tumor 170 NextSeq Kit (24 Sample Library Prep Kit)

TruSight Oncology 500 DNA Kit (48 Sample Library Prep Kit Only)

TruSight Oncology 500 DNA/RNA Bundle (24 Sample Library Prep Kit Only)

No polonies

The final library is compatible if it does NOT go through bead-based normalization

Table 2. Assays that may show variable performance

Vendor

Workflow

Kit example

Expected result

Illumina

Library prep workflow with amplification module using "PPC" reagent

Illumina DNA Prep with Enrichment

Illumina RNA Prep with Enrichment (L) Tagmentation

TruSeq ChIP Library Prep

TruSeq DNA Nano

TruSeq RNA Exome

TruSeq RNA Library Prep Kit v2

TruSeq Stranded Total RNA

TruSeq Stranded Total RNA with Ribo-Zero rRNA Depletion

TruSeq Stranded mRNA

TruSight RNA Fusion Panel

TruSight RNA Pan-Cancer

Low or variable density

Custom Sequencing Primers

Cloudbreak Freestyle sequencing cartridges support sequencing of Elevate, TruSeq, and Nextera adapter libraries. Libraries with custom adapter sequences require a spike-in or complete swap of sequencing primers for sequencing. Follow the AVITI user guide for custom sequencing primer purity and concentration requirements to achieve the best sequencing quality.

Update October 1, 2024:

Effective from sequencing cartridge lot number 2409210001 and beyond, Cloudbreak Freestyle cartridges now come pre-loaded with additional Read1, Read2, and Index1 primers compatible with common small RNA adapters. This upgrade ensures direct compatibility and streamlines workflows for assays such as PerkinElmer NEXTFLEX small RNA v3, 10X Genomics Fixed RNA Profiling (Flex), 10x Genomics Visium for FFPE, and Visium HD. This upgrade allows users to omit the previously required primer spike-in when sequencing compatible libraries. All Cloudbreak Freestyle sequencing cartridges including lot # 2409210001 and higher are compatible. See Table 4 below.

Table 3 lists third-party libraries with adapters requiring custom sequencing primers. Please contact technical support of these vendors for adapter sequences.

Table 3. Assays requiring custom sequencing primers

Vendor

Assay Kit

Custom Primer Requirements

10x Genomics

Single Cell Gene Expression Flex

Spike-in corresponding small RNA sequencing primers for Index1 and Read2 primers;
Recent lots of Cloudbreak Freestyle cartridges contain common small RNA adapters and are directly compatible, see below for compatible lot numbers

10x Genomics

Visium Spatial Gene Expression for FFPE

Spike-in corresponding small RNA sequencing primers for Index1 and Read2 primers;

Recent lots of Cloudbreak Freestyle cartridges contain common small RNA adapters and are directly compatible, see below for compatible lot numbers

10x Genomics

Visium HD

Spike-in corresponding small RNA sequencing primers for Index1 and Read2 primers;
Recent lots of Cloudbreak Freestyle cartridges contain common small RNA adapters and are directly compatible, see below for compatible lot numbers

10x Genomics

Libraries with Small RNA adapter for Read 2 – “TS” index set

Spike-in corresponding small RNA sequencing primers for Index1 and Read2 primers;
Recent lots of Cloudbreak Freestyle cartridges contain common small RNA adapters and are directly compatible, see below for compatible lot numbers

Illumina

TruSeq Small RNA Library Prep

Spike-in small RNA sequencing primers for Index1, Read1, and Read2;
Recent lots of Cloudbreak Freestyle cartridges contain common small RNA adapters and are directly compatible, see below for compatible lot numbers

Illumina

Illumina PCR-free Library Prep

Custom sequencing primer for Read1

NEB

NEBNext Small RNA library

Custom sequencing primer for Read1

Revvity

NEXTFLEX Small RNA-Seq Kit v4 with UDIs

Spike-in corresponding small RNA sequencing primers for Index1 and Read2;
Recent lots of Cloudbreak Freestyle cartridges contain common small RNA adapters and are directly compatible, see below for compatible lot numbers

Custom

n/a

Custom sequencing primers accordingly

Table 4: Cloudbreak Freestyle kits updated, by part number

Product
Number

Product Name

Kit updated to include small RNA sequencing primers Read1, Read2, and Index1

860-00014

AVITI 2x75 Sequencing Kit Cloudbreak FS Medium Output

Sequencing cartridge Lot 2409210001 and higher include updated primers

860-00015

AVITI 2x75 Sequencing Kit Cloudbreak FS High Output

Sequencing cartridge Lot 2409210001 and higher include updated primers

860-00011

AVITI 2x150 Sequencing Kit Cloudbreak FS Low Output

Sequencing cartridge Lot 2409210001 and higher include updated primers

860-00012

AVITI 2x150 Sequencing Kit Cloudbreak FS Medium Output

Sequencing cartridge Lot 2409210001 and higher include updated primers

860-00013

AVITI 2x150 Sequencing Kit Cloudbreak FS High Output

Sequencing cartridge Lot 2409210001 and higher include updated primers

860-00016

AVITI 2x300 Sequencing Kit Cloudbreak FS Medium Output

Sequencing cartridge Lot 2409210001 and higher include updated primers

860-00017

AVITI 2x300 Sequencing Kit Cloudbreak FS High Output

Sequencing cartridge Lot 2409210001 and higher include updated primers