Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Fluorescent Mesoporous Nanoparticles for ?-Lactamase Screening Assays.

ABSTRACT: We present a sensitive and rapid screening method for the determination of ?-lactamase activity of antibiotic-resistant bacteria, by designing a pH-sensitive fluorescent dye-doped mesoporous silica nanoparticle encapsulated with penicillin G as a substrate. When penicillin G was hydrolysed by ?-lactamase and converted into penicilloic acid, the acidic environment resulted in fluorescence quenching of the dye. The dye-doped mesoporous nanoparticles not only enhanced the ?-lactamase-catalyzed reaction rate but also stablized the substrate, penicillin G, which degrades into penicilloic acid in a water solution without ?-lactamase. Twentyfive clinical bacterial samples were tested and the antibiotic resistant and susceptible strains were identified. The proposed method may detect the presence of ? -lactamases of clinically relevant samples in less than 1?hour. Moreover, the detection limit of ?-lactamase activity was as low as 7.8×10-4?U/mL, which was determined within two hours.

SUBMITTER: Tummala S

PROVIDER: S-EPMC7582675 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Fluorescent Mesoporous Nanoparticles for β-Lactamase Screening Assays.

Tummala Srikrishna S Huang Wei-An WA Wu Bo-Hong BH Chang Kai-Chih KC Ho Yen-Peng YP

ChemistryOpen 20201023 10

We present a sensitive and rapid screening method for the determination of β-lactamase activity of antibiotic-resistant bacteria, by designing a pH-sensitive fluorescent dye-doped mesoporous silica nanoparticle encapsulated with penicillin G as a substrate. When penicillin G was hydrolysed by β-lactamase and converted into penicilloic acid, the acidic environment resulted in fluorescence quenching of the dye. The dye-doped mesoporous nanoparticles not only enhanced the β-lactamase-catalyzed reac ...[more]

PMID: 33117628

Similar Datasets

Ultrabright NIR fluorescent mesoporous silica nanoparticles.

Project description:Near-infrared (NIR) water-dispersible fluorescent tags are of big importance for biomedical imaging. Bright, stable, biocompatible NIR fluorescent nanoparticles have great translation potential to improve diagnosis of early stages of different diseases. Here we report on the synthesis of exceptionally bright ("ultrabright") fluorescent meso(nano)porous silica nanoparticles of 28 ± 3 nm in diameter. The NIR fluorescent dye LS277 is encapsulated inside these silica nanoparticles. The wavelengths of the maximum excitation/fluorescence of the particles are 804/815 nm. The absorptivity coefficient of the particles is 2.1 × 108 M-1 cm-1 at 805 nm and the quantum yield of the dye increased by a factor of 5 after encapsulating to 1.5%. The fluorescent brightness of these particles is more than 2000× higher than the fluorescence of one molecule of LS277 in water. When exited in NIR spectral region (>700 nm), these particles are up to 4× brighter than QD800 commercial quantum dots emitting at 800 nm. We demonstrate that the synthesized NIR mesoporous silica nanoparticles easily internalize 4T1luc breast tumor cells, and remain bright for more than 9 weeks whereas the dye is completely bleached by that time.

| S-EPMC7331230 | biostudies-literature

Ultrabright fluorescent mesoporous silica nanoparticles for prescreening of cervical cancer.

Project description:UNLABELLED:We report on the first functional use of recently introduced ultrabright fluorescent mesoporous silica nanoparticles, which are functionalized with folic acid, to distinguish cancerous and precancerous cervical epithelial cells from normal cells. The high brightness of the particles is advantageous for fast and reliable identification of both precancerous and cancerous cells. Normal and cancer cells were isolated from three healthy women and three cancer patients. Three precancerous cell lines were derived by immortalization of primary cultures of normal cells with human papillomavirus type-16 (HPV-16) DNA. We observed substantially different particle internalization by normal and cancerous/precancerous cells after a short incubation time of 15 minutes. Compared to HPV-DNA and cell pathology tests, which are currently used for prescreening of cervical cancer, we demonstrated that the specificity of our method was similar (94-95%), whereas its sensitivity was significantly better (95-97%) than the sensitivity of those currently used tests (30-80%). FROM THE CLINICAL EDITOR:This team of investigators reports on the development of a new screening test for cervical cancer using ultrabright fluorescent mesoporous silica nanoparticles functionalized with folic acid, enabling significantly better sensitivity (95-97% vs. 30-80%) and maintained specificity (94-95%) compared with current clinical tests. This test should find a way to clinical use in the near future.

| S-EPMC3815984 | biostudies-literature

Adsorption-desorption nano-aptasensors: fluorescent screening assays for ochratoxin A.

Project description:In this study, a FRET-based fluorescent aptasensor for the detection of ochratoxin A (OTA) was optimized based on the quenching efficiency of single-walled carbon nanotubes (SWCNTs) and the binding affinity of aptamers. OTA aptamers were conjugated with quantum dots and adsorbed to the surface of both acid-modified and unmodified SWCNTs. The maximum fluorescence quenching efficiency of the SWCNTs were compared. Acid-modified SWCNTs (amSWCNTs) have moderate quenching efficiency, providing an optimal sensitivity for qualitative fluorescence-enhancement biosensor assays. The binding parameters of the QD-modified OTA aptamers (1.12.2 and A08min) on the surface of amSWCNTs were compared. Based on our results, the A08min aptamer is a better candidate for OTA detection. Using the A08min aptamer, the SWCNT method had a limit of detection (LOD) of 40 nM. The amSWCNT method had a significantly lower LOD of 14 nM. Turn-on fluorescent nano-aptasensors are emerging as an effective diagnostic tool for simple detection of mycotoxins. Nanocomplexes designed for the detection of mycotoxins in solution and paper-based tests have proven to be useful.

| S-EPMC9081825 | biostudies-literature

Controlled Nutrient Delivery to Pancreatic Islets Using Polydopamine-Coated Mesoporous Silica Nanoparticles

Project description:In the present study, we designed a nanoscale platform for the sustained and controlled delivery of nutrients to pancreatic islets-upon transplantation. Our platform consists of a mesoporous silica nanoparticle (MSNP), loaded with glutamine (G), an essential amino acid required for islet survival and function, and capped with polydopamine (PD). To control the release of glutamine, various concentrations (0.5 - 2 mg/mL) of PD and incubation times (0.5 – 2 h) with MSNPs were investigated in terms of pharmacological properties and biological functions. After extensive testing, PD-G-MSNPs made using PD coating of 0.5 mg/mL incubated for 0.5 h resulted in the optimal platform to maintain the islet viability and functionality in vitro. Following syngeneic renal sub-capsule islet transplantation in STZ-diabetic mice, PD-G-MSNPs improved the engraftment of pancreatic islets as well as their function, resulting in re-establishment of glycemic control. Collectively, our data shows that PD-G-MSNPs can support transplanted islets by providing them with a controlled and sustained supply of nutrients.

2023-12-04 | GSE247020 | GEO

Biocompatibility assessment of functionalized magnetic mesoporous silica nanoparticles in human HepaRG cells

Project description:We have employed whole genome microarray expression to distinguish the effect of diversely functionalized magnetic silica nanoparticles on human HepaRG cells. Cells were exposed in vitro, and datasets of differentially expressed genes were identified for NPs versus control samples.

2017-09-23 | GSE98236 | GEO

Virtual Screening and Experimental Testing of B1 Metallo-β-lactamase Inhibitors.

Project description:The global rise of metallo-β-lactamases (MBLs) is problematic due to their ability to inactivate most β-lactam antibiotics. MBL inhibitors that could be coadministered with and restore the efficacy of β-lactams are highly sought after. In this study, we employ virtual screening of candidate MBL inhibitors without thiols or carboxylates to avoid off-target effects using the Avalanche software package, followed by experimental validation of the selected compounds. As target enzymes, we chose the clinically relevant B1 MBLs NDM-1, IMP-1, and VIM-2. Among 32 compounds selected from an approximately 1.5 million compound library, 6 exhibited IC50 values less than 40 μM against NDM-1 and/or IMP-1. The most potent inhibitors of NDM-1, IMP-1, and VIM-2 had IC50 values of 19 ± 2, 14 ± 1, and 50 ± 20 μM, respectively. While chemically diverse, the most potent inhibitors all contain combinations of hydroxyl, ketone, ester, amide, or sulfonyl groups. Docking studies suggest that these electron-dense moieties are involved in Zn(II) coordination and interaction with protein residues. These novel scaffolds could serve as the basis for further development of MBL inhibitors. A procedure for renaming NDM-1 residues to conform to the class B β-lactamase (BBL) numbering scheme is also included.

| S-EPMC6527342 | biostudies-literature

Photo- and biophysical studies of lectin-conjugated fluorescent nanoparticles: reduced sensitivity in high density assays.

Project description:Lectin-conjugated, fluorescent silica nanoparticles (fNP) have been developed for carbohydrate-based histopathology evaluations of epithelial tissue biopsies. The fNP platform was selected for its enhanced emissive brightness compared to direct dye labeling. Carbohydrate microarray studies were performed to compare the carbohydrate selectivity of the mannose-recognizing lectin Concanavalin A (ConA) before and after conjugation to fluorescent silica nanoparticles (ConA-fNP). These studies revealed surprisingly low emission intensities upon staining with ConA-fNP compared to those with biotin-ConA/Cy3-streptavidin staining. A series of photophysical and biophysical characterizations of the fNP and ConA-fNP conjugates were performed to probe the low sensitivity from fNP in the microarray assays. Up to 1200 fluorescein (FL) and 80 tetramethylrhodamine (TR) dye molecules were incorporated into 46 nm diameter fNP, yielding emissive brightness values 400 and 35 times larger than the individual dye molecules, respectively. ConA lectin conjugated to carboxylic acid surface-modified nanoparticles covers 15-30% of the fNP surface. The CD spectra and mannose substrate selectivity of ConA conjugated to the fNP differed slightly compared to that of soluble ConA. Although, the high emissive brightness of fNP enhances detection sensitivity for samples with low analyte densities, large fNP diameters limit fNP recruitment and binding to samples with high analyte densities. The high analyte density and nearly two-dimensional target format of carbohydrate microarrays make probe size a critical parameter. In this application, fNP labels afford minimal sensitivity advantage compared to direct dye labeling.

| S-EPMC2980569 | biostudies-literature

Mesoporous metallic rhodium nanoparticles.

Project description:Mesoporous noble metals are an emerging class of cutting-edge nanostructured catalysts due to their abundant exposed active sites and highly accessible surfaces. Although various noble metal (e.g. Pt, Pd and Au) structures have been synthesized by hard- and soft-templating methods, mesoporous rhodium (Rh) nanoparticles have never been generated via chemical reduction, in part due to the relatively high surface energy of rhodium (Rh) metal. Here we describe a simple, scalable route to generate mesoporous Rh by chemical reduction on polymeric micelle templates [poly(ethylene oxide)-b-poly(methyl methacrylate) (PEO-b-PMMA)]. The mesoporous Rh nanoparticles exhibited a ∼2.6 times enhancement for the electrocatalytic oxidation of methanol compared to commercially available Rh catalyst. Surprisingly, the high surface area mesoporous structure of the Rh catalyst was thermally stable up to 400 °C. The combination of high surface area and thermal stability also enables superior catalytic activity for the remediation of nitric oxide (NO) in lean-burn exhaust containing high concentrations of O2.

| S-EPMC5454530 | biostudies-literature

Targeting somatostatin receptors by functionalized mesoporous silica nanoparticles.

Project description:Targeting somatostatin receptors by functionalized mesoporous silica nanoparticles.

| PRJEB23155 | ENA

NMR-filtered virtual screening leads to non-metal chelating metallo-β-lactamase inhibitors.

Project description:There are no clinically useful inhibitors of metallo-β-lactamases (MBLs), which are a growing problem because they hydrolyse almost all β-lactam antibacterials. Inhibition by most reported MBL inhibitors involves zinc ion chelation. A structure-based virtual screening approach combined with NMR filtering led to the identification of inhibitors of the clinically relevant Verona Integron-encoded MBL (VIM)-2. Crystallographic analyses reveal a new mode of MBL inhibition involving binding adjacent to the active site zinc ions, but which does not involve metal chelation. The results will aid efforts to develop new types of clinically useful inhibitors targeting MBLs/MBL-fold metallo-enzymes involved in antibacterial and anticancer drug resistance.

| S-EPMC5369532 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data