Stable and oxidant responsive zwitterionic nanoclusters.
Ontology highlight
ABSTRACT:
SUBMITTER: Huo S
PROVIDER: S-EPMC6397623 | biostudies-literature | 2018 Apr
REPOSITORIES: biostudies-literature
Publications
Stable and oxidant responsive zwitterionic nanoclusters.
Huo Shuaidong S Jiang Ying Y Jiang Ziwen Z Landis Ryan F RF Liang Xing-Jie XJ Rotello Vincent M VM
Nanoscale 20180401 16
Zwitterions are promising ligands for the fabrication of non-toxic and non-interacting biomaterials. Sulfonamide-based monothiol zwitterionic ligands on gold nanocluster (AuNC) surfaces provide nanomaterials with stable colloidal properties and intense red emission in biological environments. The fluorescence intensity of the nanocluster can be modulated by reactive oxygen species (e.g. ˙OH), allowing for quantitative and selective sensing of antioxidants (e.g. ascorbic acid) in real time. ...[more]
Similar Datasets
Project description:Homogeneous gold nanoclusters (Au NCs) have been widely utilized in drug delivery, chemical sensing, bioassays and bio-labeling due to their unique physical and chemical properties. However, few attentions have been paid on their application in detecting protein post-translational modifications. Herein, we developed a homogeneous reaction system with water-soluble zwitterionic Au NCs to capture glycopeptides from the complex biological samples for the first time. The unique characteristics of Au NCs, such as the molecular-like property, the excellent homogeneity in aqueous solution and organic solvent responsive precipitation, the easy preparation in only 4.5 hours, contribute to the high efficiency and high through-put for capturing the targeted glycopeptides. Briefly, the Au NCs and tryptic protein samples were incubated together in a homogeneous aqueous solution and then the glycopeptides were collected by co-precipitation with zwitterionic Au NCs dur-ing gradually dropping addition of acetonitrile. Compared with the conventional heterogeneous system with solid-state ad-sorbents, the number of characterized glycosylation sites was improved 35%. Finally, the MS detection limitation as low as 50 amol was achieved for the tryptic digests of standard glycoprotein (IgG) and 1576 glycosylation sites from 713 glycopro-teins were feasibly identified from only 60 μg mouse liver proteins
2017-03-29 | PXD005635 | Pride
Project description:To avert the poor bioavailability of antibiotics during S. aureus biofilm infections, a series of zwitterionic nanoparticles containing nucleic acid nanostructures were fabricated for the delivery of vancomycin. The nanoparticles were prepared with three main lipids: (i) neutral (soy phosphatidylcholine; P), (ii) positively charged ionizable (1,2-dioleyloxy-3-dimethylaminopropane; D), and (iii) anionic (1,2-dipalmitoyl-sn-glycero-3-phospho((ethyl-1',2',3'-triazole) triethylene glycolmannose; M) or (cholesteryl hemisuccinate; C) lipids. The ratio of the anionic lipid was tuned between 0 and 10 mol %, and its impact on surface charge, size, stability, toxicity, and biofilm sensitivity was evaluated. Under biofilm mimicking conditions, the enzyme degradability (via dynamic light scattering (DLS)), antitoxin (via DLS and spectrophotometry), and antibiotic release profile was assessed. Additionally, biofilm penetration, prevention (in vitro), and eradication (ex vivo) of the vancomycin loaded formulation was investigated. Compared with the unmodified nanoparticles which exhibited the smallest size (188 nm), all three surface modified formulations showed significantly larger sizes (i.e., 222-277 nm). Under simulations of biofilm pH conditions, the mannose modified nanoparticle (PDM 90/5/5) displayed ideal charge reversal from a neutral (+1.69 ± 1.83 mV) to a cationic surface potential (+17.18 ± 2.16 mV) to improve bacteria binding and biofilm penetration. In the presence of relevant bacterial enzymes, the carrier rapidly released the DNA nanoparticles to function as an antitoxin against α-hemolysin. Controlled release of vancomycin prevented biofilm attachment and significantly reduced early stage biofilm formations within 24 h. Enhanced biocompatibility and significant ex vivo potency of the PDM 90/5/5 formulation was also observed. Taken together, these results emphasize the benefit of these nanocarriers as potential therapies against biofilm infections and fills the gap for multifunctional nanocarriers that prevent biofilm infections.
| S-EPMC8753600 | biostudies-literature
Project description:Gold nanoparticles (AuNPs) are used experimentally for non-invasive in vivo Raman monitoring because they show a strong absorbance in the phototherapeutic window (650-850 nm), a feature that is accompanied by a particle size in excess of 100 nm. However, these AuNPs cannot be used clinically because they are likely to persist in mammalian systems and resist excretion. In this work, clustered ultrasmall (sub-5 nm) AuNP constructs for in vivo Raman diagnostic monitoring, which are also suitable for mammalian excretion, were synthesized and characterized. Sub-5 nm octadecyl amine (ODA)-coated AuNPs were clustered using a labile dithiol linker: ethylene glycol bis-mercaptoacetate (EGBMA). Upon clustering via a controlled reaction and finally coating with a polymeric amphiphile, a strong absorbance in the phototherapeutic window was demonstrated, thus showing the potential suitability of the construct for non-invasive in vivo detection and monitoring. The clusters, when labelled with a biphenyl-4-thiol (BPT) Raman tag, were shown to elicit a specific Raman response in plasma and to disaggregate back to sub-5 nm particles under physiological conditions (37 °C, 0.8 mM glutathione, pH 7.4). These data demonstrate the potential of these new AuNP clusters (Raman NanoTheranostics-RaNT) for in vivo applications while being in the excretable size window.
| S-EPMC8471107 | biostudies-literature
Project description:A zwitterionic poly(sulfobetaine-3,4-ethylenedioxythiophene) (PSBEDOT)-based glucose biosensor was fabricated via encapsulating glucose oxidase (GOx) in a one-step electropolymerization method. Integrating conductivity and hydrophilic properties, PSBEDOT provides a great framework for GOx immobilization and stabilization. The anti-fouling, high-sensitivity, and long-term stability properties of PSBEDOT-GOx make it a promising platform for long-term and continuous glucose monitoring.
| S-EPMC5911821 | biostudies-other
Project description:Luminescent copper nanoclusters (Cu NCs) have shown great potential in light-emitting devices (LEDs), chemical sensing, catalysis and biological fields. However, their practical use has been restricted by poor stability, and study on the stability of Cu NCs solid powder along with the mechanism is absent. In this study, stablized Cu NCs powder was first obtained by cation crosslinking method. Compared with the powder synthesized by solvent precipitation method, the stability of Cu NCs powder crosslinked by ionic inducer Ce3+ was enhanced around 100-fold. The storage time when the fluorescence intensity decreased to 85% (T85) was improved from 2 h to 216 h, which is the longest so far. The results of characterizations indicated that the aggregation structure was formed by the binding of Ce3+ with the capping ligands of Cu NCs, which helped in obtaining Ce-Cu NCs powder from aggregate precipitation in solution. Furthermore, this compact structure could avoid the destruction of ambient moisture resulting in long-lasting fluorescence and almost unchanged physical form. This demonstrated that phosphor, with excellent characteristics of unsophisticated synthesis, easy preservation and stable fluorescence, showed great potential in light sources, display technology and especially in latent fingerprints visualization on different substrates for forensic science.
| S-EPMC8708820 | biostudies-literature
Project description:A novel serine protease gene, SBcas3.3, was identified by functional screening of a forest-soil metagenomic library on agar plates supplemented with AZCL-casein. Overproduction in Escherichia coli revealed that the enzyme is produced as a 770-amino-acid precursor which is processed to a mature protease of ~55 kDa. The latter was purified by affinity chromatography for characterization with the azocasein substrate. The enzyme proved to be an alkaline protease showing maximal activity between pH 9 and 10 and at 50°C. Treatment with the chelating agent ethylenediaminetetraacetic acid irreversibly denatured the protease, whose stability was found to depend strictly on calcium ions. The enzyme appeared relatively resistant to denaturing and reducing agents, and its activity was enhanced in the presence of 10 ml/l nonionic detergent (Tween 20, Tween 80, or Triton X-100). Moreover, SBcas3.3 displayed oxidant stability, a feature particularly sought in the detergent and bleaching industries. SBcas3.3 was activated by hydrogen peroxide at concentrations up to 10 g/l and it still retained 30% of activity in 50 g/l H2O2.
| S-EPMC3765597 | biostudies-literature
Project description:BackgroundDiabetes is one of the biggest medical challenges worldwide. The key to efficiently treat type 1 diabetes is to accurately inject insulin according to the blood glucose levels. In this study, we aimed to develop an intelligent insulin-releasing gold nanocluster system that responds to environmental glucose concentrations.ResultsWe employed gold nanoclusters (AuNCs) as a novel carrier nanomaterial by taking advantage of their high drug-loading capacity. We prepared AuNCs in the protection of bovine serum albumin, and we decorated AuNCs with 3-aminophenylboronic acid (PBA) as a glucose-responsive factor. Then we grafted insulin onto the surface to obtain the glucose-responsive insulin-releasing system, AuNC-PBA-Ins complex. The AuNC-PBA-Ins complex exhibited high sensitivity to glucose concentration, and rapidly released insulin in high glucose concentration in vitro. In the type 1 diabetic mouse model in vivo, the AuNC-PBA-Ins complex effectively released insulin and regulated blood glucose level in the normoglycemic state for up to 3 days.ConclusionsWe successfully developed a phenylboronic acid-functionalized gold nanocluster system (AuNC-PBA-Ins) for responsive insulin release and glucose regulation in type 1 diabetes. This nanocluster system mimics the function of blood glucose regulation of pancreas in the body and may have potential applications in the theranostics of diabetes.
| S-EPMC6547569 | biostudies-literature
Project description:We identified a novel paralog of the antioxidant response element transcription factor, Nrf2 in zebrafish. To determine whether the paralogs Nrf2a and Nrf2b regulate different sets of genes, we performed loss-of-function experiments followed by microarray-based gene expression profiling, performed on embryos in which expression of Nrf2a, Nrf2b, or both paralogs was knocked down.
2011-12-20 | GSE32594 | GEO
Project description:In previous studies we demonstrated that exposure to selenomethionine (SeMet) causes developmental toxicities in zebrafish (Danio rerio). The objectives of this study were to establish a dose-response relationship for developmental toxicities in zebrafish after embryo microinjection of Se (8, 16 or 32??g/g dry mass of eggs) in the form of SeMet, and to investigate potential underlying mechanism(s) of SeMet-induced developmental toxicities. A dose-dependent increase in frequencies of mortality and total deformities, and reduced hatchability were observed in zebrafish exposed to excess Se via embryo microinjection. The egg Se concentration causing 20% mortality was then used to investigate transcript abundance of proteins involved in antioxidant protection and methylation. Excess Se exposure modified gene expression of oxidant-responsive transcription factors (nuclear factor erythroid 2-related factor nrf2a and nrf2b), and enzymes involved in cellular methylation (methionine adenosyltransferase mat1a and mat2ab) in zebrafish larvae. Notably, excess Se exposure up-regulated transcript abundance of aryl hydrocarbon receptor 2 (ahr2), a signalling pathway involved in the toxicity of dioxin-related compounds. Our findings suggest that oxidative stress or modification of methylation, or a combination of these mechanisms, might be responsible for Se-induced developmental toxicities in fishes.
| S-EPMC4876371 | biostudies-literature
Project description:We identified a novel paralog of the antioxidant response element transcription factor, Nrf2 in zebrafish. To determine whether the paralogs Nrf2a and Nrf2b regulate different sets of genes, we performed loss-of-function experiments followed by microarray-based gene expression profiling, performed on embryos in which expression of Nrf2a, Nrf2b, or both paralogs was knocked down. Embryos at the 1-4 cell stage were injected with 3-5 nl of a control morpholino (MO) or gene-specific MO to knockdown Nrf2a, Nrf2b, or a Nrf2a+b combination. At 48 hpf, triplicate groups of 5 embryos were exposed to 2 M-BM-5M of tert butyl hydroquinone or 2% DSMO for 4 hours. At 52 hpf, embryos were fixed in RNA Later and stored at -80M-BM-0C. RNA was extracted, bioanalyzed, labeled with Cy3 and hybridized to the Agilent V3 4x44K zebrafish microarray (cat. #G2519F-026437) at the Genome Technology Core of the Whitehead Institute (Cambridge, MA). Raw array data obtained from the Whitehead Institute were extracted using Agilent's feature extraction software using background detrending (spatial and multiplicative).Prior to normalization, Cy3 values below 5 were set to 5. The data were then normalized using the non-linear scaling method based on rank invariant probes. After normalization but before statistical analyses, probes not significantly above background in all microarrays were removed (3147 probes in all; based on AgilentM-bM-^@M-^Ys 2.6 standard deviation method). None of the probes were saturated for Cy3 signal on any microarray, so no further filtering was applied. There were a total of 40,456 probes for statistical analyses. Statistical tests were performed using MeV v4. Data were log transformed and median centered for each probe. An ANOVA was run for morpholino injection, with p-value based on 1000 permutations of the data and alpha of 0.01. The probes found significant in the ANOVA were subsequently examined using Rank Product (RP) analysis to identify probes up- and down-regulated by the MO injection For each RP test, a two-class unpaired RP analysis was performed using 100 permutations of the data with a false discovery rate (FDR) M-bM-^IM-$10%.
2011-12-20 | E-GEOD-32594 | biostudies-arrayexpress