Flow Cell Wash Kit XL

The Flow Cell Wash Kit provides the reagents required to wash and reuse MinION™ and PromethION™ Flow Cells on a higher scale.

This is compatible with all DNA sequencing kits.

  • Products from Oxford Nanopore Technologies that have completed their Early Access
  • Users can continue to provide feedback through feature request pinboard
  • Warranty periods extended to 1 – 3 months
  • Product continues to iterate with upgrade notifications of up to 3 months
  • Lead time visible in store
  • Product subject to availability


This kit is recommended for users who:

  • Want to wash flow cells and rerun with fresh samples.
  • Wish to run samples on demand, rather than batching samples.
  • Have accumulated a high number of "unavailable" pores during a previous run and wish to revert these pores to the "single pore" state.

The Wash Kit features:

Associated protocolsFlow Cell Wash Kit (EXP-WSH004 or EXP-WSH004-XL)
Associated kitsAll sequencing kits
Pack size48 reactions

Nanopore technology allows for real-time assessment of sequencing experiments with the visualisation of run statistics on the instrument user interface via the MinKNOW user interface. This allows users to run a flow cell until sufficient data has been collected to fulfill the experimental requirements, at which point the run an be stopped. The Flow Cell Wash Kit provides a highly effective means of removing a library that has been loaded onto a flow cell. Once the library has been removed, the flow cell can be re-used immediately, or stored for later usage. The washing procedure is a simple two-step process and the kit contains sufficient reagents to perform 48 flow cell washes.

The Flow Cell Wash Kit XL (EXP-WSH004-XL) is based on the use of a nuclease to digest and remove nucleic acid that has been loaded on to the flow cell. The washing procedure is very effective, with as little as 0.1% of any previously loaded sample contaminating a subsequent run. However, as some contamination from the previous sample may be observed after using the Flow Cell Wash Kit, it is recommended that when running multiple samples sequentially, the samples are barcoded to allow filtering of sequences from the remnants of previously run samples.

Figure 1

Figure 1. A sample with four barcodes was sequenced before the flow cell was washed using EXP-WSH004-XL and a sample with four different barcodes was loaded. This was repeated for a third sequencing run. We repeated process across 4 different flow cells.

After nuclease treatment, and before storing or re-loading the flow cell, the nuclease is inactivated to prevent residual activity impacting future flow cell runs: we do not routinely observe any deterioration in read lengths in sequencing runs performed after the washing procedure.


Figure 2. The nuclease is efficiently inactivated before re-using or storing the flow cell. A sequencing library was prepared, and part of the library was loaded on to a flow cell (load #1). After a period of time, the run was stopped and a wash performed. The flow cell was re-loaded with more of the same library and the experiment re-started (load #2). The washing and re-loading steps were repeated (load #3). No difference in read length distributions was observed for the 3 library loads, suggesting very little residual nuclease activity is present after inactivation.

Increasing flow cell output with the Flow Cell Wash Kit

In sequencing experiments where an accumulation of pores in the “recovering” state (“unavailable” in the detailed view) is observed, the rate of data acquisition drops as fewer pores are available to accept and sequence strands. We have shown that in these circumstances, pores can be reverted to the “single pore” state by performing the washing procedure.


Figure 3. A MinION flow cell has been loaded with a sequencing library that has resulted in an accumulation of channels in the “unavailable” state, leading to a decrease in the rate of data acquisition: after 18 hours, the flow cell has <200 single pores available for sequencing from a starting point of ~1600. A washing procedure was then performed after and the number of single pores increased to ~1000, with a significant number of the channels that had been lost to the “unavailable” state reverting to the “single pore” state.

In experiments where output is limited by the increase in pores in the “recovering”/“unavailable” state, we have shown that output can be at least doubled by performing several wash steps over the lifetime of a flow cell.


Figure 4. Output observed from sequencing libraries run on a PromethION flow cell. The arrows indicate the timing of each wash step: wash steps were performed at the point where the rate of data acquisition started to slow due to the accumulation of “unavailable” pores. In each case, output is more than doubled from the point of the first wash.

Re-loading washed flow cells with the same library will require additional reagents contained within the Sequencing Auxiliary Vials Expansion (EXP-AUX001 or EXP-AUX110).

Shipping and logistics:

Flow cells and kits are shipped together in an environmentally friendly temperature-controlled shipping box.

Products are shipped to customers within the USA and EU Monday to Thursday. Shipments to Canada, Norway, Korea and Japan are expedited Monday to Wednesday; with Australia and New Zealand leaving our warehouses on a Friday. Shipments to the rest of the world are made on Mondays to allow the full working week for packages to arrive.

The delivery charges are calculated when a quote is raised or during checkout. Once an order is made, the delivery ID and delivery information can be tracked in the Store.


  • Shipped at 2–8°C
  • Long-term storage -20°C
  • Oxford Nanopore Technologies deem the useful life of the product to be 3 months from receipt by the customer

What's in the box

EXP-wsh004-XL tubes

NameAcronymFill volume per vial (µl)Cap colourNo. of vialsNo. of uses
Wash MixWMX150Brown148
Wash DiluentDIL20,000Clear cap, brown label148
Storage BufferS25,000Brown cap, yellow label148


The Flow Cell Wash Kit can be used together with:


All Oxford Nanopore DNA sequencing kits

Flow cells

  • FLO-MIN106D
  • FLO-MIN114
  • FLO-PRO002
  • FLO-PRO114M


  • MinION Mk1B
  • MinION Mk1C
  • GridION
  • PromethION