Bovine Serum Research Articles

Multifunctional Self-Assembled Bio-Interfacial Layers for High-Performance Zinc Metal Anodes.

Rechargeable aqueous zinc-ion (Zn-ion) batteries are widely regarded as important candidates for next-generation energy storage systems for low-cost renewable energy storage. However, the development of Zn-ion batteries is currently facing significant challenges due to uncontrollable Zn dendrite growth and severe parasitic reactions on Zn metal anodes. Herein, we report an effective strategy to improve the performance of aqueous Zn-ion batteries by leveraging the self-assembly of bovine serum albumin (BSA) into a bilayer configuration on Zn metal anodes. BSA's hydrophilic and hydrophobic fragments form unique and intelligent ion channels, which regulate the migration of Zn ions and facilitate their desolvation process, significantly diminishing parasitic reactions on Zn anodes and leading to a uniform Zn deposition along the Zn (002) plane. Notably, the Zn||Zn symmetric cell with BSA as the electrolyte additive demonstrated a stable cycling performance for up to 2400 hours at a high current density of 10 mA cm-2. This work demonstrates the pivotal role of self-assembled protein bilayer structures in improving the durability of Zn anodes in aqueous Zn-ion batteries.

Hydrogen-Bonded Organic Framework Enhanced Antifouling Property for Efficient In Situ Electrochemical Assay of Cerebral Ascorbic Acid.

Accurate determination of cerebral ascorbic acid (AA) is crucial for understanding ischemic stroke (IS) related pathological events. Carbon fiber microelectrodes (CFEs) have proven to be robust tools with high sensitivity toward AA, however, they face ongoing challenges for in situ measurement due to the non-specific adsorption of proteins in brain tissue. In this study, the hydrogen-bonded organic framework PFC-71 is synthesized and modified on CFEs through π-π stacking interactions with carboxylated carbon nanotubes (CNT-COOH). It is found that the gating effect and hydrophilicity of PFC-71 provided the CFE with excellent antibiofouling properties. As a result, AA exhibited a low oxidation potential of -30mV on the CFE/CNT-COOH/PFC-71, even in the presence of 20mgmL-1 bovine serum albumin. Given the structural advantages of CFE/CNT-COOH/PFC-71, a ratiometric electrochemical strategy for AA is established, enabling the in situ assay of cerebral AA in a middle cerebral artery occlusion (MCAO) model with high accuracy and stability.

Thermo- and pH-Responsible Gels for Efficient Protein Adsorption and Desorption

Protein adsorption behavior was examined on poly(N-isopropylacrylamide-co-sodium methacrylate)-based hydrogels at different temperatures: 5, 20, and 37 °C, and pH: 4.5, 7, and 9.2. The hydrogels, whose covalent skeleton contains pendant anionic units due to the presence of the sodium methacrylate co-monomer, exhibited both thermo- and pH-sensitivity with different extents, which depended on the content of ionizable moieties and the cross-linker density. The hydrogel composition, temperature, and pH influenced the zeta potential of the hydrogels and their swelling properties. The proteins selected for the study, i.e., bovine serum albumin (BSA), ovalbumin (OVA), lysozyme (LYZ), and a monoclonal antibody (mAb2), differed in their aminoacidic composition and conformation, thus in isoelectric point, molecular weight, electrostatic charge, and hydrophobicity. Therefore, the response of their adsorption behavior to changes in the solution properties and the hydrogel composition was different. LYZ exhibited the strongest adsorption of all proteins with a maximum at pH 7 (189.5 mg ggel−1); adsorption of BSA and OVA reached maximum at pH 4.5 (24.4 and 23.5 mg ggel−1), whereas mAb2 was strongly adsorbed at 9.2 (21.7 mg ggel−1). This indicated the possibility of using the hydrogels for pH-mediated separation of proteins differing in charge under mild conditions in a water-rich environment of both the liquid solution and the adsorbed phase. The adsorption affinity of all proteins increased with temperature, which was attributed to the synergistic effects of attractive electrostatic and hydrophobic interactions. That effect was particularly marked for mAb2, for which the temperature change from 5 to 37 °C caused a twentyfold increase in adsorption. In all cases, the proteins could be released from the hydrogel surface by a reduction in temperature, an increase in pH, or a combination of both. This allows for the elimination of the use of salt solution as a desorbing agent, whose presence renders the recycling of buffering solutions difficult.

A unique and convenient electrochemical biosensor for sodium based on a Na+-pumping rhodopsin

Sodium ion (Na+) detection plays a crucial role in various fields, including clinical diagnostics, environmental monitoring, and food quality control. However, existing techniques often lack sensitivity, selectivity, or practicality. This study presents a novel protein-based electrochemical biosensor for selective and quantitative Na+ detection, utilizing the microbial rhodopsin Nonlabens dokdonensis rhodopsin 2 (NdR2) reconstituted into liposome nanoparticles and immobilized on indium tin oxide (ITO) electrodes. Upon light illumination, the biosensor generates photocurrents proportional to the Na+ concentration in the sample. Extensive characterization unveiled the biosensor’s remarkable selectivity towards Na+ over other cationic species, including K+, Ca2+, Mg2+, and Cs+. Quantitative analysis revealed two linear response ranges: 2–50 mM and 50–200 mM, with a detection limit of 75 μM. The biosensor demonstrated exceptional thermal stability, withstanding 50 °C for 90 min with minimal signal deterioration. Long-term storage stability tests further highlighted its robustness, with consistent Na+ response for up to 17 days. Furthermore, the biosensor successfully detected Na+ in fetal bovine serum, although with a distinct photocurrent profile potentially influenced by interfering components. This pioneering work introduces a highly selective, sensitive, and stable protein-based biosensor for Na+ detection, offering promising implications for diverse applications in clinical diagnostics, environmental monitoring, and quality control, while paving the way for further advancements in biosensing technologies.

The Anisotropic Mechanical and Tribological Behaviors of Additively Manufactured (Material Extrusion) Implant-Grade Polyether Ether Ketone (PEEK)

In this study, we investigated the mechanical and tribological properties of the layer-by-layer structure of additively manufactured implant-grade Polyether Ether Ketone (PEEK) through the Material Extrusion (ME) process as a potential substitute for artificial joints. The effective elasticity modulus of the anisotropic 3D-printed PEEK was determined to be 2.505 GPa along the vertical and horizontal build orientations. The lubricated friction and wear performance were assessed using a pin-on-disk test under various loads, including 14, 30, 50, and 70 N, with a sliding speed of 50 mm/s over a total distance of 1 km at 37 °C. The contact parameters between the hemispherical steel pin and 3D-printed PEEK disks, involving contact pressures over the circle of contact, were observed to increase as the load increased. The results indicated that the wear coefficient exhibited a rise from 1.418 × 10−5 to 2.089 × 10−1 as the applied loads increased, signaling a shift from mild to severe wear regimes. Fetal Bovine Serum (FBS) as a lubricant exhibited a mixed mechanism, ascertained through the Stribeck curve, as well as a minimum fluid film thickness of 1.346 nm under an isoviscous–elastic regime, as calculated by the maximum load. Moreover, the mechanism governing wear during sliding, influenced by both normal axial and shear loads, primarily involved adhesion.

High-Throughput Single-Particle Characterization of Aggregation Pathways and the Effects of Inhibitors for Large (Megadalton) Protein Oligomers.

Protein aggregation is involved in many human diseases, but characterizing the sizes and shapes of intermediate oligomers (∼10-100 nm) that are important to the formation of macroscale aggregates like amyloid fibrils is a significant analytical challenge. Here, charge detection mass spectrometry (CDMS) is used to characterize individual conformational states of bovine serum albumin oligomers with up to ∼225 molecules (15 MDa). Elongated, partially folded, and globular conformational families for each oligomer can be readily distinguished based on the extent of charging. The abundances of individual conformers vary with changes in the monomer concentration or by adding aggregation inhibitors, such as SDS, heparin, or MgCl2. These results show the potential of CDMS for investigating intermediate oligomers in protein aggregation processes that are important for understanding aggregate formation and inhibition mechanisms and could accelerate formulation buffer development to prevent the aggregation of biotherapeutics.

Co-Assembled Nanosystems Exhibiting Intrinsic Fluorescence by Complexation of Amino Terpolymer and Its Quaternized Analog with Aggregation-Induced Emission (AIE) Dye.

Aggregation-induced emission dyes (AIEs) have gained significant interest due to their unique optical properties. Upon aggregation, AIEs can exhibit remarkable fluorescence enhancement. These systems are ideal candidates for applications in bioimaging, such as image-guided drug delivery or surgery. Encapsulation of AIEs in polymeric nanocarriers can result in biocompatible and efficient nanosystems. Herein, we report the fabrication of novel nanoaggregates formulated by amino terpolymer and tetraphenylethylene (TPE) AIE in aqueous media. Poly(di(ethylene glycol) methyl ether methacrylate-co-2-(dimethylamino)ethylmethacrylate-co-oligoethylene glycol methyl ether methacrylate), P(DEGMA-co-DMAEMA-co-OEGMA) hydrophilic terpolymer was utilized for the complexation of the sodium tetraphenylethylene 4,4',4″,4‴-tetrasulfonate AIE dye. Fluorescence spectroscopy, physicochemical studies, and self-assembly in aqueous and fetal bovine serum media were carried out. The finely dispersed nanoparticles exhibited enhanced fluorescence compared to the pure dye. To investigate the role of tertiary amino groups in the aggregation phenomenon, the polymer was quaternized, and quaternized polymer nanocarriers were fabricated. The increase in fluorescence intensity indicated stronger interaction between the cationic polymer analog and the dye. A stronger interaction between the nanoparticles and fetal bovine serum was observed in the case of the quaternized polymer. Thus, P(DEGMA-co-DMAEMA-co-OEGMA) formulations are better candidates for bioimaging applications than the quaternized ones, presenting both aggregation-induced emission and less interaction with fetal bovine serum.

Highly efficient removal of trace thallium from surface water by Co@Fe Prussian blue analogue coated membrane

Super trace thallium(I) (Tl+) is still highly toxic and its removal from surface water is challenging. Here, we developed a new adsorptive membrane by immobilizing bimetal (cobalt and iron) Prussian blue analogues (Co@Fe-PBAs) on a polytetrafluoroethylene microporous membrane (Co@Fe-PBAs-M). The prepared membrane displayed precise adsorption of trace Tl+ (50 μg/L) from complex water. A variety of interfering factors, such as water pH, competitive adsorption of positive ions (Na+ and K+) and negative ions (CO32– and PO43-), natural organic matters (e.g., fulvic acid and bovine serum albumin) were evaluated during Tl removal. The composite membrane showed high removal efficiency (over 80 %) during long-term dynamic membrane separation of surface water containing super trace Tl+ (<2.0 μg/L), breaking through the adsorption limitation in ultralow concentration of Tl+. The unique bimetal electron transfer of Co@Fe-PBAs-M reinforced the adsorptive performance to Tl+ through dual ion exchange and intercalation. In the treatment of real Pearl River water containing 0.5 μg/L of Tl+, our membrane effectively reduced the Tl+ concentration to 0.04 μg/L during 6-h continuous separation, which was far below the required level for drinking water (i.e., 0.1 μg/L). This work offers a promising solution for safe drinking water by remedying ultralow Tl+ contaminated surface water.

Cobalt vanadate intertwined in carboxylated multiple-walled carbon nanotubes for simultaneous electrochemical detection of ascorbic acid, dopamine and uric acid

Low-cost transition metal vanadate-based electrochemical sensors have attracted a lot of attention recently. A cobalt vanadate and carboxylated multi-walled carbon nanotube composite (CoV/MWCNTs-COOH) was prepared by an ultrasonic-assisted assembly method. The uniform and dense MWCNTs-COOH attached to the surface of CoV not only combines the large surface area and superior conductivity of MWCNTs-COOH with the excellent electrochemical activity of CoV, but also enhances the redox reaction between CoV/MWCNTs-COOH composite and the analyte through synergistic effect of hydrogen bonding and electrostatic interaction. The electrochemical behaviors of CoV/MWCNTs-COOH composite modified glassy carbon electrode (CoV/MWCNTs-COOH/GCE) were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The simultaneous electrochemical sensing of ascorbic acid (AA), dopamine (DA) and uric acid (UA) on CoV/MWCNTs-COOH/GCE possesses good peak current signals with well-defined peak potentials. The linear ranges of AA, DA, and UA at CoV/MWCNTs-COOH/GCE are 1.0–100.0 μM, and the limits of detection (LODs; S/N = 3) are 0.4 μM, 0.03 μM, and 0.1 μM, respectively. The practicality of the designed sensor was further confirmed by the good recoveries obtained in the simultaneous measurement of actual samples including fetal bovine serum, human serum, urine, and Vitamin C tablets. Overall, the developed electrochemical sensor shows potential therapeutic applications for simultaneous determination of AA, DA and UA in biological fluids.

Investigations on the complexation and binding mechanism of bovine serum albumin with Ag-doped TiO2 nanoparticles.

It is essential to study the interactions between nanoparticles and proteins to better understand the biological interactions of nanoparticles. In this study, we studied the protein adsorption mode on the surface of Ag-doped TiO2 nanoparticles (NPs) using a model protein, bovine serum albumin (BSA). The mechanism of binding BSA to the Ag-doped TiO2 NPs was studied by applying fluorescence quenching, absorbance measurements, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy techniques. The strong binding between BSA and Ag-doped TiO2 NPs was confirmed by a high value of binding constant (K = 2.65 × 105 L mol-1). We also studied the thermal stability of BSA in the presence of the Ag-doped TiO2 NPs. Thermodynamic parameters indicated that the adsorption of BSA on the Ag-doped TiO2 NPs was a spontaneous, natural and exothermic process. The effect of Ag-doped TiO2 NPs on the transportation function of BSA was also studied using a fluorescence spectroscopic technique. Fluorescence spectroscopic data suggested the existence of a strong interaction between BSA and the surface of the Ag-doped TiO2 NPs, which indicated that the binding affinities of some selected amino acids in BSA changed. This, in turn, clearly confirms that the Ag-doped TiO2 NPs affect the transportation capability of BSA in blood.

Optimizing PES microfiltration membranes for sterile filtration: A comparative study of polydopamine coating in acidic and basic conditions to minimize protein adsorption

The increasing need for effective sterile filtration in the pharmaceutical industry calls for advancements in microfiltration (MF) membrane technology that can effectively reduce fouling and preserve essential protein products. Our study highlights the crucial role of improving the hydrophilicity throughout the entire membrane, not just on the surface, to decrease both protein adsorption and fouling. We have developed a facile but effective method for producing hydrophilic porous polyethersulfone (PES) MF membranes using vapor-induced phase separation (VIPS) followed by a hydrophilic coating. By meticulously adjusting the vapor exposure time, we fabricated two specific types of symmetric membranes: a standard one with a mean pore size of 0.22 μm and another designed with slightly larger pores for the subsequent polydopamine (PDA) coating. All membranes developed in this study showed an outstanding sterilization performance (over 99.99999 % bacteria rejection) due to the absence of defects. Our comparative studies of PDA coating in both acidic and basic environments revealed that the PDA-modified membranes in a Tris-HCl buffer (pH 8.0) (PDA-b-PES2M) outperform others in performance of protein microfiltration. While the membrane modified under acidic conditions underwent a gradual degradation of PDA leading to a poor filtration performance, the PDA-b-PES2M membranes showcased remarkable anti-fouling properties, greatly minimizing the adsorption of bovine serum albumin (BSA) and simplifying the removal of adsorbed materials. Our optimized membrane has a great potential for sterile filtration applications where minimizing protein loss is crucial.

A cobalt coordination complex binds on a unique binding site between domain-I and domain-III of serum albumin

Serum albumin binding influences physiological effects and pharmacokinetics of drugs. Major binding sites in serum albumin are sudlow sites I and II, located on domains IIA and IIIA, respectively. However, groove between domain I and III as a binding site is not well studied. In this work, we studied the binding of a cobalt coordination complex (DCoP) with bovine serum albumin (BSA) using multi-spectroscopic methods and molecular docking. DCoP strongly interacts with BSA with association constant of ∼7 × 105M−1. The binding was found to significantly alter protein's conformation and unfolding pathway. Results of this study shows that DCoP binds at the groove formed between domains III and I. We conclude that the groove is a rare binding site for large molecules and coordination complexes. The knowledge of unique binding site of serum albumin enlightens the comprehensive role of protein as a carrier biomacromolecule.

Tissue-Adaptive BSA Hydrogel with Dual Release of PTX and bFGF Promotes Spinal Cord Injury Repair via Glial Scar Inhibition and Axon Regeneration.

Spinal cord injury (SCI) is a severe clinical disease usually accompanied by activated glial scar, neuronal axon rupture, and disabled motor function. To mimic the microenvironment of the SCI injury site, a hydrogel system with a comparable mechanical property to the spinal cord is desirable. Therefore, a novel elastic bovine serum albumin (BSA) hydrogel is fabricated with excellent adhesive, injectable, and biocompatible properties. The hydrogel is used to deliver paclitaxel (PTX) together with basic fibroblast growth factor (bFGF) to inhibit glial scar formation as well as promote axon regeneration and motor function for SCI repair. Due to the specific interaction of BSA with both drugs, bFGF, and PTX can be controllably released from the hydrogel system to achieve an effective concentration at the wound site during the SCI regeneration process. Moreover, benefiting from the combination of PTX and bFGF, this bFGF/PTX@BSA system significantly aided axon repair by promoting the elongation of axons across the glial scar with reduced reactive astrocyte secretion. In addition, remarkable anti-apoptosis of nerve cells is evident with the bFGF/PTX@BSA system. Subsequently, this multi-functionalized drug system significantly improved the motor function of the rats after SCI. These results reveal that bFGF/PTX@BSA is an ideal functionalized material for nerve repair in SCI.

An epitope imprinted electrochemical sensor for highly sensitive and selective determination of prostate-specific antigen.

Asimple method forhighly selective and sensitive prostate-specific antigen (PSA) detection using a molecularly imprinted electrochemical sensor ispresented. The sensor was developed through an epitope imprinted strategy combined with electrochemical measurement techniques. An epitope molecularly imprinted polymer (EMIP) film was constructed on a AuNPs-coated gold electrode surface through electropolymerization, utilizing the C-terminus epitope of PSA (KWIKDTIVANP) as the template molecular and o-phenylenediamine as the functional monomer. The characteristics of EMIP film were investigated by using a scanning electron microscope and electrochemical test methods, including electrochemical impedance spectroscopy and cyclic voltammetry. Key parameters such as electropolymerization cycles, elution and rebinding times, and the molar ratio of template molecular to functional monomer were systematically optimized. The sensor demonstrated a detection limit (LOD) of 0.31 fg/mL and exhibited an excellent linear response towards PSA concentration ranging from 1.0 fg/mL to 0.1 µg/mL. Furthermore, the EMIP sensor showed excellent selectivity against other biological macromolecules, such as bovine serum albumin, human serum albumin, alpha-fetoprotein, and carcinoembryonic antigen. With recoveriesbetween 95.89 and 106.04% for PSA detection in human serums theEMIP/AuNPs/AuE electrochemical sensor showed great potential in real sample analysis.

Influence of albumin concentration on surface characteristics and cellular responses in the pre-incubation of multi-walled carbon nanotubes.

Reliable characterization of protein coronas (PCs) that form when nanomaterials are introduced into biological fluids is a critical step in the development of safe and efficient nanomedicine. We observed that bovine serum albumin (BSA)-coated multi-walled carbon nanotubes (MWCNTs) do not induce cytotoxicity, but have different cellular uptake rates depending on the BSA pretreatment concentration. To determine how these slight differences affect A549 cell responses and intracellular changes, we conducted spectroscopic (circular dichroism and Fourier-transform infrared) and spectrometric (nanoflow liquid chromatography-electrospray ionization-tandem mass spectrometry) analyses. The various characterization techniques conducted in this study reveal the following. (i) The composition ratio of PCs on MWCNTs differs depending on the BSA concentration. (ii) Analysis of the secondary structure of the proteins revealed that the α-helix structure increased with increasing BSA concentration. (iii) Proteomic analysis showed that different biological pathways were activated at levels higher and lower than 5 mg mL-1. Such combined spectroscopic and spectrometric approaches provide an integrated understanding of PC composition as well as how nano/bio-interface states are linked to cellular-level responses. Our results can support reliable and practical applications of nanomedicine development.

Fabrication of ultrafiltration membrane with antibacterial properties by blending Ag/UiO-66-NH2 and bamboo cellulose

Cellulose is a widely available organic substance that forms membranes with excellent hydrophilicity and biocompatibility. However, it is prone to biological contamination because its surface is conducive towards the accumulation of biologically active substances, which has hindered its application potential. In this work, an antimicrobial cellulose-based membrane (Ag/UiO-66-NH2@BCM) with high water flux, high retention rate, and good hydrophilicity was prepared. At an optimal blend ratio of 1 wt% Ag/UiO-66-NH2, the membrane exhibited significant improvements, including a 31% increase in pure water flux, a Bovine Serum Albumin retention rate of 99.6%, and a water flux recovery of 97.4%. Crucially, the membrane demonstrated potent antibacterial, showcasing its broad-spectrum antimicrobial properties. Investigations into the ability of Ag/UiO-66-NH2@BCM to remove Pb2+, Cd2+, and Cr6+ ions from a water column revealed that the maximum adsorption capacity of the monolayer was 405, 390, and 328 mg/g, respectively. The composite membrane demonstrated broad-spectrum and highly effective antimicrobial properties, along with efficient removal of heavy metal ions. The proposed method can be utilized to prepare other composite membranes for water treatment and other fields of membrane separation technology.

Mesoporous Silica Microparticle-Protein Complexes: Effects of Protein Size and Solvent Properties on Diffusion and Loading Efficiency.

Oral administration of protein-based therapeutics is highly desirable due to lower cost, enhanced patient compliance, and convenience. However, the harsh pH environment of the gastrointestinal tract poses significant challenges. Silica-based carriers have emerged as potential candidates for the delivery of protein molecules, owing to their tuneable surface area and pore volume. We explored the use of a commercial mesoporous silica carrier, SYLOID, for the delivery of octreotide and bovine serum albumin (BSA) using a solvent evaporation method in three different solvents. The loading of proteins into SYLOID was driven by diffusion, as described by the Stokes-Einstein equation. Various parameters were investigated, such as protein size, diffusion, and solubility. Additionally, 3D fluorescence confocal imaging was employed to identify fluorescence intensity and protein diffusion within the carrier. Our results indicated that the loading process was influenced by the molecular size of the protein as octreotide exhibited a higher recovery rate (71%) compared to BSA (32%). The methanol-based loading of octreotide showed uniform diffusion into the silica carrier, whereas water and ethanol loading resulted in the drug being concentrated on the surface, as shown by confocal imaging, and further confirmed by scanning electron microscopy (SEM). Pore volume assessment supported these findings, showing that octreotide loaded with methanol had a low pore volume (1.2cc/g). On the other hand, BSA loading was affected by its solubility in the three solvents, its tendency to aggregate, and its low solubility in ethanol and methanol, which resulted in dispersed particle sizes of 223 and 231μm, respectively. This reduced diffusion into the carrier, as confirmed by fluorescence intensity and diffusivity values. This study underscores the importance of protein size, solvent properties, and diffusion characteristics when using porous carriers for protein delivery. Understanding these factors allows for the development of more effective oral protein-based therapeutics by enhancing loading efficiency. This, in turn, will lead to advances in targeted drug delivery and improved patient outcomes.

Adsorption and Morphology Analysis of Bovine Serum Albumin on a Micropillar-Enhanced Quartz Crystal Microbalance.

The adsorption of bovine serum albumin (BSA), a widely used blood plasma protein, onto poly(methyl methacrylate) (PMMA) surface is a fundamental phenomenon attracting increasing interests in molecular biology, cell culture, immunology, diagnostics, and vaccinology. The nanostructured PMMA surfaces have shown a considerable effect on the BSA adsorption process. However, the effect of microstructures (e.g., micropillars) on BSA adsorption has seldom been studied. This research reports on the development of an acoustic resonance based method to explore the adsorption of BSA proteins on PMMA micropillars in terms of surface coverage, apparent binding constants, and pH-induced morphology variation. A theoretical model is developed to understand the frequency changes of QCM induced by BSA adsorption by taking into consideration the effects of the hydrodynamic force and an equivalent BSA/liquid layer formed on the micropillar surface. In addition, it was found that the resonance of micropillars with a quartz crystal microbalance (QCM) substrate significantly influenced BSA adsorption on micropillar surfaces.

Preparation of a thioxoimidazolidin-linked sialoside BSA conjugate for the inhibition of influenza virus

A novel thioxoimidazolidin-linked sialoside bovine serum albumin (WM-BSA) conjugate was synthesized and evaluated as an inhibitor of influenza virus hemagglutinin (HA) and neuraminidase (NA). The multivalent conjugate was prepared by the attachment of thioxoimidazolidin-sialoside monomer (WM) to BSA via adipate linker. Surface plasmon resonance analysis revealed that WM-BSA exhibited potent binding to recombinant influenza HA and NA proteins, with dissociation constants in the submicromolar range. WM-BSA also demonstrated inhibitory activities in the low micromolar range against HA and NA proteins from multiple influenza strains. Investigation of cytopathic effects in infected MDCK cells indicated that WM-BSA possessed antiviral activity with EC50 values of 35–55 μM. The multivalent presentation of sialosides on the BSA scaffold significantly enhanced both the binding affinity and degree of inhibition compared to the monomeric compound WM. These results demonstrate the potential of multivalent sialoside-protein conjugate as a platform for developing novel anti-influenza agent.

Aggregation behavior, interaction forces and physico-chemical parameters of cetyltrimethylammonium chloride in aqueous solution of bovine serum albumin: Impacts of short-chain alcohols and temperature

To better understand the molecular interactions between cetyltrimethylammonium chloride (CTAC) and bovine serum albumin (BSA), we report the alteration of the physicochemical characteristics of CTAC in aqueous BSA solutions in the presence of different alcohols. The analyses were performed using the conductivity method at temperatures ranging from 298.15 to 323.15 K, with 5 K intervals. The critical micelle concentration (CMC) values of the BSA + CTAC systems were found to change with variations in alcohol types, solvent compositions, and temperatures. The CMC values grew with the rising of alcohol contents. The negative free energy changes (∆Gm0) indicated the spontaneous association of the systems in all solvents media. The magnitudes of ∆Hm0 and ∆Sm0, determined from the micellization of the systems, indicated the presence of electrostatic, ion-dipole, and hydrophobic forces. The thermodynamics of transfer (free energy (∆Gm,tr0), enthalpy (∆Hm,tr0), entropy (∆Sm,tr0)), and compensation parameters (∆Hm0,∗ and Tc)—were also calculated, which provided significant insights into the potential interactions between CTAC and BSA in the presence of various alcohol additives. Furthermore, molecular docking studies suggested the binding of CTAC to different BSA binding sites with varying affinities.