Affinity chromatography is a separation technique that has become increasingly important in work with biological samples and pharmaceutical agents. This method is based on the use of a biologically ...related agent as a stationary phase to selectively retain analytes or to study biological interactions. This review discusses the basic principles behind affinity chromatography and examines recent developments that have occurred in the use of this method for biomedical and pharmaceutical analysis. Techniques based on traditional affinity supports are discussed, but an emphasis is placed on methods in which affinity columns are used as part of HPLC systems or in combination with other analytical methods. General formats for affinity chromatography that are considered include step elution schemes, weak affinity chromatography, affinity extraction and affinity depletion. Specific separation techniques that are examined include lectin affinity chromatography, boronate affinity chromatography, immunoaffinity chromatography, and immobilized metal ion affinity chromatography. Approaches for the study of biological interactions by affinity chromatography are also presented, such as the measurement of equilibrium constants, rate constants, or competition and displacement effects. In addition, related developments in the use of immobilized enzyme reactors, molecularly imprinted polymers, dye ligands and aptamers are briefly considered.
Isolation or enrichment of biological molecules from complex biological samples is mostly a prerequisite in proteomics, genomics, and glycomics. Different techniques have been used to advance the ...efficiency of the purification of biological molecules. Bioaffinity chromatography is one of the most powerful technique that plays an important role in the isolation of target biological molecules by the specific interactions with ligands that are immobilized on different support materials. This review examines the recent developments in bioaffinity chromatography particularly over the past 5 years in the literature. Also properties of supports, immobilization techniques, types of binding agents, and methods used in bioaffinity chromatography applications are summarized.
Affinity chromatography is one of the most selective and versatile forms of liquid chromatography for the separation or analysis of chemicals in complex mixtures. This method makes use of a ...biologically related agent as the stationary phase, which provides an affinity column with the ability to bind selectively and reversibly to a given target in a sample. This review examines the early work in this method and various developments that have lead to the current status of this technique. The general principles of affinity chromatography are briefly described as part of this discussion. Past and recent efforts in the generation of new binding agents, supports, and immobilization methods for this method are considered. Various applications of affinity chromatography are also summarized, as well as the influence this field has played in the creation of other affinity-based separation or analysis methods.
•We summarize strategies for phosphopeptide enrichment.•We highlight and discuss recent advances in phosphopeptide enrichment such as the novel techniques developed.•Enrichment strategies for ...multi-phosphopeptides and endogenous phosphopeptides are summarized and discussed.
Phosphoproteomics has become one of the most active research areas in proteomics studies. Phosphopeptide enrichment is a critical and indispensable step in phosphoproteomics. To date, a variety of strategies and techniques have been developed for the selective enrichment of phosphopeptides. With the progress of science and technology, novel methods are being continually developed to enhance the specificity and selectivity of the enrichment strategies. In this review, we summarize and discuss recent advances of strategies for phosphopeptide enrichment and highlight novel techniques developed in this research field. In addition, strategies for specific phosphopeptide enrichment including multi-phosphopeptides and endogenous phosphopeptides are also summarized and discussed.
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•A magnetic material mMOF-FBP-Ti4+ were developed for phosphopeptides enrichment.•mMOF-FBP-Ti4+ captured phosphopeptides under interactions of MOAC, IMAC and HILIC.•mMOF-FBP-Ti4+ ...showed low LOD, high selectivity, great reusability and recovery.•mMOF-FBP-Ti4+ could be used to capture phosphopeptides from biological samples.
Highly selective enrichment of low abundance phosphopeptides from intricate biological samples before mass spectrometry detection is a vital prerequisite for in-depth phosphoproteomics. Herein, a magnetic material mMOF-FBP-Ti4+ is fabricated by grafting UiO-66-NH2 metal–organic framework (Zr-MOF) onto the surface of Fe3O4, and subsequently immobilizing Ti(IV) on the mMOF with fructose 1,6-bisphosphate as chelating ligands. The obtained mMOF-FBP-Ti4+ showed large specific surface area (202.4 m2 g−1) and superparamagnetism (47.5 emu/g). The intrinsic Zr − O clusters of mMOF and the immobilized Ti(IV) ions on the surface of mMOF could interact with phosphopeptides as metal oxide affinity chromatography (MOAC) and immobilized metal affinity chromatography (IMAC), respectively. The introduction of fructose 1,6-bisphosphate also improved the hydrophilicity of the material, which enhanced the hydrophilic chromatography interaction (HILIC) between mMOF-FBP-Ti4+ and phosphopeptides. The above strong affinities provided low limit of detection (0.2 fmol μL−1), high selectivity (α-/β-casein/BSA tryptic digests with a mass ratio of 1:1:500), great reusability (three times circles) and good postenrichment recovery (90.2 %) towards phosphopeptides. Furthermore, the mMOF-FBP-Ti4+ was successfully applied to capture phosphopeptides from non-fat milk tryptic digest and human saliva, indicating its great potential for highly efficient enrichment of low-abundance phosphopeptides in complex biological samples.
•Autocatalytic and oriented coupling of nanobody ligand through Spy-based strategy.•This strategy significantly improves ligand coupling efficiency and binding capacity.•Nanobody ligand can be ...immobilized without any pre-purification steps.•The resin is effective and stable throughout multiple cycles.•This strategy can serve as a potential platform for developing affinity resin.
The use of nanobodies (Nbs) in affinity chromatography for biomacromolecule purification is gaining popularity. However, high-performance Nb-based affinity resins are not readily available, mainly due to the lack of suitable immobilization methods. In this study, we explored an autocatalytic coupling strategy based on the SpyCatcher/SpyTag chemistry to achieve oriented immobilization of Nb ligands. To facilitate this approach, a variant cSpyCatcher003 (cSC003) was coupled onto agarose microspheres, providing a specific attachment site for SpyTagged nanobody ligands. The cSC003 easily purified from Escherichia coli through a two-step procedure, exhibits exceptional alkali resistance and structural recovery capability, highlighting its robustness as a linker in the coupling strategy. To validate the effectiveness of cSC003-derivatized support, we employed VHSA, a nanobody against human serum albumin (HSA), as the model ligand. Notably, the immobilization of SpyTagged VHSA onto the cSC003-derivatized support was achieved with a coupling efficiency of 90 %, significantly higher than that of traditional thiol-based coupling method. This improvement directly correlated to the preservation of the native conformation of nanobodies during the coupling process. In addition, the Spy-immobilized resin demonstrated better performance in the binding capacity, with a 3-fold improvement in capture efficiency, underscoring the advantages of the Spy immobilization strategy for oriented immobilization of VHSA ligands. Moreover, online purification and immobilization of SpyTagged VHSA from crude bacterial lysate was achieved using the cSC003-derivatized support. The resulting resin exhibited high binding specificity towards HSA, yielding a purity above 95 % directly from human serum, and maintained good stability throughout multiple purification cycles. These findings highlight the potential of the Spy immobilization strategy for developing Nb-based affinity chromatographic materials, with significant implications for biopharmaceutical downstream processes.
The discovery of enzyme inhibitors from natural products is a crucial aspect in the development of therapeutic drugs. However, the complexity of natural products presents a challenge in developing ...simple and efficient methods for inhibitor screening. Herein, we have developed an integrated analytical model for screening xanthine oxidase (XOD) inhibitors that combines simplicity, accuracy, and efficiency. This model utilizes a colorimetric sensor and affinity chromatography technology with immobilized XOD. The colorimetric sensor procedure can quickly identify whether there are active components in complex samples. Subsequently, the active components in the samples identified by the colorimetric sensor procedure were further captured, separated, and identified through affinity chromatography. The integrated analytical model can significantly enhance the efficiency and accuracy of inhibitor screening. The proposed method was applied to screen for an activity inhibitor of XOD in five natural medicines. As a result, a potential active ingredient for XOD, polydatin, was successfully identified from Polygoni Cuspidati Rhizoma et Radix. This work is anticipated to offer new insights for the screening of enzyme inhibitors from natural medicines.
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•Heptapeptide of β2-AR recognizes ephedrine and pseudoephedrine epimers in solution.•Immobilized peptide separates the epimers in herbal extract and blood samples.•An enhanced hydrogen bonding was ...found in heptapeptide-pseudoephedrine complex.
Epimer separation is crucial in the field of analytical chemistry, separation science, and the pharmaceutical industry. No reported methods could separate simultaneously epimers or even isomers and remove other unwanted, co-existing, interfering substances from complex systems like herbal extracts. Herein, we prepared a heptapeptide-modified stationary phase for the separation of 1R,2S-(-)-ephedrine (-)-Ephe and 1S,2S-(+)-pseudoephedrine (+)-Pse epimers from Ephedra sinica Stapf extract and blood samples. The heptapeptide stationary phase was comprehensively characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The separation efficiency of the heptapeptide column was compared with an affinity column packed with full-length β2-AR functionalized silica gel (β2-AR column). The binding affinity of the heptapeptide with (+)-Pse was 3-fold greater than that with (-)-Ephe. Their binding mechanisms were extensively characterized by chromatographic analysis, ultraviolet spectra, circular dichroism analysis, isothermal titration calorimetry, and molecule docking. An enhanced hydrogen bonding was clearly observed in the heptapeptide-(+)-Pse complex. Such results demonstrated that the heptapeptide can recognize (+)-Pse and (-)-Ephe epimers in a complex system. This work, we believe, was the first report to simultaneously separate epimers and remove non-specific interfering substances from complex samples. The method was potentially applicable to more challenging sample separation, such as chiral separation from complex systems.
Affinity monolith chromatography (AMC) is a type of liquid chromatography that uses a monolithic support and a biologically related binding agent as a stationary phase. AMC is a powerful method for ...the selective separation, analysis, or study of specific target compounds in a sample. This review discusses the basic principles of AMC and recent developments and applications of this method, with particular emphasis being given to work that has appeared in the last 5 years. Various materials that have been used to prepare columns for AMC are examined, including organic monoliths, silica monoliths, agarose monoliths, and cryogels. These supports have been used in AMC for formats that have ranged from traditional columns to disks, microcolumns, and capillaries. Many binding agents have also been employed in AMC, such as antibodies, enzymes, proteins, lectins, immobilized metal ions, and dyes. Some applications that have been reported with these binding agents in AMC are bioaffinity chromatography, immunoaffinity chromatography or immunoextraction, immobilized-metal-ion affinity chromatography, dye–ligand affinity chromatography, chiral separations, and biointeraction studies. Examples are presented from fields that include analytical chemistry, pharmaceutical analysis, clinical testing, and biotechnology. Current trends and possible directions in AMC are also discussed.