Resistance to third generation cephalosporins is widely disseminated in Enterobacteriaceae mainly because of extended-spectrum-β-lactamases (ESBL), plasmid AmpC β-lactamases (PABL), and hyper-production of chromosomal AmpC β-lactamases. Here, we evaluated the performance of rapid test using novel fluorogenic probe assay in simulated blood cultures and compared the results with the phenol red assay using a total of 172 characterized isolates (39 ESBL producers, 13 PABL producers, and 120 susceptible isolates). We prepared a pellet by centrifugation and washing, which can also be used for identification with MALDI-TOF directly from positive blood cultures. After that, we mixed the pellet with fluorogenic probe and measured the fluorescent signal using fluorometer. The fluorogenic probe assay showed higher sensitivity than the phenol red assay (96.2% vs. 71.2%, p < .0001) in 172 simulated blood culture bottles especially in detecting PABL (84.6% vs. 0%, p = .0026) and the turnaround time was 1.5 h. This fluorogenic probe assay, combined with the direct identification of pathogens, could be very useful for rapid identification of isolates and detecting cephalosporin resistance caused by ESBL and PABL directly from positive blood cultures.
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http://dx.doi.org/10.1016/j.mimet.2020.105988 | DOI Listing |
We have employed a triazine-based conjugated polymer network (CPN) for the selective detection of hypochlorite in a semi-aqueous environment. CPNs have been widely employed in gas capture, separation, and adsorption, but the fluorescent properties of CPNs possessing extensive π-conjugated systems tend to be unexplored. Herein, we report the photophysical properties of the CPN and investigate its sensing capability towards hypochlorite.
View Article and Find Full Text PDFTurk J Chem
November 2024
Division of Organic Chemistry, Department of Chemistry, Faculty of Engineering, İstanbul University-Cerrahpaşa, İstanbul, Turkiye.
The detection of intracellular biothiols (cysteine, N-acetyl cysteine, and glutathione) with high selectivity and sensitivity is important to reveal biological functions. In this study, a 2-(2-methoxy-4-methylphenoxy)-3-chloro-5,8-dihydroxynaphthalene-1,4-dione (DDN-O) compound was newly synthesized and used as a fluorogenic probe (detector molecule) in the fluorometric method for the rapid, highly selective, and sensitive determination of biothiols. The intensity values (λ = 260 nm, λ = 620 nm) of the product were measured by adding biothiols to the reaction medium at varying concentrations and the glutathione equivalent thiol content values of each biothiol were calculated.
View Article and Find Full Text PDFMolecules
December 2024
Faculty of Chemistry and Pharmacy, Sofia University "St. Kliment Ohridski", 1 James Bourchier Blvd., 1164 Sofia, Bulgaria.
The development of fluorescence-based methods for bioassays and medical diagnostics requires the design and synthesis of specific markers to target biological microobjects. However, biomolecular recognition in real cellular systems is not always as selective as desired. A new concept for creating fluorescent biomolecular probes, utilizing a fluorogenic dye and biodegradable, biocompatible nanomaterials, is demonstrated.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
We developed a single-molecule enzyme activity assay platform for NAD(P)-dependent oxidoreductases, leveraging a new NAD(P)H-responsive fluorogenic probe optimized for microdevice-based fluorometric detection. This platform enabled the detection of enzyme activities in blood and cerebrospinal fluid (CSF), including lactate dehydrogenase, glucose-6-phosphate dehydrogenase, and hexokinases. We demonstrate its potential for activity-based diagnosis by detecting altered populations of enzyme activity species in blood and CSF from liver damage in brain tumor patients.
View Article and Find Full Text PDFRSC Adv
January 2025
Laboratory of Bioorganic & Natural Products Chemistry, Kobe Pharmaceutical University 4-19-1, Motoyamakita, Higashinada Kobe Hyogo 658-8558 Japan
Fluorogenic probes containing the β-ketoester structure were developed for selective hydrazine detection. The probe equipped with a cyclopropane moiety, having reduced steric hindrance, showed a higher reaction rate than its dimethyl counterpart. In live cell imaging, the probe detects intracellular hydrazine with minimal cytotoxicity.
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