Simplification of affinity macroporous monolith microfluidic column synthesis and its ability for protein separation

Titanium particles incorporated polymer monolith microcolumn for phosphoprotein enrichment from biological samples

In proteomic studies, selective enrichment of target phosphoproteins from biological samples is of importance. Of various enrichment methods, affinity chromatography is widely preferred method. Development of micro-affinity columns with simple strategies are in constant demand. Here in this report, for the first time, we have embedded TiO₂ particles within the monolith structure in a single step. Fourier transform infrared spectroscopy and scanning electron microscope analysis has confirmed the successful incorporation of TiO₂ particles within the polymer monolith. Incorporation of 3-(trimethoxy silyl) propyl methacrylate within the poly(hydroxyethyl methacrylate) based monolith composition has enhanced its rigidity and one fold phosphoprotein (α-casein) adsorption capacity. Presence of only 66.6 µg of TiO₂ particles within the monolith has displayed a four-fold higher affinity to α-casein over the non-phosphoprotein i.e. bovine serum albumin. Under optimized conditions (TiO₂ particle and acrylate silane), the affinity monolith has a maximum adsorption capacity of ∼ 72 mg per gram monolith. Translation of TiO₂ particles-monolith into a microcolumn of 3 cm long and 19 µL volume was successful. α-casein was selectively separated from an artificial protein mixture of α-casein and BSA, α-casein spiked human plasma, and cow milk within 7 min.

Preparation of Affinity Chromatography Monolith in Miniaturized Format and Application for Protein Separation

Affinity chromatography is one of the versatile technique to selectively separate target biomolecules from complex biological sources (plasma, saliva, urine, etc.). Conventional chromatography resins possess technical limitations at mini-analytical scale, which was overcome with the use of alternative material known as monoliths. This chapter discusses on the how to modify the fused silica capillary inner surface, prepare polymer monoliths within the capillary confinements, chelation of metal-ions on monoliths and protein separation from diluted human plasma using metal-ion monolith microcolumn.

Affinity monolith chromatography: A review of general principles and recent developments

Affinity monolith chromatography (AMC) is a liquid chromatographic technique that utilizes a monolithic support with a biological ligand or related binding agent to isolate, enrich, or detect a target analyte in a complex matrix. The target-specific interaction exhibited by the binding agents makes AMC attractive for the separation or detection of a wide range of compounds. This article will review the basic principles of AMC and recent developments in this field. The supports used in AMC will be discussed, including organic, inorganic, hybrid, carbohydrate, and cryogel monoliths. Schemes for attaching binding agents to these monoliths will be examined as well, such as covalent immobilization, biospecific adsorption, entrapment, molecular imprinting, and coordination methods. An overview will then be given of binding agents that have recently been used in AMC, along with their applications. These applications will include bioaffinity chromatography, immunoaffinity chromatography, immobilized metal-ion affinity chromatography, and dye-ligand or biomimetic affinity chromatography. The use of AMC in chiral separations and biointeraction studies will also be discussed.

Recent advances in protein chromatography with polymer-grafted media

The strategy of using polymer-grafted media is effective to create protein chromatography of high capacity and uptake rate, giving rise to an excellent performance in high-throughput protein separation due to its high dynamic binding capacity. Taking the scientific development and technological innovation of protein chromatography as the objective, this review is devoted to an overview of polymer-grafted media reported in the last five years, including their fabrication routes, protein adsorption and chromatography, mechanisms behind the adsorption behaviors, limitations of polymer-grafted media and chromatographic operation strategies. Particular emphasis is placed on the elaboration and discussion on the behaviors of ion-exchange chromatography (IEC) with polymer-grafted media because IEC is the most suitable chromatographic mode for this kind of media. Recent advances in both the theoretical and experimental investigations on polymer-grafted media are discussed by focusing on their implications to the rational design of novel chromatographic media and mobile phase conditions for the development of high-performance protein chromatography. It is concluded that polymer-grafted media are suitable for development of IEC and mixed-mode chromatography with charged and low hydrophobic ligands, but not for hydrophobic interaction chromatography with high hydrophobic ligands and affinity chromatography with ligands that have single binding site on the protein.