Protein adsorption at solid surfaces plays a key role in many natural processes and has therefore promoted a widespread interest in many research areas. Despite considerable progress in this field ...there are still widely differing and even contradictive opinions on how to explain the frequently observed phenomena such as structural rearrangements, cooperative adsorption, overshooting adsorption kinetics, or protein aggregation. In this review recent achievements and new perspectives on protein adsorption processes are comprehensively discussed. The main focus is put on commonly postulated mechanistic aspects and their translation into mathematical concepts and model descriptions. Relevant experimental and computational strategies to practically approach the field of protein adsorption mechanisms and their impact on current successes are outlined.
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► We discuss the latest findings on mechanistic details of protein adsorption. ► Important effects: cooperative adsorption, overshootings, relaxation, and aggregation. ► Experimental, mathematical, and computational concepts are reviewed.
•Sequential diethylaminoethyl dextran-grafting and diethylaminoethyl modification.•The strategy breaks through the limitation of ionic capacity of DEAE dextran-media.•The strategy significantly ...improves the adsorption performance.
Ion exchangers with high adsorption capacity, fast mass transfer, and high salt-tolerance synchronously are highly desired for high-performance protein purification. Here, we propose a sequential diethylaminoethyl dextran-grafting and diethylaminoethyl chloride modification strategy to achieve high-performance anion exchangers. The advantages of the double-modification strategy lie in: (1) the introduction of diethylaminoethyl in the second modification has no diffusion limitation due to the small molecular size, thus a high ionic capacity; (2) the grafting ligands not only provide three-dimensional adsorption space for high adsorption capacitybut alsofacilitate surface diffusion of protein by chain delivery. The maximum adsorption capacity of the obtained anion exchangers for bovine serum albumin reaches 333 mg/mL, the ratio of effective pore diffusivity (De) to free solution diffusivity (D0) reaches 0.69, and the adsorption amount reaches 97 mg/mL even in 100 mmol/L NaCl concentration,. All these results demonstrate the proposed sequential modification strategy are promising for the preparation of high-performance ion exchangers.
Biodegradable stents have paved the way to treat coronary artery disease. However, rapid reendothelialization is required to solve the problems of mismatched degradation rates, localized ...inflammation, and insufficient biocompatibility. Herein, a novel passivated protein‐adsorption coating is synthesized by coordination chelation, oxidation, cross‐linking, polymerization, and deposition of dopamine, (‐)‐epigallocatechin gallate (EGCG), and copper ions (Cu2+) using two‐electron oxidation. This coating exhibits hierarchical functionality, that is, at the macroscale, its superhydrophilicity conveys antifouling ability; whereas at the microscale, the active groups (quinone‐, amino‐, hydroxyphenyl groups and aromatic ring) facilitate protein adsorption. Antifouling ability prevents acute thrombosis and inflammation and maintains initial microenvironment stability post‐implantation. The active groups facilitate gradual endothelial cells (ECs) adhesion. Meanwhile, the decomposition of nitric oxide (NO) donors to release NO is catalyzed by Cu2+, and EGCG alleviates or prevents oxidative stress damage, inflammatory responses, thrombosis formation, and excessive smooth muscle cells proliferation in the stent microenvironment. This provides favorable conditions for the rapid and healthy growth of ECs. This study proposes a novel strategy for rapid neointima formation comprising healthy ECs on the surfaces of biodegradable stents by depositing a passivated protein‐adsorption coating (polydopamine/EGCG/Cu), opening new possibilities for the efficient treatment of coronary artery disease.
A novel passivated protein‐adsorption coating is synthesized by dopamine, EGCG and Cu2+. This coating exhibits multiscale effects: macroscopically: anti‐fouling; microscopically: protein‐promoting adhesion. The passivated protein‐adsorption platform, EGCG and Cu2+ synergistic promote timely reendothelialization by regulating the lesion microenvironment. This kind of passivated protein‐adsorption coating provide a versatile surface bioengineering strategy for a wide range of biomaterials and apparatus.
The term “zwitterionic polymers” refers to polymers that bear a pair of oppositely charged groups in their repeating units. When these oppositely charged groups are equally distributed at the ...molecular level, the molecules exhibit an overall neutral charge with a strong hydration effect via ionic solvation. The strong hydration effect constitutes the foundation of a series of exceptional properties of zwitterionic materials, including resistance to protein adsorption, lubrication at interfaces, promotion of protein stabilities, antifreezing in solutions, etc. As a result, zwitterionic materials have drawn great attention in biomedical and engineering applications in recent years. In this review, we give a comprehensive and panoramic overview of zwitterionic materials, covering the fundamentals of hydration and nonfouling behaviors, different types of zwitterionic surfaces and polymers, and their biomedical applications.
Protein adsorption, which shows wide prospects in many practical applications such as biosensors, biofuel cells, and biomaterials, has long been identified as a very complex problem in interface ...science. Here, we present a review on the multiscale modeling and simulation methods of protein adsorption on surfaces with different properties. First, various simulation algorithms (replica exchange, metadynamics, TIGER2A, and PSOVina) and protein models (colloidal, coarse-grained, and all-atom models) are introduced. Then, recent molecular simulation progresses about protein adsorption on different material surfaces (such as charged, hydrophobic, hydrophilic, and responsive surfaces) are retrospected. It has been demonstrated that the adsorption orientation of proteins on charged surfaces and hydrophobic surfaces can be controlled by the electrical dipole and the hydrophobic dipole of proteins, respectively. Superhydrophilic zwitterionic surfaces can resist protein adsorption because of the strong hydration. Under the stimuli of external conditions, the surface properties of materials can be modulated, and thus, the adsorption/desorption of proteins on responsive surfaces can be controlled. Finally, the future directions of molecular simulation study of protein adsorption are discussed.
Protein adsorption behaviors on different surfaces probed by multiscale modeling and simulations. Display omitted
•Protein adsorption shows wide prospects in many applications.•Common protein models and simulation methods adopted in molecular simulation of protein adsorption are reviewed.•Recent molecular simulation researches about protein adsorption on different surfaces are retrospected.•The future directions of protein adsorption studied by molecular simulation are suggested.
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•Application of poly(4-vinyl pyridine) layers cross-linked with transition metal complexes as active layers in biomedical sensors.•Sensitivity of the coatings to the presence of ...proteins and cells in different concentrations verified by impedance spectroscopy.•Different detection limits for different transition metals.•High selectivity of the coatings toward the defined analyte confirmed by the specific antigen–antibody immunoreaction.•Conductive response of a bilayer system that mimics Organic Field Effect Transistor.
The possibility of application of poly(4-vinyl pyridine) layers cross-linked with transition metal complexes as active layers in biomedical sensors was tested. The successful modification of the P4VP coating with CuBr2 or ZnBr2 was verified using time of flight - secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The topography and wettability of the coatings were examined by using atomic force microscopy and water contact angles measurements, respectively. Tests of biological activity of coatings indicated strong protein adsorption, good biocompatibility, and no antimicrobial activity. The potential of the coatings to be used as active layers of biosensors was verified, by systematic impedance-based measurements, which showed the sensitivity of the P4VP:CuBr2 coatings to the presence of proteins and cells in different concentrations. The high selectivity of the coatings toward the defined analyte was confirmed by the specific antigen–antibody immunoreaction, and the possibility of in situ monitoring of protein adsorption and cell adhesion also for individual cells was presented. Finally, the conductive response of a bilayer system that mimics Organic Field Effect Transistor was shown. These results point to a great potential for both coatings to serve as active layers of sensitive and highly selective biosensors.
Chromatographic media with synchronously large protein adsorption capacity and high processing flux are highly desired in protein separation; however, the creation of such materials still faces ...enormous challenges. Herein, a robust strategy to develop highly carboxylated monolithic media by combining nanofibrous aerogels' forming technique and an in situ modification approach is reported. The obtained ion‐exchange nanofibrous aerogels (IENFAs) exhibit a unique cellular structure consisting of flexible ceramic nanofibers and a functional polymer wrapping layer, endowing them with outstanding underwater superelasticity and compressive fatigue resistance (nearly no plastic deformation after 1000 compressive cycles). Benefiting from the interconnected nanofibrous cellular structure, good hydrophilicity, high carboxylation, and excellent mechanical properties, the IENFAs exhibit synchronously promoted static (2.9 × 103 mg g−1) and dynamic (1.7 × 103 mg g−1) lysozyme adsorption capacities and improved buffer flux (2.17 × 104 L m−2 h−1, gravity driven), which are superior to these reported nanofibrous materials and commercial ion‐exchange membranes. The IENFAs also possess outstanding performance stability, easy operation, and excellent regenerability. Moreover, the IENFA‐packed column could directly and continuously separate lysozyme from egg white solely driven by gravity, highlighting their excellent practical application performance. This work may provide a new avenue to design and develop next‐generation high‐performance chromatographic media for bioseparation.
Ion‐exchange nanofibrous aerogel (IENFA)–based monolithic chromatographic media with unique composite cellular structures are prepared by combining a nanofibrous aerogels forming technique with an in situ modification method. The obtained IENFAs exhibit excellent underwater superelasticity, superior compressive fatigue resistance, ultrahigh static and dynamic protein adsorption capability, extremely large processing flux, easy operation property, as well as good practical application performance.
Chiral properties of nanoscale materials are of importance as they dominate interactions with proteins in physiological environments; however, they have rarely been investigated. In this study, a ...systematic investigation is conducted for the adsorption behaviors of bovine serum albumin (BSA) onto the chiral surfaces of gold nanoparticles (AuNPs), involving multiple techniques and molecular dynamic (MD) simulation. The adsorption of BSA onto both L‐ and D‐chiral surfaces of AuNPs shows discernible differences involving thermodynamics, adsorption orientation, exposed charges, and affinity. As a powerful supplement, MD simulation provides a molecular‐level understanding of protein adsorption onto nanochiral surfaces. Salt bridge interaction is proposed as a major driving force at protein–nanochiral interface interaction. The spatial distribution features of functional groups (COO−, NH3+, and CH3) of chiral molecules on the nanosurface play a key role in the formation and location of salt bridges, which determine the BSA adsorption orientation and binding strength to chiral surfaces. Sequentially, BSA corona coated on nanochiral surfaces affects their uptake by cells. The results enhance the understanding of protein corona, which are important for biological effects of nanochirality in living organisms.
A systematic investigation for the adsorption behaviors of bovine serum albumin (BSA) onto chiral surfaces of gold nanoparticles is performed enhancing the understanding of protein corona at a molecular level. The stereoscopic configuration of chiral surfaces plays a key role in the formation of salt bridges with protein, which determines the BSA adsorption orientation and binding strength.
Recent theoretical and experimental results pertinent to protein adsorption kinetics obtained for well-defined systems using direct experimental techniques are discussed. Attention is focused on ...albumins and fibrinogen, whose structure and physicochemical characteristic are well-known. It is confirmed that the experimental data obtained by AFM imaging, QCM, OWLS, XPS and electrokinetic techniques (streaming potential) are prone to a quantitative interpretation in terms of the coarse-grained and molecular dynamics modeling. This allows to derive reliable data concerning the mass transfer rates, hydration functions, maximum coverages and adsorption/desorption kinetic constants. These results confirm that the protein adsorption mechanism is governed by electrostatic interactions among heterogeneously distributed charges. The protein substrate interactions promote the molecule transfer through the surface layer, control the free energy and in consequence the residence time of the molecule on substrate surfaces. On the other hand, the interactions among adsorbed molecules control the maximum coverage and the formation of bilayer structures. As a result of this complex electrostatics, one often observes in protein adsorption studies the formation of irreversibly bound fraction of molecules that contact the substrate and a reversibly adsorbed fraction otherwise. This leads to the appearance of anomalous isotherms, characterized by considerable adsorption for negligible bulk protein concentration, which deviate from the Langmuir model.
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