Cytiva ÄKTA flux s Tangential Flow Filtration System

Overview

The Cytiva ÄKTA flux s is a compact, benchtop tangential flow filtration (TFF) system engineered for precision sample concentration, buffer exchange (diafiltration), cell harvest, and clarification in early-stage bioprocessing and membrane screening workflows. Operating on the principle of cross-flow filtration—where feed stream velocity is maintained parallel to the membrane surface—the system minimizes concentration polarization and fouling, enabling reproducible recovery of labile biomolecules including monoclonal antibodies, viral vectors, plasmid DNA, and exosomes. Its modular architecture integrates seamlessly with Cytiva’s broader ÄKTA platform ecosystem, particularly as a pre- or post-chromatography unit in protein purification trains. The system supports both single-use cassettes (e.g., Cytiva Capto™ Core, Sartorius Viresolve® Pro) and hollow-fiber modules (e.g., Spectrum Labs MiniKros, Repligen KrosFlo® KR2i), allowing method scalability from discovery through process development.

Key Features

• Compact footprint (450 × 400 × 380 mm) optimized for biosafety cabinets and shared lab spaces
• Automated endpoint control via real-time transmembrane pressure (TMP), permeate flux, and retentate volume feedback loops
• Constant Retentate Volume (CRV) mode for precise volumetric control during diafiltration—critical for maintaining protein stability and minimizing shear stress
• Integrated peristaltic pump with pulse-dampening technology and calibrated flow range of 0.1–200 mL/min (accuracy ±2% of setpoint)
• 7-inch capacitive touchscreen running Cytiva’s UNICORN-based firmware (v8.2 or later), supporting intuitive protocol creation, parameter logging, and alarm management
• Onboard data storage (≥10,000 events) with timestamped audit trail, CSV export via USB, and optional Ethernet connectivity for networked lab environments

Sample Compatibility & Compliance

The ÄKTA flux s accommodates a broad range of biological feedstreams—from clarified mammalian cell culture harvests (up to 20% v/v solids) to bacterial lysates and insect cell supernatants. It accepts standard TFF consumables with molecular weight cut-offs (MWCO) spanning 1 kDa to 0.2 µm, including regenerated cellulose, polyethersulfone (PES), and polyvinylidene fluoride (PVDF) membranes. All wetted parts are USP Class VI-certified and compatible with common cleaning-in-place (CIP) agents (e.g., 0.5 M NaOH, 20% ethanol). The system conforms to IEC 61010-1 safety standards and supports alignment with GMP/GLP documentation requirements when used with UNICORN’s electronic signature and audit-trail modules compliant with FDA 21 CFR Part 11.

Software & Data Management

Control and data acquisition are managed through an embedded version of Cytiva UNICORN software, tailored for TFF-specific operations. Users define multi-step methods—including feed loading, concentration ramping, diafiltration cycles, and final flush—with programmable logic for conditional transitions (e.g., “proceed to step 2 when retentate conductivity drops below 5 mS/cm”). All operational parameters (TMP, flux, volume, temperature) are logged at user-defined intervals (1–60 sec), with metadata automatically appended (operator ID, method name, timestamp). Data files are stored in standardized CSV format, enabling direct import into LIMS or statistical analysis platforms such as JMP or Python pandas. Optional integration with Cytiva’s Bioprocess Control System (BPCS) enables centralized monitoring across multiple ÄKTA instruments.

Applications

• Early-stage membrane screening for optimal MWCO selection and flux characterization
• Concentration of low-titer recombinant proteins prior to ion-exchange or affinity chromatography
• Gentle diafiltration of AAV vectors into formulation buffers without aggregation
• Clarification of high-viscosity CHO harvests using 0.2 µm microfiltration cassettes
• Process development support for scalable TFF protocols aligned with ÄKTA flux 6 and production-scale systems
• Training platform for TFF fundamentals in academic and contract research organizations (CROs)

FAQ

What is the minimum working volume supported by the ÄKTA flux s?
The system operates reliably down to 10 mL retentate volume, with CRV control active from 20 mL onward.
Can the ÄKTA flux s be used with non-Cytiva membranes?
Yes—provided mechanical compatibility (e.g., cassette housing dimensions, port threading) and chemical resistance are verified; users must validate performance and cleaning protocols independently.
Does the system support remote monitoring or integration with SCADA?
Native remote access is not available; however, Ethernet-enabled data export and OPC UA-compatible third-party gateways may be deployed via custom configuration.
Is validation documentation (IQ/OQ) included with the instrument?
Factory-issued IQ/OQ templates are provided; site-specific execution requires qualified personnel and adherence to internal SOPs.
How frequently does the peristaltic pump tubing require replacement?
Under typical use (≤8 hrs/day, aqueous buffers), silicone tubing should be replaced every 3–6 months or after 500 operating hours—whichever occurs first.