Effect Of Bovine Serum Albumin Research Articles

Effect of different concentrations of bovine serum albumin on freezing of goat semen

Objective. Evaluate the effect of Bovine Serum Albumin (BSA) concentration on the freezability of goat semen in a Tris-based lyophilized preservative-diluter, without performing seminal washing, compared with a control preservative-diluter of lactose-skimmed milk (DC), removing the seminal plasma by centrifugation. Materials and methods. It will cover 90 ejaculates, volume, motility, concentration, viability, and sperm morphology. The fit ejaculates were mixed and the pool divided into five portions, each receiving one of 4 lyophilized combinations based on Tris-Glucose-Ac. Citrus and Glycerol with different concentrations of BSA (0.1%, 0.5%, 1% and 2%) or DC. It was frozen in 0.1 ml pellets in nitrogen vapors, and after 2 min., They were stored in liquid nitrogen until thawing 7 days later, the following were determined: motility percentage (30, 120 and 240 minutes), viability, damaged acrosomes and total anomalies (30 and 120 minutes) and were compared using a Binary Logistic Regression model. Results. The highest sperm motility and viability (p <0.05) in the three times was for 0.5%, 1% and 2% of BSA, which were higher than 0.1% of BSA and DC. Damages acrosome and total abnormalities at 30 and 120 minutes were lower (p <0.05) for 0.5%, 1% and 2% of BSA compared to 0.1% and DC. Conclusion. The cryopreservation of goat semen does not require seminal washing by centrifugation if 0.5-2% BSA is used as a membrane protector in a lyophilized dilute-conservative based on Tris-Glucose-Citric Acid and Glycerol.

Effect of bovine serum albumin on gallic acid and tannic acid radical scavenging properties and binding kinetics with 2,2-diphenyl-1-picrylhydrazyl

A detailed study on gallic acid (GA), tannic acid (TA) antioxidant properties, and binding kinetics with 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙) in the presence of bovine serum albumin (BSA) was performed using electronic absorption (UV/Vis), fluorescence, and Fourier transform infrared (FTIR), spectroscopy methods. The effective concentration (EC50), antioxidant reducing power (ARP), stoichiometry (EC100), and the number of reduced DPPH˙(n) were determined using the DPPH˙ assay. It was shown that the antioxidant efficacy of GA/TA reduces slightly in the presence of BSA. However, the duration of the antioxidant activity of GA/TA increases as a result of the complex formation with BSA. The concentration of free and BSA-bound GA/TA was determined using fluorescence spectra. The rate constant (kobs), which describes the main reaction between antioxidant and DPPH˙, and the second-order rate constant (k2) were determined. FTIR studies showed that the binding of GA/TA with BSA causes conformational changes in the secondary structure of the protein (decrease of α-helixes, an increase of β-sheet structures). Moreover, TA induces more pronounced effects compared to GA.

Determining role of structure in the stability increase of purple sweet potato anthocyanins bound to proteins

AbstractThe stability of anthocyanins is poor, seriously affecting their biological activity. The effect of bovine serum albumin (BSA) on the stability of purple sweet potato anthocyanins (PSPA) and its mechanism of action was investigated. Eleven anthocyanins in purple sweet potato were identified, and the stability of PSPAs with different structures combined with BSA was analyzed separately. The results showed an interaction between BSA and PSPA by UV absorption and fluorescence spectra, in which PSPA could cause a fluorescence burst of BSA, and the binding of PSPA to BSA was in the form of 1:1. In addition, the interactions are spontaneous, and hydrophobic interactions dominate. The binding amount study showed that 1 mol/L of BSA binds 3 mol/L of PSPA. The results of zeta potential and particle size showed that the absolute value of the possibility was around 30 mV, and BSA could combine with PSPA to form nanoparticles with high stability. Molecular docking analysis showed that PSPA could be well embedded in the structural cavities of BSA. The binding sites were near sites I and II, hydrogen bonding and hydrophobic interactions act as the main drivers of binding. Finally, after binding, BSA could effectively improve the stability of PSPA, especially for different structures of PSPA. The binding of diacylated anthocyanins was more stable than monoacylated ones, peonidin was more stable than cyanidin, and caffeoyl was more stable compared to p‐hydroxybenzoyl and feruloyl.

High-concentration bovine serum albumin enhances fertilization ability of cold-stored rat sperm.

Cold transport of the cauda epididymides is a useful technique for shipping laboratory rat sperm. Cold transport of rat sperm avoids potential risks of microbiological infection, animal escape or death, and animal welfare issues. Previously, we reported that a cold-storage solution containing dimethyl sulfoxide and quercetin maintained the fertility of cold-stored rat sperm. However, cold-stored rat sperm exhibited a decreased fertilization rate after 24-h storage. To recover the fertility of cold-stored sperm, we focused on the effects of bovine serum albumin (BSA), a cholesterol acceptor that induces sperm capacitation. We sought to determine the optimal concentration of BSA in fertilization medium based on the fertility of cold-stored rat sperm. High concentrations of BSA (40 mg/ml) enhanced the fertilization rate of cold-stored rat sperm and maintained sperm fertility for 144 h. Embryos derived from cold-stored and BSA-treated sperm normally developed into pups after embryo transfer. In summary, high BSA concentrations enhanced the fertility of cold-stored rat sperm and prolonged the storage period to 144 h, thereby expanding the transportable region for genetically engineered rats.

In Vivo Wound Healing in Drosophila melanogaster and Mouse Models: Synergistic Effect of Bovine Serum Albumin and Graphene Quantum Dots.

Bovine serum albumin (BSA)-based biomaterials have garnered significant attention for their remarkable potential in wound healing, primarily due to their effective biological actions in addressing the skin inflammation phase and mitigating hypoalbuminemia. Motivated by these attributes, a nanocomposite hydrogel is developed by blending BSA with poly(vinyl alcohol) (PVA), complemented by the incorporation of graphene quantum dot (GQD). The FTIR study establishes a hydrogen-bonding interaction between the -NH2 groups of BSA and the -OH group of PVA. Microscopic investigations establish that the dispersion of GQDs with an average size of 22.5 nm results in smoothening of the surface of the nanocomposite. The nanocomposite hydrogel reveals excellent swelling attributes of about 920% in a period of 6 h due to its optimum cross-linking condition. Furthermore, the hydrogel exhibits a water vapor transmission rate of 8.45 mg cm-2 h-1, akin to the transmission rate of wounded skin. The PVA/BSA@GQD nanocomposite's antibacterial efficacy is evaluated against Morganella morganii bacteria, showing 99% killing, while its cytotoxicity assay against HeLa cells exhibited a minimum cell viability of 76% at a 20 μM concentration, which is ideal for a wound dressing material. In vivo wound healing investigations are conducted on Drosophila, showcasing a 100% wound surface closure within 4 h. This outcome is further substantiated through in vivo studies involving mice, where complete re-epithelialization is achieved within a span of 13 days. The combined results establish the PVA/BSA@GQD nanocomposite as a potential wound dressing material.

Influence of solution and operating conditions on the treatment of aquaculture wastewater using direct contact membrane distillation: Ammonia rejection and membrane fouling

In the context of recirculating aquaculture, the timely and efficient treatment of ammonia nitrogen, which is a key factor influencing the survival of aquaculture organisms, has become a critical issue that must be addressed. This study aimed to comparatively investigate the interactive effects of bovine serum albumin (BSA) concentration, ammonia concentration, pH, temperature, and flow rate on the efficiency and membrane fouling during ammonia rejection by direct contact membrane distillation (DCMD) in the presence or absence of BSA. The results showed that the elevation of ammonia nitrogen concentration, regardless of the presence of BSA in the solution, led to an increase in concentration polarization, resulting in elevated rejection for ammonia nitrogen and aggravated membrane fouling. Moreover, the conditions of ammonia rejection that were found to be more favorable included lower temperature, pH, and flow rate. Among them, temperature and pH change primarily impacted ammonia solubility, which were the two factors with the significant influence on DCMD's ability to reject ammonia. In the presence of BSA, significant alterations were observed in the rejection of ammonia nitrogen and membrane fouling. The inclusion of 5 mg/L BSA resulted in a remarkable 97.5 % rejection of ammonia through hydration force. The elevation of pH led to a notable mitigation of membrane fouling owing to the augmentation of electrostatic force. Furthermore, a strong correlation was found between ammonia concentration, BSA concentration, and DCMD's rejection of ammonia. This study provides valuable insights for the future implementation of DCMD in treating actual ammonia wastewater and mitigating membrane fouling.

Novel vanadyl complexes synthesis, characterization and interactions with bovine serum albumin-effects on STZ- diabetes rats.

Drug-protein interactions are essential since most administered drugs bind abundantly and reversibly to serum albumin and are delivered mainly as a complex with protein. The nature and strength of drug-protein interactions have a big impact on how a drug works biologically. The binding parameters are useful in studying the pharmacological response of drugs and the designing of dosage forms. Serum albumin is regarded as optimal model for in vitro research on drug-protein interaction since it is the main protein that binds medicines and other physiological components. In this perspective, binary complex have been synthesized and characterized, from vanadium metal and acetylacetone(4,4,4-trifluoro-1-(2-theonyl)-1,3-butanedione). Imidazole, 2-Methyl-imidazole, and 2-Ethyl-imidazole auxiliary ligands were employed for the synthesis of ternary complexes. Additionally, UV absorption and fluorescence emission spectroscopy were used to examine the binding interactions between vanadium complexes and Bovine Serum Albumin. The outcomes of the binding studies and spectral approaches were in strong agreement with one another. These complexes upon inoculation into diabetes-induced Wistar rats stabilized their serum glucose levels within 3 days. From various studies, it was discovered that the ordering of glucose-lowering actions of these metal complexes were equivalent. The vanadium ternary metal complex derived from (4,4,4-trifluoro-1-(2-theonyl)-1,3-butanedione) and imidazole as ligands is the best among the other metal vanadium complexes.

Intrinsic peroxidase-like clay mineral nanozyme-triggered cascade bioplatform with enhanced catalytic performance

Recently, the combination of nature enzymes and nanozymes provides new opportunities for constructing new generation of high-performance enzymatic cascade system. Herein, an enzyme cascade bioplatform (GOx-BSA/NAu-2) has been constructed by combining clay mineral nanozymes (nontronite, NAu-2) and natural enzyme (glucose oxidase, GOx). NAu-2 can be used both as a carrier for GOx immobilization and as a mimic of peroxidase (POD) guiding an enzyme cascade bioplatform. Owing to the stabilizing effect of bovine serum albumin (BSA) on enzymes and proper immobilization method, the GOx-BSA/NAu-2 possess better thermal stability, acid-base stability, storage stability and reusability than free enzymes system. Given the substrate channel effect, the acquired GOx-BSA/NAu-2 exhibits higher catalytic efficiency than the BSA/NAu-2 system and the GOx + HRP system. This work provides an efficient and simple reference for the design of clay mineral nanozyme-enzyme bioplatform, and also broadens the application field of clay minerals.

Effects of bovine serum albumin on the corrosion behavior of biodegradable Zn–Cu alloy under dynamic flowing conditions

In vitro experimental evaluation of biodegradable materials must consider the dynamic effects of body fluids and blood in the physiological environment, as biomedical implants are frequently in contact with body fluids and protein adsorption impacts the degradation process. However, little research has been done on the effects of proteins on the corrosion properties of zinc-based alloys under non-static conditions. Herein, the corrosion behavior of the Zn–Cu alloy in Hanks' solution under flowing conditions is examined in relation to the impacts of different bovine serum albumin (BSA) concentrations. Although BSA retards corrosion, the effects of smaller protein concentrations are more significant during the early stage of metal degradation. The corrosion rate of the Zn–Cu alloy decreases with BSA concentrations during immersion before stabilizing. Based on this, a numerical model for the corrosion process of Zn–Cu alloy under dynamic flowing conditions is established. Between the corrosion rates (CR) of Zn–Cu alloy and BSA concentrations (CB) of Hanks’ solution matched a linear connection of the formula CR=α∙CB+β. The results of this research have important significance for the development and application of biodegradable zinc-based biomedical implants.

Effect of bovine serum albumin on the water solubility of hydrophobic corrinoids

Medicinal effects of hydrophobic derivatives of vitamin [Formula: see text] have been insignificantly investigated primarily due to their low solubility in aqueous solutions. One of the ways to increase their water solubility is the complexation with proteins. Here, we report the results of the studies of the reactions between aquacyano cobyrinic acid or monocyano cobesters (i.e., heptamethyl, heptaethyl, heptapropyl, and heptabutyl cobyrinates) and bovine serum albumin (BSA). The weakest binding is observed between aquacyano cobyrinic acid and BSA. In the case of monocyano heptaethyl cobyrinate, one BSA molecule is capable of binding up to six corrinoid molecules preventing its precipitation. Moreover, the pronounced effect of BSA on the solubility in water was observed in the case of monocyano heptapropyl cobyrinate. The absence of the precipitation of monocyano heptabutyl cobyrinate was observed only in the presence of high excess of BSA. BSA modification by diethyl pyrocarbonate, a chemical predominantly reactive toward imidazole motifs, indicated that a major fraction of BSA is bound with monocyano heptaethyl, heptapropyl, and heptabutyl cobyrinates via histidine residues. We showed that nitrosyl complexes of heptaethyl and heptapropyl cobyrinates can be stabilized from precipitation in aqueous solutions using BSA.

The Effect of Bovine Serum Albumin on Benzo[a]pyrene Removal by Lactobacillus Strains.

The aim of this study was to investigate the influence of bovine serum albumin (BSA) on the Lactobacillus-strain-mediated removal of benzo[a]pyrene (BaP). A combination of 0.5 mg/mL of BSA with 1.0 × 1010 CFU/mL bacterial cells had a removal of 49.61% BaP for strain 121, while a combination of 0.4 mg/mL of BSA with 1.0 × 1010 CFU/mL bacterial cells had a removal of 66.09% BaP for strain ML32. The results indicated that the binding of BaP to Lactobacillus-BSA was stable. BSA maintains Lactobacillus activity and BaP removal in the gastrointestinal environment. Heat and ultrasonic treatment of BSA reduced the BaP-binding ability of Lactobacillus-BSA. With the addition of BSA, the surface properties of the two strains affected BaP binding. The Fourier-transform infrared (FTIR) data demonstrated that O-H, N-H, C=O, and P=O groups were involved in the binding of BaP to Lactobacillus-BSA. Scanning electron microscopy (SEM) results revealed that the morphology of Lactobacillus-BSA bound to BaP was maintained. The adsorption of BaP by Lactobacillus-BSA was appropriately described by the pseudo-second-order kinetic model and Freundlich isotherm model. BSA enhances the affinity between the bacterial cells and BaP.

Effects of proteins on magnesium degradation - static vs. dynamic conditions

The interaction between organic molecules and biomaterial surfaces determines the fate of biomaterials during their service life, which is also the research hotspots in the field of biomaterials. To understand the mechanism of protein interaction with magnesium (Mg) degradation, alloying elements, immersion time, protein concentration and surface conditions have been previously considered for the effect of proteins on Mg degradation. However, fluid flow, as one of the critical factors, drew little attention in this case. In the present study, the effect of bovine serum albumin (BSA) and fetal bovine serum (FBS) on Mg degradation was compared under static and dynamic conditions. The results revealed that both BSA and FBS slightly decreased the degradation rate of Mg in Hanks’ balanced salt solution (HBSS) under static immersion due to the protein adsorption and the formation of a Ca/P-rich top layer on Mg surface, whereas under dynamic flow condition the degradation of Mg was significantly accelerated in the presence of BSA or FBS. The reasons seemed to stem from the weakened protein adsorption on Mg surface in this case and the dynamically enhanced interaction between proteins and ions/products in solutions, which largely weaken the combination of the top Ca/P-rich layer with the inner corrosion product layer. These results highlight the importance of testing conditions for Mg characterization in vitro and the synergistic effect between different parameters on Mg degradation.

Influence of bovine serum albumin (BSA) on photodynamic properties of meso-tetrakis(sulfonatophenyl) porphyrin (TPPS4) for picosecond pulse trains

Due to the special interest and unique advantage of bovine serum albumin among various proteins, we carried out researches into effects of bovine serum albumin on photophysical characters of meso-tetrakis(sulfonatophenyl) porphyrin. The laser source we chose is picosecond pulse trains containing 20 subpulses of 70 picoseconds width separating by 13 nanoseconds at 532 nanometers. The theoretical analysis was carried out with a generalized five-level model representing the molecular populating structure. The two-dimensional paraxial field combined with the rate equations was solved by Crank-Nicholson numerical method. The nonlinear optical absorption mechanism in porphyrin is mainly two-step two-photon absorption. We found meso-tetrakis(sulfonatophenyl) porphyrin always shows prominent optical limiting effects binding with or without bovine serum albumin. In the presence of bovine serum albumin, the photophysical parameters of porphyrin get certain influence and cause slight weakening of optical limiting for porphyrin.

Comparison of bovine serum albumin and chitosan effects on calcium phosphate formation in the presence of silver nanoparticles.

The precipitation of calcium phosphates (CaPs) in the presence of more than one type of additive is of interest both from a fundamental point of view and as a possible biomimetic route for the preparation of multicomponent composites in which the activity of the components is preserved. In this study, the effect of bovine serum albumin (BSA) and chitosan (Chi) on the precipitation of CaPs in the presence of silver nanoparticles (AgNPs) stabilized with sodium bis(2-ethylhexyl)sulfosuccinate (AOT-AgNPs), poly(vinylpyrrolidone) (PVP-AgNPs), and citrate (cit-AgNPs) was investigated. In the control system, the precipitation of CaPs occurred in two steps. Amorphous calcium phosphate (ACP) was the first precipitated solid, which transformed into a mixture of calcium-deficient hydroxyapatite (CaDHA) and a smaller amount of octacalcium phosphate (OCP) after 60 min of ageing. Both biomacromolecules inhibited ACP transformation, with Chi being a stronger inhibitor due to its flexible molecular structure. As the concentration of the biomacromolecules increased, the amount of OCP decreased both in the absence and presence of AgNPs. In the presence of cit-AgNPs and two highest BSA concentrations, a change in the composition of the crystalline phase was observed. Calcium hydrogen phosphate dihydrate was formed in the mixture with CaDHA. An effect on the morphology of both the amorphous and crystalline phases was observed. The effect depended on the specific combination of biomacromolecules and differently stabilized AgNP. The results obtained suggest a simple method for fine-tuning the properties of precipitates using different classes of additives. This could be of interest for the biomimetic preparation of multifunctional composites for bone tissue engineering.

Green synthesis of Zn nanoparticles and in situ hybridized with BSA nanoparticles for Baicalein targeted delivery mediated with glutamate receptors to U87‐MG cancer cell lines

Glioblastoma multiforme (GBM) is the most aggressive malignant tumor of the brain. It has different glutamate receptor types. So, these receptors can be a suitable target for GBM treatment. The current study investigated the anticancer effects of bovine serum albumin (BSA)‐Baicalein @Zn‐Glu nanostructure mediated‐GluRs in human glioblastoma U87 cells. BSA‐Ba@Zn‐Glu hybrid nanoparticles (NPs) were set and considered transporters for Baicalein (Ba) active compound delivery. BSA‐Ba@Zn‐Glu NPs were synthesized by a single‐step reduction process. The successful production was confirmed through transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT‐IR), and hemolysis test. The cytotoxic efficacy and apoptosis rate of the nanostructures on U87 glioblastoma cells were investigated by 3‐(4,5‐dimethylthialzol‐a‐yl)‐2,5 diphenyltetrazolium bromide (MTT) and flow cytometry assays, respectively. The synthesized BSA‐Ba@Zn‐Glu nanostructures with a diameter of 142.40 ± 1.91 to 177.10 ± 1.87 nm and zeta potential of −10.57 ± 0.71 to −35.77 ± 0.60 mV are suitable for extravasation into tumor cells. The drug release from the BSA‐Ba@Zn NPs showed controlled and pH‐dependent behavior. In vitro results indicated that the BSA‐Ba@Zn‐Glu NPs significantly reduce cell viability and promote apoptosis of U87 cancer cells. It revealed the cytotoxic effect of the Baicalein and an increase in cellular uptake of nanoparticles by Glu receptors. Zn NPs were synthesized based on a green synthesis method. BSA NPs were used as a nano‐platform for Glu conjugation and Ba drug delivery. BSA‐Ba@Zn‐Glu NPs induce cytotoxicity and apoptosis in human brain cancer cells (U87) in a dose‐dependent manner. Finally, this nanostructure could be served in targeted drug delivery in vivo studies and applied along with other strategies such as X‐ray irradiation as combinational therapies in future studies.

Paper-based device for the selective determination of doxycycline antibiotic based on the turn-on fluorescence of bovine serum albumin-coated copper nanoclusters.

Anenhanced ratiometric fluorescence sensor was built for on-site visual detection of doxycycline (DOX) through the interaction with bovine serum albumin on the surface of red emissive copper nanoclusters. Upon the addition of weakly fluorescent DOX, the red fluorescence from copper nanoclusters gradually decreased through the inner-filter effect (IFE), while a green fluorescence appears and significantly increases, forming an interesting fluorescent isosbestic point, which was assigned to DOX due to sensitization effect of bovine serum albumin. On the basis of this ratiometric fluorescence, the system possessed good limit of detection (LOD) of 45nM and excellent selectivity for DOX over other tetracyclines. Based on these findings, a paper-based sensor has been fabricated for distinct visual detection of trace DOX and combined with smartphone color recognizer for quantitative detection of DOX (LOD = 83nM). This method shows broad application prospects in environmental monitoring and food safety.

Combined effect of chitosan and bovine serum albumin/whey protein isolate on the characteristics and stability of shrimp oil-in-water emulsion.

The effect of bovine serum albumin (BSA) or whey protein isolate (WPI) at various concentrations (0.5%, 1.5%, and 3%; w/v) on the properties of shrimp oil-in-water emulsion was investigated. Both proteins at 1.5% showed the highest emulsifying properties. Moreover, the combined impact of chitosan (CS) at different levels (0.25%, 0.50%, 0.75%, and 1%; w/v) and 1.5% BSA or 1.5% WPI on emulsion properties was also studied. For the same protein used, those stabilized by BSA and WPI in conjunction with CS solution at 0.5% and 0.25% had the highest emulsion stability index, respectively. During storage for 28 days, the BSA-CSstabilized emulsion had higher turbidity, a*, b* but the lowest L* values compared to the WPI-CS counterpart (p<0.05). Emulsion stabilized by the BSA-CS complex showed higher stability, as witnessed by lower d32 and d43 and lower flocculation factor and coalescence index, but it had a lower negative charge than those stabilized by the WPI-CS complex (p<0.05). Oil droplets of the BSA-CS-stabilized emulsion showed a lower extent of size enlargement after storage. Rheological studies revealed viscous, shear-thinning, and non-Newtonian behavior of emulsions. Overall, emulsion stabilized by the BSA-CS complex had higher stability than that stabilized by the WPI-CS complex, and the former could maintain the stability of pigment in shrimp oil to some extent. PRACTICAL APPLICATION: Oil from shrimp hepatopancreas is a rich source of both astaxanthin and polyunsaturated fatty acids with health benefits. It can be used for the preparation of food emulsion, such as mayonnaise, with nutraceutical properties. However, emulsion stability determines the quality of the emulsion. The use of protein (bovine serum albumin) in conjunction with polysaccharides, especially chitosan at appropriate concentrations, was proven to improve shrimp oil-in-water emulsion during extended storage. Additionally, chitosan can act as an antioxidant to prevent the degradation of astaxanthin to some extent. This finding could be potentially beneficial to produce emulsion with high stability using protein-chitosan complexes.

Investigation of the Adhesion‐Modulating Properties of Bovine Serum Albumin (BSA) in Dictyostelium discoideum

Dictyostelium discoideum is a social amoeba commonly used as a model organism in cellular migration studies. Dictyostelium adhesion is mediated by nonspecific interactions, such as Van der Waals forces, as well as specific protein‐mediated interactions between the cell and the substrate. Since adhesive properties of this organism affect its motility, finding ways to manipulate its nonspecific or specific interactions can be useful for future migration experiments. We tested the effects of bovine serum albumin (BSA), which is known to affect nonspecific binding via its interference with electrostatic interactions, on Dictyostelium adhesion. Bacterially‐grown wild‐type cells had increased adhesion when plated on 3% BSA, while axenically‐grown cells exhibited a decrease in adhesion on BSA. To explore why BSA has differential effects on adhesion of Dictyostelium grown under different conditions we tested adhesion of cells lacking one of the specific mediators of attachment, Talin A (TalA). Unlike wild‐type cells, both axenically and bacterially‐grown TalA‐null cells had decreased adhesion on BSA. These data suggest that BSA effects on adhesion may be dependent on TalA in bacterially‐grown cells. Alternatively, since TalA‐null cells have an impaired ability to phagocytose, they may behave more like axenically‐grown cells even when grown on bacteria. In this case, differential effects of BSA may be due to the inherent differences in the adhesion mechanism of cells grown under axenic vs. bacterially‐fed conditions. We are currently examining these possibilities.

Immobilization of Concanavalin A on iron oxide magnetic nanoparticles. Effect of Bovine Serum Albumin in the recognition interactions of the lectin

Iron oxide magnetic nanoparticles are engaging platforms for diverse nanobiotechnological applications, such as proteins separation and glico-biosensing mediated by the surface functionalization with lectins as recognition elements. We present a new strategy for the union of the lectin Concanavalin A (ConA) at the surface of carboxylated iron oxide magnetic nanoparticles (IOMNPs-Ar-COOH). The nanoparticles were obtained by a single step synthesis in the presence of the aryl diazonium salt derived from 4-aminobenzoic acid. The spontaneous grafting allowed to obtain carboxylic acid covalently functionalized magnetite nanoparticles with the carboxylate group exposed to the solution, as was evidenced through the exhaustive characterization by XRD, FTIR, Raman spectroscopy, and TEM analysis. The nanoparticles of Fe3O4 of (6.6 ± 0.7) nm diameter exhibited good magnetic field responsiveness towards an external magnet and stability towards the environmental oxidation. The carboxylic acid groups exposed were used for the conjugation with ConA and participated in its adsorption onto the surface. The ability of ConA to recognize the glycoprotein Glucose Oxidase (GOx) was analyzed in real time by surface plasmon resonance. These results were correlated with the responses obtained by electrochemical methods (electrochemical impedance spectroscopy, and cyclic voltammetry). Considering the possible applications of this nanomaterial, we also evaluate the effect of Bovine Serum Albumin (BSA) in the recognition capability of ConA. Our work let us to conclude that although ConA does not specifically recognize BSA, this protein alters the affinity of ConA for GOx giving an interesting vision of the behaviour of this hybrid nanomaterial in physiological mediums or other matrixes with high concentration of proteins where this nanomaterial could be employed e.g., in a biosensor or the separation of a glycoprotein, among others.

Synthesis and Characterization of Au/Fe Nanostructures and Study of the Effect of Bovine Serum Albumin on Them

Synthesis and Characterization of Au/Fe Nanostructures and Study of the Effect of Bovine Serum Albumin on Them