Biomacromolecules:analysis and purification

SummaryTen principal conclusions

1Seven modalities and their physicochemical profiles

"Biomacromolecule" is not a single category in a downstream process context. The modalities differ considerably in molecular weight, hydrodynamic radius, isoelectric point, surface hydrophobicity and conformational stability, and those differences directly determine the chromatographic modes available, the pore size range and the operating conditions that can be tolerated. The table summarizes seven modalities against the dimensions that matter downstream, and each row can be reached from the category buttons below.

How this relates to the other solution pages on this site: modified silica selection and process parameters for class G peptides are on the peptide API purification page, and oligonucleotide drugs page; this page focuses on soft gel and polymer media under aqueous conditions.

2Six structural differences from small-molecule purification

Applying small-molecule preparative chromatography experience directly to biomacromolecules usually leads to errors in capacity, flow rate and recovery. The differences can be grouped into six points.

The pressure ranges in the table are common engineering values; follow each medium's official specification. The official values collected on this page are in Chapters 12–14.

3Starting material and pretreatment routes

The starting point for a downstream process is set by the upstream expression system. Different starting points call for different pretreatment before the first chromatographic step.

Fig. 3-1Six classes of starting material and their pretreatment routes

4Systematic mapping of the impurity profile

The impurity control target determines how many process steps are needed. Grouping impurities by origin and by removal method helps establish which step needs which orthogonal mode.

Fig. 4-1Impurity profile → removal method → corresponding media

5The three-stage process framework and platform processes

Downstream processes generally follow a three-stage division into capture, intermediate purification and polishing (CIPP). The three stages have different optimization objectives, so media selection emphasizes different things at each.

Fig. 5-1The CIPP three-stage framework and what media selection emphasizes at each stage

A fairly mature platform process has emerged in antibodies: protein A affinity capture → low pH viral inactivation → anion exchange flow-through → cation exchange or mixed mode polishing → nanofiltration → ultrafiltration/diafiltration. The value of a platform lies in a shorter development cycle and reusable regulatory documentation; its limitation is that molecules with an atypical pI, atypical glycoform or a tendency to aggregate still need case-by-case adjustment in the polishing stage.

6Mechanisms of the seven chromatographic modes and their orthogonality

The seven modes differ not in efficiency but in which molecular property each of them "sees". The figure below places the adsorption mechanisms of all seven on one diagram, and the table that follows gives the operating conditions and limitations of each.

Fig. 6-1Mechanisms of the seven chromatographic modes: each recognizes a different molecular property

6.1 How to judge orthogonality

Whether two steps are orthogonal depends on whether the molecular properties they rely on are independent. Ion exchange and hydrophobic interaction depend on net charge and surface hydrophobicity respectively, which correlate weakly, so an IEX→HIC combination adds effectively to impurity clearance in most systems. Conversely, two cation exchange steps differing only in ligand (CM and S) are orthogonal to a limited degree, contributing mainly through capacity and fine adjustment of selectivity rather than through complementary mechanisms.

Fig. 6-2Mode × recognized property orthogonality matrix

6.2 The value of flow-through mode

Where the target is unretained under particular conditions while impurities are retained, a flow-through mode can be used. Throughput is higher than in bind-elute mode, and there is no dilution from an elution step. AEX flow-through is commonly used in antibody processes to remove DNA, endotoxin and acidic HCP; Cellufine Phenyl EX also supports removal of mAb aggregates in flow-through at a low conductivity of about 6 mS/cm, which lowers the risk of equipment corrosion and buffer precipitation associated with high salt. Manufacturer data

Fig. 6-3Bind-elute versus flow-through: whether the target is retained determines throughput and dilution

7Non-chromatographic unit operations

8Comparison of the five families of base matrix

The base matrix determines the medium's rigidity, hydrophilicity, chemical tolerance and achievable pore structure; ligand chemistry works only within the framework the base matrix allows.

Fig. 8-1Where the five families of base matrix sit on the rigidity–hydrophilicity plane

Fig. 8-2The dextran grafted layer: raising dynamic capacity without changing the rigidity of the base matrix

9Engineering parameters: capacity, flow rate, particle size and pore size

9.1 Dynamic binding capacity and residence time

Dynamic binding capacity (DBC) is the mass of target bound per unit volume of medium at the point where the effluent concentration reaches a given fraction (usually 10%) of the feed, at a given flow rate. DBC rises as residence time lengthens, so media must be compared at the same residence time. The published examples collected on this page are:

• Cellufine SPA-HC: pAb DBC > 70 mg/mL (6 min residence); mAb DBC > 65 mg/mL (4 min residence).
• Cellufine MAX GS: IgG 10% DBC ≥ 70 mg/mL (4 min residence).
• Cellufine MAX IEX series: the manufacturer states that dynamic capacity does not change with flow rate, and that the linear velocity can be raised to 500 cm/h.

Fig. 9-1Breakthrough curves and the DBC–residence time relationship

9.2 Particle size, bed height and resolution

Within one base matrix system, a smaller particle raises efficiency but also raises pressure drop. The gel media line covers the different process stages by banding particle size: Microse 6 Fast Flow at 90 μm and ≤ 600 cm/h for capture and intermediate purification; Microse 6 HP at 34 μm and ≤ 150 cm/h for polishing; Microse 6 Big Beads at 100–300 μm and ≤ 1800 cm/h for rapid processing of viscous or large-volume feeds.

9.3 Pore size and exclusion limit

Gel filtration media are characterized by separation range; adsorptive media by the exclusion limit, which sets the upper size that can enter the pores. The exclusion limit of the Cellufine ion exchange base grades runs from > 30 kDa for A-200 to > 1000 kDa for A-800, with corresponding capacity for targets of different molecular weight: A-800 gives a BSA dynamic capacity of 84 mg/mL against 46 mg/mL for A-200, but its ion exchange capacity (0.05–0.08 meq/mL) is lower than that of A-200 (0.13–0.18 meq/mL). This shows that capacity is not determined by ligand density alone; accessible surface area is equally decisive.

Fig. 9-2Two uses of pore size versus molecular size: get into the pore for capacity, or stay out of it and use exclusion

10Cleaning, regeneration and media lifetime

The unit cost of an industrial chromatography medium is amortized over the number of cycles, so tolerance of in-line cleaning (CIP) directly affects process economics. Sodium hydroxide is the usual CIP agent, removing protein residues, inactivating micro-organisms and degrading endotoxin at once.

Fig. 10-1CIP tolerance of the three product lines and the stability data published for each

Storage: both PolymerOne reversed-phase and ion exchange media are stated to be stored in 20% ethanol at room temperature. "——" in the table indicates that the manufacturer does not publish the corresponding data.

11Quality and regulatory perspective

12JNC Cellufine crosslinked cellulose media

Cellufine is the cellulose-based chromatography media range of JNC Corporation, Japan, built on crosslinked cellulose microspheres. The shared characteristics are: spherical crosslinked cellulose microspheres combining hydrophilicity with mechanical strength; low non-specific adsorption; ion exchange base grades running to 1200 cm/h at a backpressure < 0.3 MPa and tolerating in-line cleaning with 0.5 M NaOH; and the MAX series using a bridging technology to optimize surface modification and pore uniformity. The whole range is stated to be certified to ISO 9001. Microwants is the distributor for mainland China. Specifications and part numbers are at Products · JNC Cellufine cellulose media。

12.1 Ion exchange: base grades (A / C / Q / S series)

Shared characteristics: a bridged spherical cellulose particle matrix; linear velocity to 1200 cm/h at a backpressure < 0.3 MPa; tolerates in-line cleaning with 0.5 M NaOH. BSA and lysozyme are the proteins used to determine dynamic binding capacity.

12.2 Ion exchange: MAX series (dextran-coated)

The MAX series grafts ion exchange ligands onto a dextran polymer layer on the cellulose bead using a bridging technology, so the target protein diffuses quickly into the micropores. The manufacturer states that the dynamic capacity of every MAX IEX grade is independent of flow rate, that the linear velocity can be raised to 500 cm/h, and that the operating pressure is < 0.3 MPa throughout.

The manufacturer states that MAX Q-hv and MAX Butyl HS are designed for polysaccharide vaccine purification (pneumococcal capsular polysaccharide, for example); the quantitative parameters for both are shown as "——" on the product page.

12.3 Dedicated aggregate removal: Cellufine MAX GS

MAX GS is a strong cation medium designed to remove aggregates from the mAb pool recovered after protein A capture. A polymer carrying ion exchange ligands is grafted onto the particle surface, using molecular structure to distinguish mAb monomer from aggregates selectively.

12.4 Protein A affinity: Cellufine SPA-HC

12.5 Affinity chromatography: Sulfate, MAX DexS, Phosphate and Formyl

Sulfate is an affinity medium with a heparin-mimetic ligand, used to separate and purify vaccine viruses (influenza, rabies, Japanese encephalitis and others), usually binding at low salt and eluting at high salt, and stated to work irrespective of whether the virus is grown in eggs or in cell culture. The MAX DexS series uses dextran sulfate, similar to animal-derived heparin, as the ligand; the two differ in the length of the dextran sulfate polymer.

Because its ligand carries a negative charge, Cellufine Phosphate also functions as a cation exchanger and can be used as one; in mRNA in vitro transcription (IVT) processes it is used to purify T7 RNA polymerase, with enzyme activity recovery in the eluted fractions recorded at about 70%. A high-capacity version, Cellufine Phosphate HC, is also available. The aldehyde group of Formyl reacts with a ligand's primary amine to form a Schiff base, converted to a covalent bond by mild reductive amination. Manufacturer data

12.6 Endotoxin removal: Cellufine ET Clean L / S

Poly-ε-lysine is the ligand, binding endotoxin in the sample selectively. The ligand is a polymer of 25–35 lysine residues produced by Streptomyces albulus . ET Clean L has a large exclusion limit and suits higher molecular weight proteins; ET Clean S has a small exclusion limit and suits smaller molecules. The manufacturer records a ligand concentration > 1 μmol/mL and an exclusion limit of 2×10⁶ for ET Clean L, with typical performance of residual LPS < 10 pg/mL and protein recovery of 97–98%.

12.7 Hydrophobic interaction: Phenyl EX and the MAX HIC series

Fig. 12-1The HIC ligand density trade-off: binding capacity and recovery move in opposite directions

Resolving power runs MAX Phenyl > MAX Phenyl LS > MAX Butyl. Polyclonal IgG 10% DBC: MAX Butyl 17, MAX Phenyl 19, MAX Phenyl LS 30 mg/mL. Phenyl EX can be used for two-step antibody purification in flow-through mode, removing mAb aggregates at a low conductivity of about 6 mS/cm; adsorption performance was essentially unchanged after 60 cycles of CIP with 0.5 M NaOH + 30% isopropanol.

12.8 Mixed mode and gel filtration

The Cellufine system also offers the Super Edge empty prepacked column system, comprising a screw packing rod, a packing reservoir, an empty column kit and quick connectors, for self-packing mini-columns from bulk media for small-scale screening. Packing operations and equipment support are at column packing services and Packing stations。

13Gel media: Mixdex / Microse / Micdex / Mixrose

These gel chromatography media are built on crosslinked agarose (Microse), crosslinked dextran (Micdex) and near-rigid crosslinked agarose (Mixrose), covering gel filtration, ion exchange and mixed mode. The whole range has a hydrophilic base matrix with low non-specific adsorption, tolerates in-line cleaning with NaOH and HCl, and is available in PrePack prepacked columns. Part numbers follow the 2022 edition of the agarose and dextran gel handbook; specifications are at Products · gel media。

13.1 Gel filtration media

Mixdex is a composite of dextran and highly crosslinked agarose, characterized by high flow rate and pressure rating, relatively high resolution and low non-specific adsorption. The start of the separation range for Mixdex 200 pg was truncated in the page extraction; follow the current handbook.To be verified

Microse Fast Flow is stated to be stable in ordinary aqueous solutions and to tolerate 8 M urea, 6 M guanidine hydrochloride, 70% ethanol and 1–2 M sodium hydroxide; the listed applications are separation of large biomolecules such as viruses and plasmids. The conventional grades have lower resolution and suit biomolecules well separated in molecular weight.

Micdex G-50 Medium has a part number listed on the manufacturer's site, with a particle size range adjacent to G-50 Fine; follow the current handbook for exact figures. The place of LH-20 in natural product separation is covered in Chapter 13 of the natural product purification page。

13.2 Ion exchange media

The Mixrose series is based on near-rigid crosslinked agarose microspheres, with near-rigid physical characteristics and a narrow bead size distribution; IEX Microse is agarose-based, in four sub-series — Fast Flow, High Performance, Big Beads and XL; IEX Micdex is a crosslinked dextran ion exchanger. The functional groups cover strong anion (Q), strong cation (SP), weak anion (DEAE) and weak cation (CM).

The "Mixrose HR characteristics" section lists a separate set of figures: Q HR strong anion, mean particle size 40 μm, capacity > 55 mg BSA/mL; SP HR strong cation, 40 μm, > 70 mg lysozyme/mL; DEAE HR weak anion, 40 μm, > 60 mg BSA/mL; CM HR weak cation, 40 μm, > 60 mg lysozyme/mL. The particle size given there for CM HR differs from the 90 μm in the table above; check against the current handbook when selecting.

The Q Micdex series also includes grades such as A-50; some rows in the manufacturer's table were truncated, so request the full catalogue when selecting.To be verified

13.3 Mixed mode media and prepacked columns

PrePack prepacked columns: gel filtration types are available as 16/600 and 26/600 (column volumes 120 / 320 mL, rated 0.3 MPa); ion exchange types as 7/25, 16/25, 8/100 and 16/100 (rated 0.3 MPa, maximum flow rate 4–20 mL/min), covering Microse FF / HP / XL and the Mixrose functional groups; Micdex desalting prepacked columns (16/25, 8/100, 16/100, column volumes 5–20 mL) are also available. The manufacturer also publishes process examples: the process flow and chromatograms for purifying human rabies vaccine on Microse 4 Fast Flow, and the process flow for purifying supercoiled plasmid pDNA on Microse 6 Fast Flow.

14PolymerOne polymer media

The PolymerOne® polymer microsphere range is built on highly crosslinked polystyrene/divinylbenzene (PS/DVB) and polymethacrylate (PMMA), with uniform microspheres from 50 nm to 1000 μm produced at scale, covering reversed-phase and ion exchange chromatography. Microwants is an authorized distributor and supports customization of crosslinking, particle size, pore size and functional group. Specifications are at Products · PolymerOne polymers。

14.1 Polystyrene microspheres (PS microspheres)

Uniform PS microspheres from 50 nm to 1000 μm can be produced at scale, with surface modification to give carboxyl, amino, epoxy and other functionalized microspheres, and products can be made to order at different degrees of crosslinking and with different functional groups. The manufacturer lists more than ten particle size grades from 10PS to 1000PS (10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100…300, 400, 500, 600, 700, 800, 900, 1000 μm), each available with four surfaces: plain, carboxyl, amino and epoxy. The stated characteristics are regular sphericity, CV < 3%, high chemical stability and good dispersibility.

14.2 Polymer reversed-phase media (PS/DVB · PSM · PMM)

Chemical stability is stated for pure water, isopropanol, ethanol, acetonitrile, 1 M HCl, 1 M NaOH, methanol and most other solvents. The recommended cleaning and regeneration is: flush with 0.1–0.5 M NaOH in 60% methanol, then 0.1–0.5 M HCl in 60% methanol, then equilibrate with mobile phase. Surface area, crosslinking and maximum pressure are not listed individually for the other grades.

14.3 Polymer ion exchange media

Built on highly crosslinked uniform polyacrylate (PMMA) or PS/DVB microspheres, and stated to be highly rigid, acid- and alkali-tolerant, with low backpressure, high resolution and high operating flow rates. The PM series forms a hydrophilic coating on the polyacrylate microsphere before introducing the ion exchange group, to suppress non-specific adsorption and reduce steric hindrance; the M series bonds the ion exchange group directly to the polyacrylate microsphere surface, giving both hydrophobic and ion exchange character; the PS/DVB series bonds the ion exchange group directly to a PS/DVB microsphere.

Published stability data: dynamic binding capacity for insulin was essentially unchanged after 30 days' immersion in 1.0 mol/L NaOH; and compared with conventional agarose-based ion exchangers, the change in column volume at high flow rate and raised pressure is smaller.Manufacturer data

15Comparison of the three product lines

Fig. 15-1Particle size versus stated maximum linear velocity: the product lines band particle size to match the three process stages

The figure notes why PolymerOne is not included: it is specified by pressure rating (of the order of 100 bar) rather than by linear velocity, and its range lies on the high-pressure side outside the plotted region.

16Modality × stage × media master matrix

The table below cross-maps the seven modalities of Chapter 1, the three process stages of Chapter 5 and the product grades of Chapters 12–14. The entries are suggestions derived from the officially stated applications and parameters; actual selection must be confirmed by bench screening. The rows correspond by number to the modality table in Chapter 1.

17Eight representative process routes

The routes below are organized around the officially stated applications, to show how the media connect within a process chain. The buffer system, gradient and loading for each step must be established for the specific molecule at bench scale. The first route (the mAb platform process) is used as an example to draw out how the chromatographic and non-chromatographic steps connect.

Fig. 17-1The full mAb platform process chain: how chromatographic and non-chromatographic steps connect

The routes above are example configurations organized from the officially stated applications (inferred on this page) and do not constitute a process recommendation for any particular product. An actual process requires process validation and viral clearance validation.

18The selection decision path

Fig. 18-1A three-step path for selecting biomacromolecule chromatography media

18.1 Rules for trading capacity against resolution

• The capture stage aims at throughput per unit time, so high flow rate and high DBC grades come first: the FF, XL and BB sub-series in the gel media system, and the MAX series in the Cellufine system.
• The polishing stage aims at resolution, so 34–40 μm HP and HR grades are used, or grades designed for a particular impurity (MAX GS for aggregate removal, Mixrose MMC HR for isomer separation).
• Where one step needs both capacity and resolution, this is usually achieved by lengthening residence time (lowering the flow rate) rather than moving to a smaller particle, because the resulting rise in pressure drop is constrained in soft gel systems by the pressure rating (usually 0.3 MPa).

18.2 Items to confirm at bench scale

19One-page quick reference

20Data basis, information gaps and scope

20.1 Data basis

• The product parameters in Chapters 12–14 are taken from the "JNC Cellufine cellulose media", "gel media" and "PolymerOne polymers" sections of the Products area of this site, retrieved on 5 August 2026.
• The protein used to determine dynamic binding capacity is not consistent between product lines: Cellufine and the gel media mostly use BSA (anion grades) and lysozyme (cation grades), with γ-globulin or IgG also given for some grades. Bear this in mind when comparing capacity figures across product lines.
• "Separation range" for gel filtration media and "exclusion limit" for adsorptive media are two different measures and cannot be compared directly.
• For flow rate, Cellufine and the gel media are specified by linear velocity (cm/h) and PolymerOne by pressure rating (bar); the two must be converted using the column geometry before comparison.

20.2 Information not published by the manufacturers

20.3 Notes on data consistency

20.4 Scope

This page is a technical review and a selection reference. The process routes given are example configurations organized from the officially stated applications and do not replace the experimental data required for process development, process validation and regulatory filing. Process design for a specific product must be established separately from the measured physicochemical properties, impurity profile and regulatory requirements of the target molecule. The suitability, lifetime and scale-up behaviour of a medium should be confirmed with bench and pilot data.

AppendixChinese–English glossary