The synthesis of Cu nanoclusters and their dual mode colorimetric and fluorescent sensing for 2,4-dinitrophenol.

Herein, we have reported a facile one-pot strategy to synthesize fluorescent Cu nanclusters (Cu NCs) by using ʟ-histidine as stabilizer, and ascorbic acid as reducing agent. Cu NCs are stable, water-dispersible, and emit bright cyan emission with a quantum yield 26.08%. The Cu NCs can be employed as colorimetric and fluorimetric dual-mode detector, exhibiting excellent selectivity and sensitivity for detecting 2,4-dinitrophenol (DNP) specifically. Notably, Cu NCs were a sensitive sensor, which had speciality to detect DNP in range of linearity from 0.01 to 0.15 mM with a discernable limit as low as 3.96µM. The mechanism of efficiently selective detection of DNP by Cu NCs was analyzed by UV absorption, fluorescence decay spectrum, and the performance of 'turn off' towards DNP was determined as the inner filter effect and static quenching effect. Further, the environmental tolerance of the Cu NCs probe was estimated by using the different natural water samples, demonstrating its great promise in the field of DNP monitoring and water sample analysis.

Fluorescent silicon nanoparticles as dually emissive probes for copper(II) and for visualization of latent fingerprints.

The work describes dually-emissive silicon nanoparticles (Si NPs) in aqueous dispersion with two emissions. The Si NPs respond to different solvents independently with various wavelength fluorescence emissions (red to green). The fluorescence emission wavelengths and emissive color of Si NPs can be regulated by adjustment of the solvents. Based on the effect of the solvent, a series different emission color Si NPs is obtained (Si NPs A, B, C and D), which exhibit different fluorescence emission in various solvents. Notably, the Si NP-A (dispersed in water) exhibited excellent analytical performance in sensing Cu2+ ions with amazing fluorescent response from green to brilliant blue light. The much more enhancement at 436 nm than at 500 nm was due to the changing surface chemistry of Si NPs by Cu2+, which was dependent to the concentration of Cu2+ tightly. The excellent sensitivity of Si NP-A towards Cu2+ has been testified with the detection limit as low as 0.91 µM by good linear relationship between ratio of fluorescence intensity (I436/I500) and concentration of Cu2+ (2-30 µM). The Si NP-A can be exploited as a dual-fluorescence visualization agent for latent fingerprints imaging due to the feature of dual emission. The images exhibited green emission under excited at 254 nm, and emerged green light under 365 nm, which allowed the Si NP-A applying in development of latent finger prints at complex background. These acquired fingerprints revealed the particular second-level characteristics. Graphical abstractIllustration of the method for preparation of safranine-dyes silica nanoparticle (Si NPs), the evolution of Si NP-A (VSi NPs/Vwate = 1:2). Si NP-B (VSi NPs/Vdichloromethane = 1:1), Si NP-C (VSi NPs/Vethyl acetate = 1:1) and Si NP-D (VSi NPs/Vacetone = 1:1), and the application of water-dispersed silica nanoparticles (Si NP-A) to the detection and visualization of latent fingerprints (LFPs).

HCMMD: systematic evaluation of metabolites in body fluids as liquid biopsy biomarker for human cancers.

Metabolomics is a rapidly expanding field in systems biology used to measure alterations of metabolites and identify metabolic biomarkers in response to disease processes. The discovery of metabolic biomarkers can improve early diagnosis, prognostic prediction, and therapeutic intervention for cancers. However, there are currently no databases that provide a comprehensive evaluation of the relationship between metabolites and cancer processes. In this review, we summarize reported metabolites in body fluids across pan-cancers and characterize their clinical applications in liquid biopsy. We conducted a search for metabolic biomarkers using the keywords ("metabolomics" OR "metabolite") AND "cancer" in PubMed. Of the 22,254 articles retrieved, 792 were deemed potentially relevant for further review. Ultimately, we included data from 573,300 samples and 17,083 metabolic biomarkers. We collected information on cancer types, sample size, the human metabolome database (HMDB) ID, metabolic pathway, area under the curve (AUC), sensitivity and specificity of metabolites, sample source, detection method, and clinical features were collected. Finally, we developed a user-friendly online database, the Human Cancer Metabolic Markers Database (HCMMD), which allows users to query, browse, and download metabolite information. In conclusion, HCMMD provides an important resource to assist researchers in reviewing metabolic biomarkers for diagnosis and progression of cancers.

Carbon dots-magnetic nanocomposites for the detection and removal of Hg2.

The dual functional detection and removal of heavy ion metals by carbon dots has become an urgent matter of concern. Here, a unique fluorescent carbon dot-magnetic nanocomposite (Fe3O4/CDs) was prepared by hydrothermal methods for sensitive detection of Hg2+. The Fe3O4/CDs serve as fluorescent probes with higher selectivity and sensitivity for Hg2+, with the lowest detectable limit of 0.3 nM. Hg2+ statically quenched the blue emission of Fe3O4/CDs, which can be restored in the presence of saturated EDTA solution. The utilization of Fe3O4/CDs was fulfilled by recovering their emission conveniently. The recovery of Hg2+ in Chagan Lake water, tap water and drinks was calculated at 96.5 ~ 108.8%, which demonstrates the feasibility of the Fe3O4/CDs sensing system in natural samples. Notably, the Fe3O4/CDs can drive the effective removal of Hg2+ from samples, which is of outstanding significance as a promising probe in environmental monitoring.