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Short answer
FPLC (fast protein liquid chromatography) is a medium-pressure liquid chromatography technique used to purify large biomolecules such as proteins and DNA. A pump sets how fast the mobile phase moves through the column, and a UV detector, a conductivity meter and a fraction collector track and collect what elutes. It differs from analytical HPLC mainly in its column media, its biocompatible wetted parts and its goal: recovering pure, native product.
What FPLC is
Bio-Rad describes FPLC as a medium-pressure liquid chromatography technique in which a pump controls how quickly the mobile phase passes through the stationary phase. Pharmacia introduced it in 1982 under the name “fast performance liquid chromatography”, and the term is often used interchangeably with “medium-pressure chromatography”.
The aim of an FPLC run is different from that of an analytical separation. According to an LCGC International comparison of the two methods, FPLC purifies large biomolecules such as proteins or DNA, and it is applied to proteins, nucleotides and peptides of several kDa, with the goal of obtaining as much pure, native product as possible. For the analytical counterpart, see HPLC vs FPLC; for the wider purification strategy that FPLC steps sit inside, see protein purification.
How an FPLC system and run work
The system modules
Bio-Rad lists the core of a typical FPLC system as a pump, a UV detector, a conductivity meter and a fraction collector. Some systems add further modules:
- column switching valves
- sample pumps
- buffer blending valves, which generate buffer gradients
- multi-wavelength detectors
Bio-Rad states that systems of this kind operate at pressures of about 3,500 psi (24 MPa).
Capture, intermediate and polishing
The LCGC International article describes a typical purification as capture, intermediate and polishing steps, with the separation modes listed below as the methods in use. Because FPLC methods are mostly column-volume based, the LCGC article notes that scaling up is easy.
Separation modes used on FPLC
The LCGC International article names four modes as the main FPLC methods.
| Mode | Notes |
|---|---|
| Size-exclusion chromatography | One of the main FPLC modes |
| Ion-exchange chromatography | One of the main FPLC modes |
| Affinity chromatography | Includes immobilised metal affinity chromatography (IMAC) for His-tagged proteins |
| Hydrophobic interaction chromatography | One of the main FPLC modes |
CASRAI covers two of these in more detail: ion exchange chromatography and gradient choice and hydrophobic interaction chromatography.
Where it matters for labs: what changes compared with HPLC hardware and consumables
The checklist below sets out how FPLC set-up differs from analytical HPLC, following the LCGC International comparison. It describes the techniques; it is not a buying guide.
| Item | FPLC practice (LCGC International) |
|---|---|
| Column media | Agarose or polymer material with bigger particle sizes for most methods |
| Wetted parts | Stainless steel is avoided in favour of biocompatible material such as polyether ether ketone (PEEK), with ceramic and titanium also used; steel can corrode and release metal ions |
| Air bubbles | The media are less pressure-stable and sensitive to air bubbles |
| Column housing | Pressure stability is not important for FPLC, which allows transparent glass columns |
| Buffers | Isosmotic pH and salt concentrations similar to the cell environment are usually chosen |
| Temperature | The working temperature for proteins is usually 4 °C |
Air handling is a topic in its own right on the analytical side; degassing in HPLC covers it for that technique.
Common misunderstandings
“FPLC is just low-pressure HPLC”
Pressure alone does not separate the two. Bio-Rad cites FPLC systems operating at about 24 MPa, and the LCGC comparison locates the practical differences in media (agarose or polymer with larger particles), biocompatible wetted parts, buffers and temperature. Column and media pressure limits vary by product, so no single figure applies to every FPLC column.
“FPLC and HPLC are interchangeable”
They share an origin but are built for different jobs. FPLC is aimed at purifying large biomolecules in their native form; analytical HPLC is aimed at analysis. Metal wetted parts that suit one can be a problem for the other, because steel can corrode and release metal ions.
“FPLC means one particular separation mode”
FPLC describes the instrument platform and pressure regime. Size-exclusion, ion-exchange, affinity (including IMAC) and hydrophobic interaction chromatography can all be run on it.
FAQ
What does FPLC stand for?
Fast protein liquid chromatography. Pharmacia introduced it in 1982 as “fast performance liquid chromatography”, per Bio-Rad.
What are the main parts of an FPLC system?
A pump, a UV detector, a conductivity meter and a fraction collector, with optional column switching valves, sample pumps, buffer blending valves and multi-wavelength detectors (Bio-Rad).
What is FPLC used to purify?
Large biomolecules such as proteins and DNA, including nucleotides and peptides of several kDa (LCGC International).
Why are PEEK parts used in FPLC?
The LCGC article says stainless steel is avoided because it can corrode and release metal ions, so biocompatible material such as PEEK is used instead.
Sources
- Bio-Rad, “Fast Protein Liquid Chromatography”, bio-rad.com, accessed 29 October 2026.
- S. Runde, “FPLC versus Analytical HPLC: Two Methods, One Origin, Many Differences”, LCGC International, 22 August 2016, chromatographyonline.com, accessed 29 October 2026.
