Showing papers on "Bovine serum albumin published in 2022"

Smartphone-Based Electrochemical Immunoassay for Point-of-Care Detection of SARS-CoV-2 Nucleocapsid Protein

Abstract: Large-scale, rapid, and inexpensive serological diagnoses of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) are of great interest in reducing virus transmission at the population level; however, their development is greatly plagued by the lack of available point-of-care methods, leading to low detection efficiency. Herein, an ultrasensitive smartphone-based electrochemical immunoassay is reported for rapid (less than 5 min), low-cost, easy-to-implement detection of the SARS-CoV-2 nucleocapsid protein (SARS-CoV-2 N protein). Specifically, the electrochemical immunoassay was fabricated on a screen-printed carbon electrode coated with electrodeposited gold nanoparticles, followed by incubation of anti-N antibody (Ab) and bovine serum albumin as the working electrode. Accompanied by the antigen–antibody reaction between the SARS-CoV-2 N protein and the Ab, the electron transfer between the electroactive species [Fe(CN)6]3–/4– and the electrode surface is disturbed, resulting in reduced square-wave voltammetry currents at 0.075 V versus the Ag/AgCl reference electrode. The proposed immunoassay provided a good linear range with SARS-CoV-2 N protein concentrations within the scope of 0.01–1000 ng/mL (R2 = 0.9992) and the limit of detection down to 2.6 pg/mL. Moreover, the detection data are wirelessly transmitted to the interface of the smartphone, and the corresponding SARS-CoV-2 N protein concentration value is calculated and displayed. Therefore, the proposed portable detection mode offers great potential for self-differential diagnosis of residents, which will greatly facilitate the effective control and large-scale screening of virus transmission in resource-limited areas.

Simple and effective serum-free medium for sustained expansion of bovine satellite cells for cell cultured meat

Abstract: Cell-cultured meat offers the potential for a more sustainable, ethical, resilient, and healthy food system. However, research and development has been hindered by the lack of serum-free media that enable the robust expansion of relevant cells (e.g., muscle satellite cells) over multiple passages. Recently, a low-cost serum-free media (B8) was described for pluripotent stem cells. Here, B8 is adapted for bovine satellite cells through the addition of a single component, recombinant albumin, which renders it suitable for long-term satellite cell expansion without sacrificing myogenicity. This new media (Beefy-9) maintains cell growth over the entire period tested (seven passages), with an average doubling time of 39 h. Along with demonstrated efficacy for bovine cells, Beefy-9 offers a promising starting-point for developing serum-free media for other meat-relevant species. Ultimately, this work offers a foundation for escaping cultured meat research's reliance on serum, thereby accelerating the field.

Injectable Hydrogel Based on Defect-Rich Multi-Nanozymes for Diabetic Wound Healing via an Oxygen Self-Supplying Cascade Reaction.

Abstract: Diabetic wound healing remains challenging owing to the risk for bacterial infection, hypoxia, excessive glucose levels, and oxidative stress. Glucose-activated cascade reactions can consume glucose and eradicate bacteria, avoiding the direct use of hydrogen peroxide (H2 O2 ) and wound pH restriction on peroxidase-like activity. However, the anoxic microenvironment in diabetic wounds impedes the cascade reaction due to the oxygen (O2 ) dependence of glucose oxidation. Herein, defect-rich molybdenum disulfide nanosheets loaded with bovine serum albumin-modified gold nanoparticle (MoS2 @Au@BSA NSs) heterostructures are designed and anchored onto injectable hydrogels to promote diabetic wound healing through an O2 self-supplying cascade reaction. BSA decoration decreases the particle size of Au, increasing the activity of multiple enzymes. Glucose oxidase-like Au catalyzes the oxidation of glucose into gluconic acid and H2 O2 , which is transformed into a hydroxyl radical (•OH) catalyzed by peroxidase-like MoS2 @Au@BSA to eradicate bacteria. When the wound pH reaches an alkalescent condition, MoS2 @Au@BSA mimicks superoxide dismutase to transform superoxide anions into O2 and H2 O2 , and decomposes endogenous and exogenous H2 O2 into O2 via catalase-like mechanisms, reducing oxidative stress, alleviating hypoxia, and facilitating glucose oxidation. The MoS2 @Au@BSA nanozyme-anchored injectable hydrogel, composed of oxidized dextran and glycol chitosan crosslinked through a Schiff base, significantly accelerates diabetic wound healing.

Biomimic Nanozymes with Tunable Peroxidase-like Activity Based on the Confinement Effect of Metal-Organic Frameworks (MOFs) for Biosensing.

Abstract: Biomimic nanozymes coassembled by peptides or proteins and small active molecules provide an effective strategy to design attractive nanozymes. Although some promising nanozymes have been reported, rational regulation for higher catalytic activity of biomimic nanozymes remains challenging. Hence, we proposed a novel biomimic nanozyme by encapsulating the coassembly of hemin/bovine serum albumin (BSA) in zeolite imidazolate frameworks (ZIF-8) to achieve controllable tailoring of peroxidase-like activity via the confinement effect. The assembly of Hemin@BSA was inspired by the structure of horseradish peroxidase (HRP), in which hemin served as the active cofactor surrounded by BSA as a blocking pocket to construct a favorable hydrophobic space for substrate enrichment. Benefiting from the confinement effect, ZIF-8 with a porous intracavity was identified as the ideal outer layer for Hemin@BSA to accelerate substrate transport and achieve internal circulation of peroxidase-like catalysis, significantly enhancing its peroxidase-like activity. Especially, the precise encapsulation of Hemin@BSA in ZIF-8 could also prevent it from decomposition in harsh environments by rapid crystallization around Hemin@BSA to form a protective shell. Based on the improved peroxidase-like activity of Hemin@BSA@ZIF-8, several applications were successfully performed for the sensitive detection of small molecules including H2O2, glucose, and bisphenol A (BPA). Satisfactory results highlight that using a ZIF-8 outer layer to encapsulate Hemin@BSA offers a very effective and successful strategy to improve the peroxidase-like activity and the stability of biomimic nanozymes, broadening the potential application of biocatalytic metal-organic frameworks (MOFs).

Interaction Characterization of a Tyrosine Kinase Inhibitor Erlotinib with a Model Transport Protein in the Presence of Quercetin: A Drug–Protein and Drug–Drug Interaction Investigation Using Multi-Spectroscopic and Computational Approaches

Abstract: The interaction between erlotinib (ERL) and bovine serum albumin (BSA) was studied in the presence of quercetin (QUR), a flavonoid with antioxidant properties. Ligands bind to the transport protein BSA resulting in competition between different ligands and displacing a bound ligand, resulting in higher plasma concentrations. Therefore, various spectroscopic experiments were conducted in addition to in silico studies to evaluate the interaction behavior of the BSA-ERL system in the presence and absence of QUR. The quenching curve and binding constants values suggest competition between QUR and ERL to bind to BSA. The binding constant for the BSA-ERL system decreased from 2.07 × 104 to 0.02 × 102 in the presence of QUR. The interaction of ERL with BSA at Site II is ruled out based on the site marker studies. The suggested Site on BSA for interaction with ERL is Site I. Stability of the BSA-ERL system was established with molecular dynamic simulation studies for both Site I and Site III interaction. In addition, the analysis can significantly help evaluate the effect of various quercetin-containing foods and supplements during the ERL-treatment regimen. In vitro binding evaluation provides a cheaper alternative approach to investigate ligand-protein interaction before clinical studies.

Near-Infrared Electrogenerated Chemiluminescence from Simple Copper Nanoclusters for Sensitive Alpha-Fetoprotein Sensing.

Abstract: Exploiting low cost, water-soluble, and near-infrared (NIR) emissive electrochemiluminophores (ECLphores) is significantly important for biological applications. In this study, bright and NIR electrogenerated chemiluminescence (ECL) emissive copper nanoclusters (Cu NCs) were synthesized through a facile one-pot wet chemical reduction method. ECL properties of obtained Cu NCs were examined in the presence of potassium persulfate, resulting in maximum intensity at 735 nm, at least 135 nm red-shifted with respect to all other Cu NCs. Electrochemistry, photoluminescence (PL), and spooling ECL spectroscopies were used to track NIR ECL emission of Cu NCs ascribed to the monomeric excited states. Due to the abundant binding sites of bovine serum albumin (BSA) to anchor target biomolecules, a sandwich-type ECL immunosensor was thus fabricated using such BSA-templated Cu NCs as tags and alpha fetoprotein antigen (AFP) as a model protein for the first time. Without assisting any signal amplification strategies, the proposed NIR ECL biosensor exhibited a wide linear range (1-400 ng mL-1) and low detection limit (0.02 ng mL-1) as well as superior selectivity and reproducibility and was successfully applied in real human serum sample determination. This work sets the stage for the development of novel non-noble metal nanoclusters for large-scale and emerging nanotechnology applications.

One step synthesis of efficient red emissive carbon dots and their bovine serum albumin composites with enhanced multi-photon fluorescence for in vivo bioimaging

Abstract: Abstract Efficient red emissive carbon dots (CDs) in aqueous solutions are very scarce for high performance bioimaging applications. In this work, we report a one-step solvothermal treatment to synthesize pure red emissive CDs (FA-CDs) from citric acid and urea in formic acid without complicated purification procedures. Photoluminescence quantum yield (PLQY) of 43.4% was observed in their dimethyl sulfoxide solutions. High PLQY up to 21.9% in aqueous solutions was achieved in their bovine serum albumin (BSA) composites (FA-CDs@BSA) with significantly enhanced multi-photon fluorescence. The strong surface electron-withdrawing structure of FA-CDs caused by the high content of C = O groups contributes for their pure red emission. Owing to the significantly enhanced single and multi-photon red fluorescence and enlarged particle sizes after composing with BSA, in vivo tumor imaging and two-photon fluorescence imaging of blood vessels in mouse ear have been realized via intravenous injection of FA-CDs@BSA aqueous solutions.

One step synthesis of efficient red emissive carbon dots and their bovine serum albumin composites with enhanced multi-photon fluorescence for in vivo bioimaging

Abstract: Abstract Efficient red emissive carbon dots (CDs) in aqueous solutions are very scarce for high performance bioimaging applications. In this work, we report a one-step solvothermal treatment to synthesize pure red emissive CDs (FA-CDs) from citric acid and urea in formic acid without complicated purification procedures. Photoluminescence quantum yield (PLQY) of 43.4% was observed in their dimethyl sulfoxide solutions. High PLQY up to 21.9% in aqueous solutions was achieved in their bovine serum albumin (BSA) composites (FA-CDs@BSA) with significantly enhanced multi-photon fluorescence. The strong surface electron-withdrawing structure of FA-CDs caused by the high content of C = O groups contributes for their pure red emission. Owing to the significantly enhanced single and multi-photon red fluorescence and enlarged particle sizes after composing with BSA, in vivo tumor imaging and two-photon fluorescence imaging of blood vessels in mouse ear have been realized via intravenous injection of FA-CDs@BSA aqueous solutions.

Mechanistic competitive binding interaction study between olmutinib and colchicine with model transport protein using spectroscopic and computer simulation approaches

Abstract: Drug-drug interactions are due to the binding of a drug to plasma proteins displacing another plasma protein-bound drug. Two ligands, olmutinib (OLM) and colchicine (COL), were explored for their binding and displacement interaction with bovine serum albumin (BSA). Olmutinib is a 3rd-generation tyrosine kinase inhibitor (TKI), inhibits EGFR. COL is an anti-mitotic agent used in the treatment of gouty arthritis and has chemotherapeutic properties. The binding of BSA with OLM and COL was evaluated independently and in the presence of each other with spectroscopic and molecular docking and molecular dynamic simulation. Results based on quenching curves, displacement curves, binding constants, and docking results were evaluated. The presence of either drug (OLM or COL) influenced the binding of OLM and COL to BSA. The OLM had a higher binding capacity to BSA compared to COL. The presence of COL in the BSA-OLM system lowered the binding constants in comparison to its binary system. The OLM in the BSA-COL system increased the binding constant values for the system compared to the BSA-COL system. These findings are essential since increased non-bound fraction or reduced free drug fraction availability in the systemic circulation. The interference in the binding of drugs may lead to adverse events or subtherapeutic responses of the drugs.

ROS-Targeted Depression Therapy via BSA-Incubated Ceria Nanoclusters

Abstract: Depression is one of the most fatal mental diseases, and there is currently a lack of efficient drugs for the treatment of depression. Emerging evidence has indicated oxidative stress as a key pathological feature of depression. We targeted reactive oxygen species (ROS) and synthesized CeO2@BSA nanoclusters as a novel antidepression nanodrug via a convenient, green, and highly effective bovine serum albumin (BSA) incubation strategy. CeO2@BSA has ultrasmall size (2 nm) with outstanding ROS scavenging and blood-brain barrier crossing capacity, rapid metabolism, and negligible adverse effects in vitro and in vivo. CeO2@BSA administration alleviates depressive behaviors and depression-related pathological changes of the chronic restraint stress-induced depressive model, suggesting promising therapeutic effects of CeO2@BSA for the treatment of depression. Our study proved the validity by directly using nanodrugs as antidepression drugs instead of using them as a nanocarrier, which greatly expands the application of nanomaterials in depression treatment.

Influence of Rutin, Sinapic Acid, and Naringenin on Binding of Tyrosine Kinase Inhibitor Erlotinib to Bovine Serum Albumin Using Analytical Techniques Along with Computational Approach

Abstract: Flavonoid-containing food supplements are widely used as antioxidants, and the continuous use of these supplements with other drugs can lead to clinically significant interactions between these and other drugs. The medications in systemic circulation are mainly transported by serum albumin, a major transport protein. This study evaluated the interactions of rutin (RUT), naringenin (NAR), and sinapic acid (SIN) with the most abundant transport protein, bovine serum albumin (BSA), and the anticancer drug, the tyrosine kinase inhibitor Erlotinib (ETB), using various analytical methods. Interaction between multiple types of ligands with the transport proteins and competition between themselves can lead to the bound ETB’s displacement from the BSA-binding site, leading to elevated ETB concentrations in the systemic circulation. These elevated drug fractions can lead to adverse events and lower tolerance, and increased resistance to the therapeutic regimen of ETB. The experimental and computational methods, including molecular-docking studies, were used to understand the molecular interactions. The results suggested that the complexes formed were utterly different in the binary and the ternary system. Furthermore, comparing the ternary systems amongst themselves, the spectra differed from each other. They thus inferred that complexes formed between BSA-ETB in the presence of each RUT, NAR, and SIN separately were also different, with the highest value of the reduction in the binding energy in RUT, followed by SIN and then NAR. Thus, we conclude that a competitive binding between the ETB and these flavonoids might influence the ETB pharmacokinetics in cancer patients by increasing ETB tolerance or resistance.

Characterization of protein unfolding by fast cross-linking mass spectrometry using di-ortho-phthalaldehyde cross-linkers

Abstract: Chemical cross-linking of proteins coupled with mass spectrometry is widely used in protein structural analysis. In this study we develop a class of non-hydrolyzable amine-selective di-ortho-phthalaldehyde (DOPA) cross-linkers, one of which is called DOPA2. Cross-linking of proteins with DOPA2 is 60-120 times faster than that with the N-hydroxysuccinimide ester cross-linker DSS. Compared with DSS cross-links, DOPA2 cross-links show better agreement with the crystal structures of tested proteins. More importantly, DOPA2 has unique advantages when working at low pH, low temperature, or in the presence of denaturants. Using staphylococcal nuclease, bovine serum albumin, and bovine pancreatic ribonuclease A, we demonstrate that DOPA2 cross-linking provides abundant spatial information about the conformations of progressively denatured forms of these proteins. Furthermore, DOPA2 cross-linking allows time-course analysis of protein conformational changes during denaturant-induced unfolding.

Wound Microenvironment-Responsive Protein Hydrogel Drug-Loaded System with Accelerating Healing and Antibacterial Property.

Abstract: Growth factors play a vital role in wound healing, and novel hydrogel carriers suitable for growth factors have always been a research hotspot in the wound healthcare field. In this work, a wound microenvironment-responsive hydrogel drug-loading system was constructed by cross-linking of the internal electron-deficient polyester and bovine serum albumin (BSA) via catalyst-free amino-yne bioconjugation. The slightly acidic microenvironment of wound tissues induces the charge removal of BSA chains, thus releasing the basic fibroblast growth factor (bFGF) loaded through electrostatic action. Besides, the BSA chains in the gel network further endow their excellent biocompatibility and biodegradability, also making them more suitable for bFGF loading. The wound caring evaluation of the hydrogel in the full-thickness skin wound indicated that the protein-based hydrogel significantly promotes the proliferation and differentiation of fibroblasts, collagen accumulation, and epidermal layer stacking, thus significantly shortening the healing process. This strategy paved the way for broadening the application of the growth factors in the wound care field.

Platinum nanozyme-hydrogel composite (PtNZHG)-impregnated cascade sensing system for one-step glucose detection in serum, urine, and saliva

Abstract: Bovine serum albumin was used as a nucleation template and stabilizer to prepare platinum nanozymes with high and specific peroxidase-like activity. Together with glucose oxidase, the best-performing nanozyme was entrapped in the 3D porous matrix of a polyethylene glycol hydrogel to fabricate the platinum nanozyme-hydrogel composite (PtNZHG). PtNZHG affords an independent glucose sensing unit, where the catalytic cascade reaction occurs with minimized diffusion resistance of unstable intermediates. This sensing unit was embedded within the confined detection zone of a plastic chip with a 3D hydrophilic fluid path to produce an efficient platform for the stand-alone detection of glucose. The glucose-containing sample was introduced into the device by capillary force, and the colored product generated by the catalytic cascade reaction was concentrated at the detection zone to markedly amplify the colorimetric response and thus increase detection sensitivity (detection range = 0.01–10 mM, detection limit = 3.9 µM). One-step glucose detection could be completed within 15 min, and analysis could be performed using a smartphone camera. The feasibility and practicality of our sensing system were demonstrated by the high recoveries of 83–105% observed for serum, urine, and saliva samples, the high specificity toward glucose without significant interference (<1%) from other sugars, and excellent long-term stability and reproducibility after two-month storage. Thus, our results are expected to advance the monitoring of glucose in human fluids and promote the biosensing of other substrates.

A near-infrared naphthalimide fluorescent probe for targeting the lysosomes of liver cancer cells and specifically selecting HSA

Abstract: Human serum albumin (HSA) plays a pivotal role in various physiological processes of humans, and is generally considered to be one of the early signs of many diseases. Although dysfunction of intracellular lysosome is accompanied in those diseases, the regulation mechanism of HSA in lysosomes still need to be explored. In this work, we report a novel near-infrared naphthalimide probe NI-1 that specifically detects HSA in intracellular lysosomes with the “turn-on” fluorescent sensing modes. In the cell, the N-containing malononitrile group of NI-1 could bind to the lysosome. Moreover, NI-1 can specifically enter the site II hydrophobic cavity of HSA in lysosome. Due to the binding force between NI-1 and HSA, strong steric hindrance and the hydrophobic pocket inside HSA inhibit the twisted internal charge transfer (TICT) effect in the probe itself. Therefore, NI-1 emits strong red fluorescence. More importantly, NI-1 can effectively localize bioimaging of exogenous and endogenous HSA in lysosome. In addition, the novel probe NI-1 achieved a much high selectivity for HSA over bovine serum albumin (BSA), and the interaction mechanism between probe NI-1 and HSA or BSA site II was explained for the first time through molecular docking methods. These results indicate that the probe NI-1 has great potential in exploring further function of HSA for pharmacy and medicine.

A near-infrared naphthalimide fluorescent probe for targeting the lysosomes of liver cancer cells and specifically selecting HSA

Abstract: Human serum albumin (HSA) plays a pivotal role in various physiological processes of humans, and is generally considered to be one of the early signs of many diseases. Although dysfunction of intracellular lysosome is accompanied in those diseases, the regulation mechanism of HSA in lysosomes still need to be explored. In this work, we report a novel near-infrared naphthalimide probe NI-1 that specifically detects HSA in intracellular lysosomes with the “turn-on” fluorescent sensing modes. In the cell, the N-containing malononitrile group of NI-1 could bind to the lysosome. Moreover, NI-1 can specifically enter the site II hydrophobic cavity of HSA in lysosome. Due to the binding force between NI-1 and HSA, strong steric hindrance and the hydrophobic pocket inside HSA inhibit the twisted internal charge transfer (TICT) effect in the probe itself. Therefore, NI-1 emits strong red fluorescence. More importantly, NI-1 can effectively localize bioimaging of exogenous and endogenous HSA in lysosome. In addition, the novel probe NI-1 achieved a much high selectivity for HSA over bovine serum albumin (BSA), and the interaction mechanism between probe NI-1 and HSA or BSA site II was explained for the first time through molecular docking methods. These results indicate that the probe NI-1 has great potential in exploring further function of HSA for pharmacy and medicine.