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Showing papers on "Bovine serum albumin published in 2009"


Journal ArticleDOI
TL;DR: A simple, one-pot, "green" synthetic route, based on the "biomineralization" capability of a common commercially available protein, bovine serum albumin (BSA), has been developed for the preparation of highly stable Au nanocrystals (NCs) with red emission and high quantum yield.
Abstract: A simple, one-pot, "green" synthetic route, based on the "biomineralization" capability of a common commercially available protein, bovine serum albumin (BSA), has been developed for the preparation of highly stable Au nanocrystals (NCs) with red emission and high quantum yield.

2,215 citations


Journal ArticleDOI
TL;DR: A sensor based on a hybrid synthetic-biomolecule that uses arrays of green fluorescent protein and nanoparticles to detect proteins at biorelevant concentrations in both buffer and human serum is reported.
Abstract: There is a direct correlation between protein levels and disease states in human serum, which makes it an attractive target for sensors and diagnostics. However, this is challenging because serum features more than 20,000 proteins, with an overall protein content greater than 1 mM. Here we report a sensor based on a hybrid synthetic-biomolecule that uses arrays of green fluorescent protein and nanoparticles to detect proteins at biorelevant concentrations in both buffer and human serum. Distinct and reproducible fluorescence-response patterns were obtained from five serum proteins (human serum albumin, immunoglobulin G, transferrin, fibrinogen and a-antitrypsin), both in buffer and when spiked into human serum. Using linear discriminant analysis we identified these proteins with an identification accuracy of 100% in buffer and 97% in human serum. The arrays were also able to discriminate between different concentrations of the same protein, as well as a mixture of different proteins in human serum.

425 citations


Journal ArticleDOI
TL;DR: A poly(ethylene glycol) (PEG) hydrogel platform with human neutrophil elastase (HNE) sensitive peptide cross-links formed using thiol-ene photopolymerization rendering the gel degradable at sites of inflammation and protein therapeutics can be physically entrapped within the network and selectively released upon exposure to HNE.

341 citations


Journal ArticleDOI
22 Dec 2009-ACS Nano
TL;DR: The results show the feasibility of tracking multicolored nanoparticles in living endothelial cells and potential usefulness for designing therapeutic nanoparticle cargo to cross the limiting vessel wall endothelial barrier.
Abstract: Caveolae are plasma membrane invaginations prominent in all endothelial cells lining blood vessels. Caveolae characteristically bud to form free cytoplasmic vesicles capable of transporting carrier proteins such as albumin through the cell. However, caveolae size distribution and dynamics in living endothelial cells and ability of caveolae to internalize nanoparticles are not well understood. We demonstrate here the design of a dual-color nanoparticle pair to measure noninvasively caveolae size and dynamics. First, we coated nanoparticles with BSA (bovine serum albumin) to address whether albumin promoted their delivery. Albumin has been shown to bind to protein on endothelial cell surface localized in caveolae and activate albumin endocytosis. Imaging of BSA-coated nanoparticles varying from 20 to 100 nm in diameter in endothelial cells demonstrated that caveolae-mediated nanoparticle uptake was dependent on albumin coating of particles. We also showed that caveolae could accommodate up to 100 nm diameter nanoparticles, a size larger than the diameter of typical caveolae, suggesting compliant property of caveolae. Together, our results show the feasibility of tracking multicolored nanoparticles in living endothelial cells and potential usefulness for designing therapeutic nanoparticle cargo to cross the limiting vessel wall endothelial barrier.

282 citations


Journal ArticleDOI
09 Jul 2009-Langmuir
TL;DR: The formation of BSA-phosphate surface complexes was observed under different BSA adsorption conditions on hydrophobic and hydrophilic surfaces, correlated with the more efficient blocking of nonspecific interactions by the adsorbed BSA layer.
Abstract: We studied the adsorption of bovine serum albumin (BSA) from phosphate-buffered saline (pH 7.4) to hydrophilic and hydrophobic surfaces. Attenuated total reflection Fourier transform infrared spectroscopy, supported by spectral simulation, allowed us to determine with high precision the amount of BSA adsorbed (surface coverage) and its structural composition. The adsorbed BSA molecules had an α-helical structure on both hydrophobic and hydrophilic surfaces but had different molecular conformations and adsorption strengths on the two types of surface. Adsorption of BSA was saturated at around 50% surface coverage on the hydrophobic surface, whereas on the hydrophilic surface the adsorption reached 95%. The BSA molecules adsorbed to the hydrophilic surface with a higher interaction strength than to the hydrophobic surface. Very little adsorbed BSA could be desorbed from the hydrophilic surface, even using 0.1 M sodium dodecyl sulfate, a strong detergent solution. The formation of BSA−phosphate surface compl...

279 citations


Journal ArticleDOI
TL;DR: The interaction between malachite green and bovine serum albumin (BSA) under simulative physiological conditions was investigated by the methods of fluorescence spectroscopy, UV-vis absorption and circular dichroism (CD) spectroscope, which confirmed some micro-environmental and conformational changes of BSA molecules.

276 citations


Journal ArticleDOI
TL;DR: The conjugates showed an order of magnitude increase in antioxidant activity compared to free drug and when combined with intrinsic and ligand-based targeting with dendrimers, these types of GSH sensitive nanodevices can lead to improved drug release profiles and in vivo efficacy.

212 citations


Journal ArticleDOI
TL;DR: Results indicated that MNPs quench BSA FL mainly by a static quenching mechanism and the interaction was spontaneous and the electrostatic interactions played key roles in the reaction process.
Abstract: The interaction of magnetic iron oxide nanoparticles (MNPs) with bovine serum albumin (BSA) was investigated by fluorescence (FL), ultraviolet visible (UV−vis) absorption, Raman, and circular dichroism (CD) spectroscopy. Results indicated that MNPs quench BSA FL mainly by a static quenching mechanism. The FL quenching constants KSV were obtained as 2.44 × 108, 2.41 × 108, and 2.40 × 108 L·mol−1 at 291, 298, and 313 K, respectively. The thermodynamic parameters of enthalpy change ΔHθ, entropy change ΔSθ, and free energy change ΔGθ were −0.90 kJ·mol−1, 157.38 J·mol−1·K−1, and −47.80 kJ·mol−1 (298 K), respectively. The association constant (KA) and the number of binding sites (n) were 7.64 × 107 L·mol−1 and 46.55 at higher concentration of MNPs, and 1.35 × 106 L·mol−1 and 284.74 at lower concentration of MNPs. The analysis results suggested that the interaction was spontaneous and the electrostatic interactions played key roles in the reaction process. In addition, the Raman and CD spectra proved secondary s...

203 citations


Journal ArticleDOI
26 May 2009-ACS Nano
TL;DR: The first application of AMP in the field of nanobiosensors is described, configured with an AMP (Fibronectin, Fn) to detect nucleocapsid protein, a biomarker for severe acute respiratory syndrome (SARS) using In(2)O(3) nanowire based biosensors.
Abstract: Antibody mimic proteins (AMPs) are polypeptides that bind to their target analytes with high affinity and specificity, just like conventional antibodies, but are much smaller in size (2−5 nm, less than 10 kDa). In this report, we describe the first application of AMP in the field of nanobiosensors. In2O3 nanowire based biosensors have been configured with an AMP (Fibronectin, Fn) to detect nucleocapsid (N) protein, a biomarker for severe acute respiratory syndrome (SARS). Using these devices, N protein was detected at subnanomolar concentration in the presence of 44 μM bovine serum albumin as a background. Furthermore, the binding constant of the AMP to Fn was determined from the concentration dependence of the response of our biosensors.

202 citations


Journal ArticleDOI
TL;DR: The results confirm that the brain uptake of DHA or EPA perfused with a physiological buffer is comparable to highly diffusible drugs like diazepam, and can be modulated by albumin binding and chronic dietary DHA intake.

199 citations


Journal ArticleDOI
TL;DR: A molecule that transfers energy through bonds from a donor to an acceptor was prepared with a pH sensitive donor function (fluorescein) and this probe was used to image a conjugate of the probe with bovine serum albumin that was imported into endosomes or in the cytosol using the noncovalently bound carrier.
Abstract: A molecule that transfers energy through bonds from a donor to an acceptor was prepared with a pH sensitive donor function (fluorescein). At pH values above 6.5, minimal energy transfer occurred, and the probe emitted green fluorescence (ca. 520 nm) when excited at the donor (488 nm). Below pH 6.0 however, energy transfer is efficient; hence excitation at the donor causes emission at the acceptor part (600 nm). This probe was used to image a conjugate of the probe with bovine serum albumin that was imported into endosomes or in the cytosol using the noncovalently bound carrier, Pep-1, at 37 and 4 °C, respectively. The more acidic environment of the endosomes was conspicuous from the red fluorescence of the probe.

Journal ArticleDOI
Yan Wei1, Lan Chen1, Ji Chen1, Lin Ge1, Rongqiao He1 
TL;DR: Glycation with D-ribose induces BSA to misfold rapidly and form globular amyloid-like aggregations which play an important role in cytotoxicity to neural cells.
Abstract: D-ribose in cells and human serum participates in glycation of proteins resulting in advanced glycation end products (AGEs) that affect cell metabolism and induce cell death. However, the mechanism by which D-ribose-glycated proteins induce cell death is still unclear. Here, we incubated D-ribose with bovine serum albumin (BSA) and observed changes in the intensity of fluorescence at 410 nm and 425 nm to monitor the formation of D-ribose-glycated BSA. Comparing glycation of BSA with xylose (a control for furanose), glucose and fructose (controls for pyranose), the rate of glycation with D-ribose was the most rapid. Protein intrinsic fluorescence (335 nm), Nitroblue tetrazolium (NBT) assays and Western blotting with anti-AGEs showed that glycation of BSA incubated with D-ribose occurred faster than for the other reducing sugars. Protein intrinsic fluorescence showed marked conformational changes when BSA was incubated with D-ribose. Importantly, observations with atomic force microscopy showed that D-ribose-glycated BSA appeared in globular polymers. Furthermore, a fluorescent assay with Thioflavin T (ThT) showed a remarkable increase in fluorescence at 485 nm in the presence of D-ribose-glycated BSA. However, ThT fluorescence did not show the same marked increase in the presence of xylose or glucose. This suggests that glycation with D-ribose induced BSA to aggregate into globular amyloid-like deposits. As observed by Hoechst 33258 staining, 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and cell counting kit-8 (CCK-8) assay, lactate dehydrogenase (LDH) activity assay, flow cytometry using Annexin V and Propidium Iodide staining and reactive oxygen species (ROS) measurements, the amyloid-like aggregation of glycated BSA induced apoptosis in the neurotypic cell line SH-SY5Y. Glycation with D-ribose induces BSA to misfold rapidly and form globular amyloid-like aggregations which play an important role in cytotoxicity to neural cells.

Journal ArticleDOI
TL;DR: With inocula of 6 to 7 log 10 CFU, most vegetative bacteria and spores tested survived on surfaces for more than 5 weeks, but all were inactivated within 90 min of exposure to hydrogen peroxide vapor in a 100m3 test room even in the presence of 0.3% bovine serum albumin to simulate biological soiling as mentioned in this paper.
Abstract: With inocula of 6 to 7 log10 CFU, most vegetative bacteria and spores tested survived on surfaces for more than 5 weeks, but all were inactivated within 90 min of exposure to hydrogen peroxide vapor in a 100-m3 test room even in the presence of 0.3% bovine serum albumin to simulate biological soiling.

Journal ArticleDOI
TL;DR: With the use of this system, immunoglobulin G was digested at room temperature in 6 min to an extent similar to that achieved with soluble enzyme at 37 degrees C after 24 h.
Abstract: Capillary enzymatic microreactors containing trypsin and endoproteinase LysC immobilized on a porous polymer monolith have been prepared and used for the characterization and identification of proteins such as cytochrome c, bovine serum albumin, and high-molecular weight human immunoglobulin G. The hydrophilicity of diol functionalities originating from the hydrolyzed poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith was not sufficient to avoid adsorption of hydrophobic albumin in a highly aqueous mobile phase. Therefore, this monolith was first hydrophilized via photografting of poly(ethylene glycol) methacrylate followed by photografting of a 4-vinyl-2,2-dimethylazlactone to provide the pore surface with reactive functionalities required for immobilization. This new approach reduced the undesired nonspecific adsorption of proteins and peptides and facilitated control of both the enzyme immobilization and protein digestion processes. The enzymatic reactors were coupled off-line with MALDI/T...

Journal ArticleDOI
TL;DR: In this article, a polyethersulfone (PES) membrane was modified by blending with a copolymer of acrylonitrile (AN) and acrylic acid (AA), followed by grafting bovine serum albumin (BSA) onto the surface of the membrane.

Journal ArticleDOI
TL;DR: A novel protein imprinted polymer for selective recognition of lysozyme was obtained and showed its high selectivity by high-performance liquid chromatography, and the results showed that the column packed with the lyso enzymes imprinted silica beads could effectively separate lyso enzyme from the mixture of ly sozyme-cytochrome c.

Journal ArticleDOI
15 Apr 2009
TL;DR: The experimental results demonstrate that the intermolecular chain associations were formed between alginate chains and protein molecules in either the native form or the heat pre-denatured form, mainly driven by the electrostatic interactions between the oppositely charged amino acids and the anionic polysaccharide macromolecules.
Abstract: The intermolecular interactions between the model protein, bovine serum albumin (BSA) and a biocompatible polysaccharide, sodium alginate, have been investigated. Both the native BSA and the heat pre-denatured BSA were utilized to study, in parallel, the effect of protein conformational change during the protein-alginate complex formation. In this work, a comparison was performed between the native BSA and the heat-denatured BSA incubated sodium alginate mixtures by using zeta potential analyzer, dynamic light scattering (DLS) and turbidimetric analysis of the systems in combination with protein conformational tools, Fourier transform infrared spectroscopy (FT-IR) and size exclusion chromatography (SE-HPLC). The experimental results demonstrate that the intermolecular chain associations were formed between alginate chains and protein molecules in either the native form or the heat pre-denatured form, mainly driven by the electrostatic interactions between the oppositely charged amino acids and the anionic polysaccharide macromolecules. However, the majority of BSA was recovered from the dissociation of protein-alginate complexes and maintained its secondary structure and conformational property. Therefore, alginate is promising as a bioactive compound carrier.

Journal ArticleDOI
TL;DR: A rapid and sensitive indirect competitive enzyme-linked immunosorbent assay (ELISA) method using monoclonal antibody for measuring aflatoxin M1 (AFM1) in milk and milk products has been described.

Journal ArticleDOI
TL;DR: Colloidal uncapped and starch capped CdS (SCdS) nanoparticles were prepared and interaction with bovine serum albumin (BSA) have been studied by UV-visible, FT-IR, steady state, time resolved and synchronous fluorescence spectroscopic measurements.

Journal ArticleDOI
TL;DR: Fluorescence data and UV-vis and CD results showed that the addition of CdTe QDs changed the conformation of BSA and hydrogen bonds and van der Waals forces between the protein and the QDs are the main binding forces stabilizing the complex.

Journal ArticleDOI
TL;DR: In this article, the interactions of mitomycin C (MMC), fluorouracil (FU), mercaptopurine (MP) and doxorubicin hydrochloride (DXR) with bovine serum albumin (BSA) were studied by spectroscopic method.

Journal ArticleDOI
TL;DR: The conformational investigation showed that the presence of CGR resulted in the change of BSA secondary structure and induced the slight unfolding of the polypeptides of protein, which confirmed some micro-environmental and conformational changes of B SA molecules.

Journal ArticleDOI
TL;DR: A novel blend of polycaprolactone and bovine serum albumin (BSA) to form nanofibers containing nerve growth factors is shown, demonstrating the successful incorporation and controlled release potential of PCL BSA scaffolds.

Journal ArticleDOI
TL;DR: The binding of fluorescein sodium salt with three kinds of commercially available bovine serum albumin (BSA) of different grades of purity was investigated at 288, 298 and 313 K by fluorescence and absorption measurements at pH 7.50 as mentioned in this paper.

Journal ArticleDOI
Xiao-Le Han1, Ping Mei2, Yi Liu1, Yi Liu2, Qi Xiao1, Feng-Lei Jiang1, Ran Li1 
TL;DR: It was proved that the probable quenching mechanism of BSA by quinclorac was dynamic quenched and the alterations of protein secondary structure in the presence of QUC were confirmed by the evidences from three-dimensional fluorescence, synchronous fluorescence and CD spectroscopy.

Journal ArticleDOI
TL;DR: The receptor specific interactions of GNR-BBN conjugates provide realistic opportunities in the design and development of in vivo molecular imaging and therapy agents for cancer.
Abstract: Gastrin releasing protein receptor specific bombesin (BBN) peptide-gold nanoconjugates were successfully synthesized using gold nanorods and dithiolated peptide. The gold nanorod-bombesin (GNR-BBN) conjugates showed extraordinary in vitro stabilities against various biomolecules including NaCl, cysteine, histidine, bovine serum albumin, human serum albumin, and dithiothreitol. Quantitative measurements on the binding affinity (IC(50)) of GNR-BBN conjugates toward prostate and breast tumor cells were evaluated. The IC(50) values establish that GNR-BBN conjugates have strong affinity toward the gastrin releasing peptide receptors on both the tumors. Detailed cellular interaction studies of GNR-BBN conjugates revealed that nanorods internalize via a receptor-mediated endocytosis pathway. The receptor specific interactions of GNR-BBN conjugates provide realistic opportunities in the design and development of in vivo molecular imaging and therapy agents for cancer.

Journal ArticleDOI
TL;DR: The results suggest that at low concentrations, warfarin binds at the high-affinity sites (HAS), while low-Affinity binding sites (LAS) are occupied at higher concentrations.

Journal ArticleDOI
TL;DR: In this paper, a small size iron oxide nanoparticle encapsulated in a thin silica shell can offer specific sites to bind protein molecules via surface silanol groups electrostatically at pH 7.4 without severe denaturing of protein structure.
Abstract: Colloid stable magnetic iron oxide nanoparticles, which undergo reversible precipitation from aqueous solution with external magnetic flux, can have many potential applications. However, the lack of generic homogeneous anchoring sites on a magnetic nanoparticle surface for binding of chemical/biochemical species under a wide range of conditions is one key problem. It is shown that a small size iron oxide nanoparticle encapsulated in a thin silica shell can offer specific sites to bind protein molecules via surface silanol groups electrostatically at pH 7.4 without severe denaturing of the bulky protein structure. As a result, we show that a high loading of bovine serum albumin (BSA) of 85 mg/g can be anchored on the silica-encapsulated iron oxide. FTIR, circular dichroism, and binding constant (using site I and site II drugs) measurements show only a small degree of conformational alteration upon immobilization. A partial unfolding of secondary structures on the external sheath of the protein due to compe...


Journal ArticleDOI
Juan Li1, Ping Yao1
16 Apr 2009-Langmuir
TL;DR: A simple and green process of simultaneous formation of albumin nanoparticles and encapsulation of hydrophobic drugs in aqueous solution was developed and a binding of ibuprofen with BSA throughHydrophobic and electrostatic interactions can suppress the precipitation of ib uprofen.
Abstract: A simple and green process of simultaneous formation of albumin nanoparticles and encapsulation of hydrophobic drugs in aqueous solution was developed. Bovine serum albumin (BSA)−dextran conjugates were prepared through the Maillard reaction. Ibuprofen was used as a drug model. The solubility of protonated ibuprofen decreases, and then precipitation occurs when the pH of saturated ibuprofen solution is changed from alkali to acidic value. In the presence of the conjugates, a binding of ibuprofen with BSA through hydrophobic and electrostatic interactions can suppress the precipitation of ibuprofen. After a heat treatment, the gelation of BSA results in the formation of nanoparticles and fixing of the ibuprofen in the core. The nanoparticles were characterized with dynamic and static light scattering, ζ-potential, and transmission electron microscopy. The nanoparticles are of spherical shape having a hydrodynamic diameter of about 70 nm. As much as 0.7 unit weight of ibuprofen can be loaded into one unit w...