Monolithic Chromatography Techniques and Applications

Monolithic chromatography employs continuous porous materials formed in situ as stationary phases, offering high permeability, low backpressure and rapid mass transfer compared with packed beads. Two principal classes dominate the field: inorganic monoliths based on sol–gel chemistry and organic polymeric monoliths prepared via free-radical or step-growth polymerisations. Inorganic monoliths, often silica-based, provide excellent mechanical stability and chemical inertness over a broad pH range, while polymeric monoliths enable versatile surface chemistries and soft modulus for microfluidic integration. Advances in hybrid organic–silica monoliths have combined the mechanical strength of silica with the functional diversity of polymers. Control over pore architecture—from macropores that permit high flow rates to mesopores and nanopores that define separation selectivity—is achieved by tuning porogen composition, reaction kinetics and processing conditions. Applications span proteomics and metabolomics, small-molecule analysis, chiral separations, clinical diagnostics and environmental monitoring. Emerging trends include additive manufacturing of defined monolithic supports, molecular imprinting for ultrahigh selectivity, and affinity ligands grafted onto monoliths for rapid on-line sample preparation. Together, these developments are driving more efficient, high-throughput separations with reduced solvent consumption and simplified system integration for global analytical challenges.

Research from Nature Portfolio

Recent work has demonstrated a tandem monolithic affinity chromatography system for the rapid isolation of lipoproteins, notably low-density lipoprotein (LDL). A first disk functionalised with chondroitin-6-sulfate removes non-target lipoprotein particles, while a second disk bearing anti-apoB-100 antibody captures LDL with high specificity. This two-stage protocol reduces isolation time to under thirty minutes and delivers purity comparable to ultracentrifugation, offering a streamlined platform for clinical assays and proteomic workflows with minimal equipment requirements.

Research from all publishers

Two recent studies have advanced the fabrication and functional performance of monolithic chromatographic supports. A novel sol–gel strategy utilising sub- and supercritical water has been shown to induce controlled dissolution and coalescence of discrete silica microspheres into homogeneous three-dimensional monoliths. The resulting hybrid capillary columns, modified with C18 chemistry, exhibit adjustable permeability and superior chromatographic efficiency relative to packed beds, especially at elevated pressures and high flow rates. In an organic polymer approach, porous monoliths synthesised through aza- and thio-Michael addition reactions achieve fine control over nanostructural networks by varying monomer types, catalyst levels and reaction conditions. This methodology yields co-continuous or globular pore morphologies with tunable mechanical properties and flow resistance, highlighting the potential of Michael addition chemistry to tailor monoliths for demanding separation tasks.

Monolithic Chromatography Techniques and Applications publication trend

The graph below shows the total number of articles in monolithic chromatography techniques and applications across all publications each year (not limited to Nature Index journals).

Technical terms

Monolith: A continuous porous stationary phase formed in situ within a column or capillary, providing interconnected channels for chromatography.

Porogen: A solvent or additive introduced during monolith synthesis to induce phase separation and generate pores of defined size and distribution.

Stationary phase: The immobilised material within a chromatography column where analytes are retained and separated according to their interactions.

Affinity ligand: A molecule covalently attached to the stationary phase that selectively binds target analytes through specific biological or chemical recognition.

Sol–gel process: A route to prepare inorganic monoliths via hydrolysis and polycondensation of metal alkoxide precursors, yielding rigid porous networks.

References

1. Forming Homogeneous Three-Dimensional Structures from Discrete Silica Microspheres Using Sub/Supercritical Water. ACS Applied Materials & Interfaces (2024).
2. Synthesis and properties of porous polymers synthesized by Michael addition reactions of multi-functional acrylate, diamine, and dithiol compounds. RSC Advances (2020).
3. Rapid affinity chromatographic isolation method for LDL in human plasma by immobilized chondroitin-6-sulfate and anti-apoB-100 antibody monolithic disks in tandem. Scientific Reports (2019).