- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Attomolar Detection of Low-Molecular Weight Antibiotics Using Midinfrared-Resonant Toroidal Plasmonic Metachip Technology
摘要： Plasmonic metamaterials can be used to enhance midinfrared sensors and detectors for immunosensing applications. The major challenge with them is to integrate these technologies in low-cost, compact, and promising platforms. As an emerging technique, we utilize toroidal resonant plasmonic metamaterials to develop an ultrasensitive label-free analytical platform for the detection of specific antibiotics in the midinfrared spectra. Taking advantage of the unique sensitivity of robustly squeezed electromagnetic fields in the toroidal plasmonic meta-atoms, we demonstrate that our proposed approach based on toroidal metastructures provides recognition of extremely-low-weight (approximately 0.6 KDa) biological targets at attomolar densities. We envisage that this understanding extends the capabilities of plasmonic metamaterials to analyze the presence of specific biological molecules and organisms with ultrahigh precision.
关键词： midinfrared sensors,Plasmonic metamaterials,ultrasensitive label-free analytical platform,antibiotics detection,toroidal resonant plasmonic metamaterials
更新于2025-09-11 14:15:04
-
Hybrid Plasmonic Photoreactors as Visible Light-Mediated Bactericides
摘要： Photocatalytic compounds and complexes, such as tris(bipyridine)ruthenium(II), [Ru(bpy)3]2+, have recently received attention as light-mediated bactericides that can help to address the need for new antibacterial strategies. We demonstrate in this work that the bactericidal efficacy of [Ru(bpy)3]2+ and the control of its antibacterial function can be significantly enhanced through combination with a plasmonic nanoantenna. We report strong, visible light-controlled bacterial inactivation with a nanocomposite design that incorporates [Ru(bpy)3]2+ as photocatalyst and a Ag nanoparticle (NP) core as light-concentrating nanoantenna into a plasmonic hybrid photoreactor. The hybrid photoreactor platform is facilitated by a self-assembled lipid membrane that encapsulates the Ag NP and binds the photocatalyst. The lipid membrane renders the nanocomposite biocompatible in the absence of resonant illumination. Upon illumination, the plasmon-enhanced photoexcitation of the metal-to-ligand-charge-transfer band of [Ru(bpy)3]2+ prepares the reactive excited state of the complex that oxidizes the nanocomposite membrane and increases its permeability. The photooxidation induces the release of [Ru(bpy)3]2+, Ag+, and peroxidized lipids into the ambient medium, where they interact synergistically to inactivate bacteria. We measured seven orders of magnitude decrease in Gram-positive Arthrobacter sp. and four orders of magnitude decrease in Gram-negative Escherichia coli (E. coli) colony forming units (CFUs) with the photoreactor bactericides after 1-hour of visible light illumination. In both cases the photoreactor exceeds the bactericidal standard of a log reduction value (LRV) of 3, and surpasses the antibacterial effect of free Ag NPs or [Ru(bpy)3]2+ by more than four orders of magnitude. We also implement the inactivation of a bacterial thin film in a proof-of-concept study.
关键词： antibiotics,biofilm,controlled release,sterilization,photocatalyst,antibacterial,nanoantenna
更新于2025-09-11 14:15:04
-
UV light assisted antibiotics for eradication of in vitro biofilms
摘要： The overuse of antibiotics is accelerating the bacterial resistance, and therefore there is a need to reduce the amount of antibiotics used for treatment. Here, we demonstrate in vitro that specific wavelengths in a narrow range around 296 nm are able to eradicate bacteria in the biofilm state (grown for 24 hours) more effectively, than antibiotics and the combination of irradiation and antibiotics is even better, introducing a novel concept light assisted antibiotics. The investigated wavelength range was 249 nm to 338 nm with an approximate step of 5 nm. The novel concept that consists of a UV irradiation treatment followed by a tobramycin treatment can significantly reduce the amount of antibiotics needed for eradicating mature bacterial biofilms. The efficiency of the proposed light assisted antibiotics method was compared to combinatory antibiotic treatment and highly concentrated antibiotic monotherapy. The eradication efficacies, on mature biofilms, achieved by light assisted antibiotic and by the antibiotic monotherapy at approximately 10-fold higher concentration, were equivalent. The present achievement could motivate the development of light assisted antibiotic treatments for treating infections.
关键词： UV light,light assisted antibiotics,Pseudomonas aeruginosa,biofilm eradication,antibiotics
更新于2025-09-10 09:29:36
-
Grain-like bismuth-rich bismuth/bismuth oxychlorides intra-heterojunction: Efficacious solar-light-driven photodegradation of fluoroquinolone antibiotics and 2-level factorial approach
摘要： The grain-like BiOCl (60%)–Bi 24 O 31 Cl 10 (40%) intra-heterojunction nanophotocatalyst was fabricated by a facile one-pot combustion route using sorbitol fuel. It was characterized by the utilization of XRD, FESEM, PSD, BET–BJH and DRS, which proved its successful synthesis. The solar-light-driven photocatalytic activity of BiOCl (60%)–Bi 24 O 31 Cl 10 (40%) was appraised through the destruction of fluoroquinolone antibiotics (FQAs) such as ciprofloxacin, ofloxacin and levofloxacin as persistent and resisting emerging pollutants in an aqueous solution. Consequences obtained were implied to its prominent performance. To investigate the individual and interplay influences of the input operating parameters (catalyst loading, initial pollutant concentration, initial pH and reaction time), the modelling of the photocatalytic destruction of ofloxacin as the response was done by 2-level full factorial experimental design approach. A semi-empirical fourth-order regression model with R 2 = 0.9878 was expressed to relate between the response and independent variables. Results obtained of the mentioned approach demonstrated the high adequacy of the model. The influence of individual parameters and their interactions on the photocatalytic degradation efficiency of ofloxacin was possessed by the main effect graphs, contour and response surface plots. This study not only illustrates a hopeful application of the grain-like BiOCl–Bi 24 O 31 Cl 10 in the solar-light-driven photo-destruction of resistant pollutants such as FQAs but also shows the favourable direction to gain the high-performance.
关键词： Simulated solar light,2-level factorial approach,Rich–bismuth oxychlorides,Grain-like nanophotocatalyst,Fluoroquinolone antibiotics
更新于2025-09-10 09:29:36
-
Toward Point-of-Care Drug Quality Assurance in Developing Countries: Comparison of Liquid Chromatography and Infrared Spectroscopy Quantitation of a Small-Scale Random Sample of Amoxicillin
摘要： Substandard antibiotics are thought to be a major threat to public health in developing countries and a cause of antimicrobial resistance. However, assessing quality outside of a laboratory setting, using simple equipment, is challenging. The aim of this study was to validate the use of a portable Fourier transform infrared (FT-IR) spectrometer for the identification of substandard antibiotics. Results are presented for amoxicillin packages from Haiti, Ghana, Sierra Leone, Democratic Republic of Congo, India, Papua New Guinea, and Ethiopia collected over the course of 6 months in 2017, including two field trips with the FT-IR to Ghana and Sierra Leone. Canadian samples were used as a control. Regarding drug quality, of 290 individual capsules of amoxicillin analyzed, 13 were found to be substandard with total active pharmaceutical ingredients (API) lying outside the acceptable range of 90–110%. Of these 13, four were below 80% API. The FT-IR reliably identified these outliers and was found to yield results in good agreement with the established pharmacopeia liquid chromatography protocol. We conclude that the portable FT-IR may be suitable to intercept substandard antibiotics in developing countries where more sophisticated techniques are not readily available.
关键词： developing countries,amoxicillin,portable FT-IR spectrometer,antimicrobial resistance,substandard antibiotics
更新于2025-09-09 09:28:46
-
Design of a Highly-Stable Pillar-Layer Zn(II) Porous Framework for Rapid, Reversible, and Multi-Responsive Luminescent Sensor in Water
摘要： The Hard-Soft-Acid-Base (HSAB) and dual-ligand strategies have been used to construct a pillar-layer luminescent metal–organic framework (MOF) {[Zn2(TRZ)2(DBTDC-O2)]?DMAc}n (1), in which H2DBTDC-O2 = S,S-dioxodibenzothiophen-3,7-dicarboxylic acid and HTRZ = 1,2,4-triazole. Thanks to its high stability in water and quadrangle microporous channels, MOF 1 can be served as a platform of recyclable multi-responsive luminescent sensor for Fe3+, Al3+, SiF6 2–, Cr2O7 2–, nitrofurantoin (NFT), and nitrofurazone (NFZ) in water. This is the first MOF-based sensor for detecting SiF6 2– anion via luminescent enhancement effect. Significantly, 1 also represents a unique example to probe NFZ or NFT by using transition metal MOFs in water, which exhibits the most sensitive sensing ability for NFZ (Ksv = 5.2 × 104 M–1) and NFT (Ksv = 1.8 × 105 M–1) via luminescent quenching.
关键词： Multi-responsive,Metal–organic framework,Water stability,Antibiotics detection,Luminescent sensor
更新于2025-09-09 09:28:46