What Is Centrifugal Partition Chromatography?

Centrifugal partition chromatography, or CPC, is a preparative chromatographic technique based on liquid-liquid partitioning. It does not use silica, C18, resin, or any other packed solid stationary phase. Instead, CPC uses two immiscible liquid phases.

One liquid phase is retained inside a rotating rotor. The other liquid phase is pumped through it. As the sample moves through the system, each compound repeatedly distributes between the two liquids. Compounds that prefer the mobile phase move faster. Compounds that spend more time in the retained liquid phase move more slowly.

This is the key technical point behind CPC. It is chromatography, but not the kind most HPLC users first imagine. The stationary phase is not a solid. It is a liquid.

That is also why László Frici Németh and the LiLiChro team often explain CPC through the language of liquid-liquid chromatography. “Centrifugal partition chromatography” is scientifically correct, but it can hide the most important idea: the separation happens between two liquid phases.

What Is Liquid Chromatography?

Liquid chromatography is a separation method where the mobile phase is a liquid. In classical LC and HPLC, the mobile liquid carries the sample through a stationary phase, which is often a packed solid material.

The basic chromatographic idea is simple. A mixture separates because its components distribute differently between:

• a mobile phase that moves
• a stationary phase that stays in place

IUPAC defines chromatography as a separation method where components distribute between two phases, one stationary and one mobile.

In HPLC, the stationary phase is usually a solid packed column. The method developer thinks about column chemistry, particle size, pore size, pressure, gradients, and detector response.

CPC keeps the chromatographic principle but changes the physical system.

What Is Liquid-Liquid Chromatography?

Liquid-liquid chromatography is chromatography where both phases are liquids. One liquid acts as the stationary phase, and the other acts as the mobile phase.

This changes the central method-development question.

HPLC asks: “How does the compound interact with the solid stationary phase and the liquid mobile phase?”

LLC asks: “Which liquid phase does the compound prefer, and by how much?”

That preference is described by the partition coefficient. If the target compound and impurities distribute differently between the two phases, separation becomes possible. If everything stays in the same phase, CPC will not help much.

This is why CPC often feels close to extraction. A separatory funnel also separates compounds by liquid-liquid partitioning. The difference is that CPC organizes this repeated partitioning into a controlled chromatographic process.

As Frici often frames it, CPC may be easier to understand if you first think like an extraction chemist, then return to chromatography.

How Centrifugal Partition Chromatography Works

A CPC system contains a rotor with many interconnected cells. The rotor is filled with one liquid phase, which becomes the stationary phase. Centrifugal force helps retain that liquid inside the rotor while the second liquid phase is pumped through as the mobile phase.

The sample is introduced into the mobile phase. Inside the rotor, the sample repeatedly contacts the retained stationary liquid phase. Each compound partitions between the two liquids many times.

The result is differential migration through the system.

A compound with stronger affinity for the mobile phase elutes earlier.
A compound with stronger affinity for the stationary liquid phase elutes later.
A compound with balanced partitioning may separate well if impurities behave differently.

This is why solvent-system selection is not a side detail in CPC.

A good CPC method depends on:

• two cleanly separating immiscible liquid phases
• useful partition coefficients for target and impurities
• good sample solubility
• stable phase retention
• acceptable pressure and flow behavior
• practical solvent compatibility for the industry and application

CPC is often described as support-free liquid-liquid chromatography because no solid support is used as the stationary phase.

CPC vs HPLC: The Technical Difference

CPC becomes interesting when the purification problem is driven by recovery, complex matrices, adsorption issues, or the need to tune selectivity through solvent-system design rather than packed column chemistry.

Main Industries Using CPC

Pharma

Pharmaceutical R&D often deals with impurities, degradation products, intermediates, APIs, and natural-product-derived molecules. CPC may be relevant when preparative purification is difficult because of adsorption, poor recovery, or complex impurity profiles.

Discover real-world applications of CPC at our pharmaceutical subpage.

Biotech

Biotech workflows may involve fermentation-derived compounds, metabolites, peptides, or sensitive small molecules. CPC can be considered when liquid-liquid partitioning gives a useful separation and the solvent system is compatible with the compound.

Botanicals and Natural Extracts

Plant extracts are chemically crowded. Pigments, terpenes, alkaloids, polyphenols, glycosides, lipids, and related compounds may appear in the same crude material. CPC is useful to investigate here because solvent systems can be tuned around compound families.

Cannabis

Cannabis purification often involves cannabinoids, terpenes, pesticide remediation, and complex extract matrices. CPC can be relevant when a flexible preparative method is needed and packed-column approaches become too rigid or costly.

Read more about cannabinoid and THC isolation at our dedicated subpage.

Food and Nutraceuticals

Food and nutraceutical applications often involve natural colors, antioxidants, flavors, contaminants, or bioactive ingredients. CPC can support fractionation and purification when the target compound sits inside a complex natural matrix.

Cosmetics

Cosmetic ingredient development overlaps heavily with botanicals, oils, fragrances, pigments, and natural extracts. CPC can support purification, fractionation, or demonstration work for selected natural or formulation-relevant compounds.

Veterinary Pharma

Veterinary pharma faces many of the same purification questions as human pharma: actives, impurities, metabolites, intermediates, and formulation-related compounds. CPC may be useful when preparative recovery and method flexibility matter.

How LiLiChro Fits the CPC Category

LiLiChro equipment belongs to the CPC category, but the stronger educational point is that LiLiChro systems work with two liquid phases.

That matters because CPC equipment can sound like just another instrument acronym. “Two-liquid-phase purification” explains the actual separation logic.

LiLiChro’s product range is built around different development and scale needs:

• miniLiLi for laboratory method development, with 35 mL cell capacity, 1–5 mL/min flow rate, and listed stationary phase retention above 80%
• midiLiLi for lab-prep work, with 140 mL cell capacity and 4–20 mL/min flow rate
• maxiLiLi for small or pilot industrial work, with 3.5 L cell capacity and 150–500 mL/min flow rate
• prepLiLi for industrial applications, with published product information listing 100 L cell capacity, 10–30 L sample injection volume, 1–6 L/min flow rate, and 25 bar max pressure

Technical sheets also describe special Z-cell rotor design and scale-up logic from miniLiLi or midiLiLi toward maxiLiLi and prepLiLi. Contact us for a technical data sheet.

Frici and the LiLiChro team have spent years experimenting with CPC not only as a machine category, but as a practical purification mindset.

When Should You Consider CPC?

CPC is worth considering when:

• the sample is complex, crude, or natural-product-based
• packed columns suffer from adsorption or overload
• recovery matters as much as purity
• the target compound can partition between two immiscible liquids
• solvent-system screening shows useful selectivity
• preparative purification is the real goal

When the chemistry fits, CPC gives purification experts a different tool: not another solid stationary phase, but a tunable liquid-liquid environment.

Next Step

If you have a defined purification challenge, request a LiLiChro screening study. The practical first question is whether your target compound and impurities show useful behavior in a two-phase solvent system.