Cytiva SP Sepharose™ and Q Sepharose™ Fast Flow Resins

As you scale up protein purification, you need chromatography media that stay robust from method development to production. Cytiva’s SP Sepharose™ Fast Flow and Q Sepharose™ Fast Flow resins are long-established ion exchange workhorses based on a 6% cross-linked agarose matrix, designed for high flow rates, reliable binding, and straightforward scale-up in both research and industrial downstream processes.

Overview of Sepharose™ Fast Flow Ion Exchange Resins

A clear understanding of what sits inside your columns makes it easier to select the right media for each purification step. In this section, you’ll see how the Sepharose Fast Flow platform underpins both SP and Q resins, what they share in common, and why they’re still widely used as an industry standard for ion exchange chromatography.

Sepharose Fast Flow ion exchangers are built on a hydrophilic 6% agarose bead with a particle size around 45–165 µm, balancing capacity and pressure/flow performance for packed bed columns. Within this platform:

• SP Sepharose Fast Flow carries sulphopropyl (SP) strong cation exchange ligands for binding positively charged proteins.

• Q Sepharose Fast Flow carries quaternary amine (Q) strong anion exchange ligands for negatively charged biomolecules.

Both resins offer:

• High dynamic binding capacity over a broad working pH range

• Chemical stability compatible with standard CIP and sanitization schemes

• Good scalability from lab columns to large-scale process columns

How Ion Exchange Chromatography with Sepharose Fast Flow Works

Before you choose between SP and Q Sepharose Fast Flow, it helps to reconnect the resin choice to the fundamentals of ion exchange chromatography. This section summarizes how pH, protein pI, and salt concentration influence binding, so you can map your targets and impurities to the right ion exchanger more confidently.

In ion exchange chromatography, charged ligands on the resin interact with oppositely charged groups on the solute:

• Cation exchangers (like SP Sepharose Fast Flow) are negatively charged and bind positively charged proteins.

• Anion exchangers (like Q Sepharose Fast Flow) are positively charged and bind negatively charged proteins.

Key parameters you control are:

• Buffer pH vs protein pI – proteins are positively charged at pH below their pI and negatively charged above their pI.

• Salt concentration – low salt for binding, increasing salt (or pH change) for elution.

• Residence time and flow rate – adjusted to balance binding capacity and throughput.

With Sepharose Fast Flow resins, you can usually run at 50–400 cm/h working flow rates and still maintain good performance, making them suitable for capture and intermediate purification steps.

SP Sepharose™ Fast Flow: Strong Cation Exchange for Positively Charged Targets

When your target carries a net positive charge at the chosen pH, SP Sepharose Fast Flow is often the first cation exchanger to consider. Here you’ll see how its sulphopropyl ligand, binding profile, and operating window support robust capture and intermediate purification of many biopharmaceutical proteins.

SP Sepharose Fast Flow is a strong cation exchanger with a sulphopropyl group covalently attached to the 6% agarose matrix. It maintains its charge across a broad pH range and offers a total ionic capacity of around 0.18–0.25 mmol H⁺/mL of packed resin, supporting high binding capacities for basic proteins.

For your processes, this means you can:

• Bind positively charged proteins (for example, many enzymes and basic recombinant proteins) at pH values below their pI.

• Operate within a typical working pH window of about 4–13, with CIP procedures extending from pH 2 up to ≥12 as required.

• Take advantage of the resin’s hydrophilic base matrix to reduce non-specific hydrophobic interactions and host-cell impurity carryover.

Typical use cases include:

• Capture of basic monoclonal antibody fragments or Fc-containing proteins after clarification

• Intermediate purification of enzymes where you need good capacity at high flow rates

• Polishing of positively charged impurities left after affinity or mixed-mode steps

Q Sepharose™ Fast Flow: Strong Anion Exchange for Negatively Charged Targets

When your molecule of interest is negatively charged, or when you want a polishing step to remove anionic impurities, Q Sepharose Fast Flow is the natural counterpart to SP. In this section, you’ll see how its quaternary amine ligand and pH range support both capture and polishing of many acidic proteins, plasma components, and nucleic acid-containing feeds. 

Sepharose Fast Flow is a strong anion exchanger with quaternary amine ligands on the same 6% agarose backbone used across the Fast Flow platform. It maintains a positive charge throughout its working pH range (typically pH 2–12), enabling stable binding of negatively charged biomolecules under many buffer conditions.

In practice, you can:

• Bind acidic proteins, many plasma proteins, and DNA/RNA-containing impurities at pH above their pI.

• Use the resin as a capture step for negatively charged targets or as an anion exchange polish to reduce host cell protein, DNA, and endotoxin levels.

• Run at similar flow rates to SP Sepharose Fast Flow, simplifying column hardware selection and scale-up across both cation and anion steps.

How to Choose Between SP and Q Sepharose Fast Flow

With both cation and anion exchangers available on the same Fast Flow platform, the critical question is which one to use in your specific workflow. This section links common purification scenarios to SP or Q selection so you can design a sequence of steps that matches your molecule’s charge and impurity profile.

At a simple level:

• If your target is positively charged under process conditions, you usually choose SP Sepharose Fast Flow.

• If your target is negatively charged, or you mainly want to remove negatively charged impurities, Q Sepharose Fast Flow is preferred.

A quick decision guide you can use during method development:

Scenario	Typical pH vs pI	Recommended resin	Role in workflow
Basic protein capture (pI > process pH)	pH < pI (target +)	SP Sepharose Fast Flow	Capture/intermediate
Acidic protein capture (pI < process pH)	pH > pI (target –)	Q Sepharose Fast Flow	Capture/intermediate
DNA, endotoxin, and acidic impurity removal after capture	pH > impurity pI	Q Sepharose Fast Flow	Polishing/impurity removal
Removal of basic impurities after affinity or AEX	pH < impurity pI	SP Sepharose Fast Flow	Polishing

By starting from the target pI and buffer pH, you can quickly shortlist one resin, then fine-tune salt gradients, flow rates, and load densities to balance purity, yield, and productivity.

Integrating Sepharose Fast Flow Resins into Your Purification Workflow

Once you know which resin you need, the next step is to place it correctly in your multi-step process. This section outlines how SP and Q Sepharose Fast Flow can sit alongside affinity, hydrophobic interaction, and mixed-mode steps, helping you design a sequence that is both scalable and regulatory-friendly.

You can typically integrate these resins in three main roles:

• Capture: Use SP or Q Sepharose Fast Flow as the first binding step after clarification when you want high capacity and robust flow properties, especially for high-volume feeds.

• Intermediate purification: Combine a Fast Flow step with affinity or mixed-mode chromatography to separate product from closely related variants and process contaminants.

• Polishing: Run Q or SP in flow-through or bind-and-elute mode to tighten specifications for host-cell proteins, DNA, aggregates, or charge variants.

Because both resins can be packed in standard process columns and withstand typical cleaning-in-place regimes, they also fit well with automated systems such as ÄKTA™ platforms, allowing you to transfer methods from development to manufacturing with minimal re-optimization.

Popular SP & Q Sepharose Fast Flow SKUs and Specifications

When it comes to ordering, you need clear, accurate catalog numbers that match Cytiva’s official product list. This section highlights commonly used bulk media packs for SP and Q Sepharose Fast Flow, together with their pack sizes and ion exchange type, so you can link your internal SKU mapping directly to Cytiva part numbers.

Product	Ion exchange type	Pack size	Cytiva catalog no.	Typical use case
SP Sepharose Fast Flow	Strong cation (SP)	25 mL	17-0729-10	Method development / small-scale optimization
SP Sepharose Fast Flow	Strong cation (SP)	300 mL	17-0729-01	Pilot and small production columns
Q Sepharose Fast Flow	Strong anion (Q)	25 mL	17-0510-10	Method development/screening
Q Sepharose Fast Flow	Strong anion (Q)	300 mL	17-0510-01	Pilot and small production columns

These code numbers and pack sizes follow Cytiva’s official ordering information for Q and SP Sepharose Fast Flow bulk media.

Key technical characteristics you’ll typically work with include:

• Matrix: 6% cross-linked agarose, spherical beads

• Particle size: ~45–165 µm (average ~90 µm in many specifications) 

• Working pH: approx. 4–13 for SP Sepharose Fast Flow and 2–12 for Q Sepharose Fast Flow, with similar or wider ranges for cleaning-in-place.

You can build your own IEX collection table around this core set, linking each Cytiva part number to your internal SKU, packaging, and stock status.

Application Highlights with SP and Q Sepharose Fast Flow

Real-world examples make it easier to picture where these resins will sit in your own pipeline. This section summarizes a few typical application patterns so you can map them to your antibody, vaccine, plasma, or enzyme projects and quickly decide where Sepharose Fast Flow fits best. 

A few common patterns you might follow are:

• Antibody or Fc-fragment purification: Use Protein A or other affinity resin for capture, followed by SP or Q Sepharose Fast Flow to separate charge variants and reduce host-cell proteins in an economical, high-capacity step. 

• Enzyme and recombinant protein processes: Apply SP Sepharose Fast Flow as a capture step for basic enzymes, then polish on Q Sepharose Fast Flow to remove DNA and acidic impurities.

• Plasma and vaccine workflows: Use Q Sepharose Fast Flow to capture or polish negatively charged plasma proteins or virus-like particles, taking advantage of its broad pH range and compatibility with large columns. 

By combining these ion exchange steps with affinity, hydrophobic interaction, or mixed-mode resins, you can design modular workflows that are easier to scale and adjust as your process evolves.