Sensitized Fluorescence

Human serum albumin (HSA) is regarded as a useful biomarker for rapid medical diagnosis of various disorders mainly related to the kidneys and liver. Hence, it is crucial to identify and monitor the HSA level in complex biofluids (urine and blood samples) using a simple approach. Herein, we have designed and synthesized an intramolecular charge transfer (ICT) based environment-sensitive fluorescent molecular probe, ( E )-2-(3-(2-(5-methoxy-1 H -indol-3-yl)vinyl)-5,5-dimethylcyclohex-2-en-1-ylidene)malononitrile (DCI-MIN), that can selectively interact with HSA in PBS buffer solution and exhibit a ∼78-fold enhancement in fluorescence intensity with a significant Stokes shift (∼126 nm), which is important to avoid interference from the excitation light...

Ferroptosis is a form of regulatory cell death that relies on iron and reactive oxygen species (ROS) to inhibit tumors. The present study aimed to investigate whether icariin-curcumol could be a novel ferroptosis inducer in tumor inhibition. Various concentrations of icariin-curcumol were used to stimulate prostate cell lines (RWPE-2, PC-3, VCAP and DU145). Small interfering negative control (si-NC) and si-nuclear factor erythroid 2-related factor 2 (Nrf2) were used to transfect DU145 cells. Cell viability was determined by using cell counting kit-8...

Multidrug-resistant tuberculosis (MDR-TB) is an essential cause of tuberculosis treatment failure and death of tuberculosis patients. The rapid and reliable profiling of Mycobacterium tuberculosis (MTB) drug resistance in the early stage is a critical research area for public health. Then, most traditional approaches for detecting MTB are time-consuming and costly, leading to the inappropriate therapeutic schedule resting on the ambiguous information of MTB drug resistance, increasing patient economic burden, morbidity, and mortality...

As a new form of regulated cell death, ferroptosis is closely related to various diseases. Tracing ferroptosis related biological behavior is helpful to better understand this process and its related biology. Considering that ferroptosis is featured with remarkable lipid peroxidation which can easily change the membranes' compositions and structures, it is potential to detect intracellular environmental changes for direct assessment of ferroptosis. In view of the close relationship between endoplasmic reticulum (ER) and ferroptosis, we designed an ER-targeted and polarity-sensitive fluorescent probe SBD-CH, which has superior photostability and can respond to polarity with high selectivity without the affection of viscosity...

High fluorescence intensity microspheres such as aggregation-induced emission fluorescence microspheres (AIEFM) have improved the sensitivity of lateral flow immunoassay (LFIA). The preparation of immune probes in LFIA usually adopts the chemical coupling strategy with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide for antibody coupling, which has the problems of low coupling efficiency, tedious coupling process, and poor repeatability. A biocompatible metal-phenolic network (MPN), which contains large amounts of phenols and galloyl groups, could easily, quickly, and stably couple with antibodies...

Pesticide detection based on nanozyme is largely limited in terms of the variety of pesticides. Herein, a spherical and well-dispersed Fe3 O4 /graphene oxide nanoribbons (Fe3 O4 /GONRs) composite nanozyme was applied to firstly develop an enzyme-free and sensitive colorimetric and fluorescence dual-mode detection of thiophanate-methyl (TM). The synthesized Fe3 O4 /GONRs possess excellent dual enzyme-like activities (peroxidase and catalase) and can catalyze H2 O2 to oxidize 3,3',5,5'-tetramethylbenzidine (TMB) into oxidized TMB (oxTMB)...

This paper presents a high-precision CMOS fluorescence photometry sensor using a novel lock-in amplification scheme based on switched-biasing and ping-pong auto-zeroing techniques. The CMOS sensor includes two photodiodes and a lock-in amplifier (LIA) operating at 1 kHz. The LIA comprises a differential low-noise amplifier using a novel switched-biasing ping-pong auto-zeroed scheme, an automatic phase aligner, a programmable gain amplifier, a band-pass filter, a mixer, and an output low-pass filter. The design is fabricated in 0...

Folic acid (FA) is a water-soluble vitamin found in diverse natural sources and is crucial for preserving human health. The risk of health issues due to FA deficiency underscores the need for a straightforward and sensitive FA detection methodology. Carbon dots (CDs) have gained significant attention owing to their exceptional fluorescence performance, biocompatibility, and easy accessibility. Consequently, numerous research studies have concentrated on developing advanced CD fluorescent probes to enable swift and precise FA detection...

This study was based on the development of surface-based photoluminescence sensor for metal detection, quantification, and sample purification employing the solid sensory chip having the capability of metal entrapment. The Co(II), Cu(II) and Hg(II) sensitive fluorescence sensor (TP) was first synthesized and characterized its sensing abilities towards tested metal ions by using fluorescence spectral investigation while the synthesis and complexation of the receptor was confirmed by the chromogenic, optical, spectroscopic and spectrometric analysis...

For the first time, clemastine was estimated in this work utilizing two validated resonance Rayleigh scattering (RRS) and fluorimetric methods. The methods relied on forming an association complex in an acidic medium between eosin Y reagent and clemastine. In the spectrofluorimetric approach, the investigated drug was quantified by quenching the fluorescence-emission intensity of eosin Y at 543.5 nm. The RRS method relied on enhancing the RRS spectrum at 331.8 nm, which is produced when eosin Y interacts with clemastine...

Gizzerosine [2-amino-9-(4-imidazolyl)-7-azanonanoic acid] is a toxic amino acid formed from histamine and lysine at high temperatures, and may be present in foodstuffs (e.g., fishmeal and meat-bone meal) for animals including cats and dogs. Here we developed a simple, rapid, sensitive, specific, and automated method for the analysis of gizzerosine in foodstuffs by high-performance liquid chromatography (HPLC) involving pre-column derivatization with o-phthaldialdehyde (OPA) in the presence of N-acetylcysteine (instead of the usual 2-mercaptoethanol or ethanethiol reagent)...

Sleep deprivation (SD) is highly prevalent in the modern technological world. Emerging evidence shows that sleep deprivation is associated with oxidative stress. At the organelle level, the Golgi apparatus actively participates in the stress response. In this study, to determine whether SD and Golgi apparatus stress are correlated, we rationally designed and fabricated a novel Golgi apparatus-targeted ratiometric nanoprobe called Golgi dots for O2 ·- detection. This probe exhibits high sensitivity and selectivity in cells and brain slices of sleep-deprived mice...

Herein, a novel ratiometric sensor for fluorimetric and smartphone-assisted visual detection of Al3+ in environmental water was developed based on the target-regulated formation of Eu metal-organic frameworks (Eu MOFs). By employing 2-[4-(2-hydroxyethyl) piperazin-1-yl] ethanesulfonic acid (Hepes), Eu3+ and tetracycline (TC) as raw materials, Eu MOFs with red emission were facilely synthesized through the coordination of Eu3+ with Hepes and TC. However, upon the introduction of Al3+ , a higher affinity of TC towards Al3+ resulted in the formation of a TC-Al3+ complex with green fluorescence and inhibited the generation of Eu MOFs...

Viral infections are major causes of mortality in solid-organ and hematopoietic stem cell transplant recipients. Epstein-Barr virus (EBV) and Parvovirus B19 (B19V) are among the common viral infections after transplantation and were recommended for increased screening in relevant guidelines. Therefore, the development of rapid, specific, and cost-effective diagnostic methods for EBV and B19V is of paramount importance. We applied Fluorescence of Loop Primer Upon Self-Dequenching Loop-mediated Isothermal Amplification (FLOS-LAMP) for the first time to develop a novel multiplex assay for the detection of EBV and B19V; the fluorophore attached to the probe are self-quenched in unbound state...

The microviscosity of intracellular environments plays an important role in monitoring cellular function. Thus, the capability of detecting changes in viscosity can be utilized for the detection of different disease states. Viscosity-sensitive fluorescent molecular rotors are potentially excellent probes for these applications; however, the predictable relationships between chemical structural features and viscosity sensitivity are poorly understood. Here, we investigate a set of arylcyanoamide-based fluorescent probes and the effect of small aliphatic substituents on their viscosity sensitivity...

The ongoing multi-country outbreak of monkeypox virus (MPXV) has continuously attracted global attention, highlighting the critical need for timely and accurate methods to detect MPXV and differentiate its clades. Herein, we devised a novel multiplex ET-PCR (endonuclease restriction-mediated real-time PCR) assay that integrates PCR amplification, restriction endonuclease cleavage and real-time fluorescence detection to diagnose MPXV infection and distinguish the Congo Basin and West African MPXV strains. In the MPXV ET-PCR system, three sets of specific primers were designed for MPXV, Congo Basin and West African strains...

Immunochromatography (ICA) remains untapped toward enhanced sensitivity and applicability for fulfilling the nuts and bolts of on-site food safety surveillance. Herein, we report a fortified dual-spectral overlap with enhanced colorimetric/fluorescence dual-response ICA for on-site bimodal-type gentamicin (Gen) monitoring by employing polydopamine (PDA)-coated AuNPs (APDA) simultaneously serving as a colorimetric reporter and a fluorescence quencher. Availing of the enhanced colorimetric response that originated from the PDA layer, the resultant APDA exhibits less required antibody and immunoprobes in a single immunoassay, which facilitates improved antibody utilization efficiency and immuno-recognition in APDA-ICA...

Bio-templated luminescent noble metal nanoclusters (NCs) have attracted great attention for their intriguing physicochemical properties. Continuous efforts are being made to prepare NCs with high fluorescence quantum yield (QY), good biocompatibility, and tunable emission properties for their widespread practical applications as new-generation environment-friendly photoluminescent materials in materials chemistry and biological systems. Herein, we explored the unique photophysical properties of silver nanoclusters (AgNCs) templated by cytosine-rich customized hairpin DNA...

The exploration of our solar system to characterize the molecular organic inventory will enable the identification of potentially habitable regions and initiate the search for biosignatures of extraterrestrial life. However, it is challenging to perform the required high-resolution, high-sensitivity chemical analyses in space and in planetary environments. To address this challenge, we have developed a microfluidic organic analyzer (MOA) instrument that consists of a multilayer programmable microfluidic analyzer (PMA) for fluidic processing at the microliter scale coupled with a microfabricated glass capillary electrophoresis (CE) wafer for separation and analysis of the sample components...

Photoexcitation of a solute alters the solute-solvent interaction, resulting in the nonequilibrium relaxation of the solvation structure, often called a dynamic Stokes shift or solvation dynamics. Thanks to the local nature of the solute-solvent interaction, the characteristics of the local solvent environment dissolving the solute can be captured by the observation of this process. Recently, we derived the energy-represented Smoluchowski-Vlasov (ERSV) equation, a diffusion equation for molecular liquids, which can be used to analyze the solvation dynamics on the diffusion timescale...