Membrane Range

Transforming Polymer Manufacturing Through Membrane Innovation

Exact‑10, Exact‑01™ and Exact‑20™ are Exactmer's organic solvent nanofiltration (OSN) membranes, each tuned to a different molecular weight cut‑off for a different stage of oligonucleotide synthesis and other pharmaceutical manufacturing applications.

VideoSee the membranes in action

Where each membrane fits

UpstreamSynthesis UpstreamSolvent recovery DownstreamPurification
10

Exact‑10™

Membranes for Liquid Phase Synthesis
Designed for Nanostar Sieving · upstream synthesis
Exactmer’s Exact-10™ membrane is a key component of Exactmer's Nanostar Sieving platform for the synthesis of sequence-defined polymers. Designed specifically for iterative liquid-phase synthesis, the membrane combines high selectivity with excellent stability in organic solvent systems. This provides efficient purification at every synthesis cycle enabling the production of high purity polymers.
  • Stable in acetonitrile, methanol, DMF, NMP
  • Fouling resistant
Approx. 2 kDa molecular weight cut‑off
Explore the Nanostar Sieving® process →
01

Exact‑01™

Solvent Recycling Membranes
High solute rejection · solvent recovery
Exactmer’s Exact-01™ membrane offers high solute rejection for solvent purification and recycling, cutting solvent costs, simplifying handling and minimising waste. By avoiding energy-intensive processes such as distillation, it improves pharmaceutical sustainability. Combined with our Nanostar Hub innovation, enabling more concentrated reactions, Exactmer’s membranes reduce solvent use in oligonucleotide synthesis, particularly for short oligo fragments (5-10mer) used in convergent synthesis.
  • Stable in polar protic & aprotic solvents
  • Reduces solvent use
Approx. 0.2 kDa molecular weight cut‑off
20

Exact‑20™

TFF Membranes for Downstream Processing
Optimised for TFF · downstream purification
Exactmer's OSN membrane innovation extends to downstream processing, streamlining the purification of oligonucleotides and complex molecules. Exact‑20™ is optimised for Tangential Flow Filtration (TFF) in aqueous‑organic solvent mixtures, suited to solvent exchange, impurity removal, and concentration of reaction mixtures and chromatography eluents. Exactmer's bespoke membrane modification processes ensure low fouling and high selectivity, delivering efficient, scalable purification and improved yield.
  • Stable in acetonitrile, methanol, DMF, NMP
  • High concentration filtration
Approx. 2 kDa molecular weight cut‑off

One membrane, every scale

From early-stage evaluation to full manufacturing, our membranes are available in formats built for each stage of development.

FS
R&D · Evaluation

Flat Sheets

Compact, low-volume format ideal for initial screening, process development and early-stage evaluation work before committing to larger-scale trials.

From 0.1 m² membrane area
SW
Manufacturing · Scale-up

Spiral Wound Modules (SWMs)

Our membranes rolled into a high-density, industrially proven format built for medicines manufacturing and large-scale, continuous processing.

Up to 30 m² membrane area
The Format

What is a Spiral Wound Module (SWM)?

A Spiral Wound Module is built from multiple membrane sheets, each separated by two types of spacer: a feed spacer, which keeps the sheets apart and helps material flow evenly across the membrane surface, and a permeate spacer, which channels the filtered liquid away. These layers are glued together into “leaves” and rolled around a central tube to form the finished module.

30× more membrane area than a crossflow cell. Rolling the membrane this way packs far more surface into a small space, taking a process from lab scale to full production.

This scale-up approach is proven and widely used, including across the desalination industry. We apply the same fabrication process to build Nanostar Sieving® membranes as SWMs, ready for commercial manufacturing.

Spiral Wound Module diagram showing feed spacer, membrane, and permeate spacer layers rolled around a central tube

The Mechanism

How OSN separation works

Applied pressure drives the process across the membrane, separating molecules purely by size. Because separation is based on size, the same mechanism underpins Exactmer's entire membrane range, from synthesis to purification to solvent recovery.

Diagram showing Organic Solvent Nanofiltration (OSN) membrane separation: retentate and permeate either side of the membrane
Large molecules (the growing oligo) are retained by the membrane.
Small molecules (monomers and reaction debris) permeate through.
Let's Build Together

Not sure which membrane fits your process?

Talk to our team about evaluation programmes, technical batches, and partnership routes across the Exact range.

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