Search

Herein, a dual-emission Eu metal-organic framework (Eu-MOF) is prepared and used as the ratiometric fluorescence probe for ultrasensitive detection of aminoglycoside antibiotics (AGs). Due to the strong hydrogen bond interactions between AGs and Eu-MOF, the blue emission is enhanced while the red emission has little fluctuation in Eu-MOF with the addition of AGs, thus a good linear relationship with the logarithm of AGs concentrations from 0.001 to 100 μg/mL can be established for quantitative analysis. Good sensitivity with the detection limit of 0.33 ng/mL for apramycin, 0.32 ng/mL for amikacin and 0.30 ng/mL for kanamycin is achieved. The proposed assay demonstrates good selectivity and applicability for determination of AGs in real milk and honey samples. The Eu-MOF materials are further fabricated as fluorescent test papers for facile visual detection. The as-established ratio fluorescence platform offers a portable and economical way for rapid monitoring AGs residues in complex food samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this study, naphthalene-modified magnetic nanoparticles (Fe 3 O 4 @Nap) were simply prepared based on specific chelation interaction between phosphate groups and metal ions on Fe 3 O 4 surface. The resultant Fe 3 O 4 @Nap were characterized by FTIR, BET, SEM, TEM, NAM, TGA, and VSM techniques. With Fe 3 O 4 @Nap as adsorbent, the polycyclic aromatic hydrocarbons (PAHs) were efficiently extracted by magnetic solid-phase extraction (MSPE) from environmental water and fish samples through the π-π interaction between modified naphthalene groups and PAHs, followed by their determination by GC-MS/MS. The key parameters influencing the extraction efficiency were investigated. Under the optimized conditions, the Fe 3 O 4 @Nap-based MSPE/GC-MS/MS method proposed in this paper was evaluated and applied for analyzing PAHs in environmental water and fish samples. And the proposed MSPE/GC-MS/MS method exhibited good linearities for water samples (in the range of 0.1-10 ng/mL, R 2 >0.9945) and for fish samples (in the range of 1-100 ng/g, R 2 > 0.9905). The limits of detection (LODs) for water and fish samples were 0.004-0.031 ng/mL and 0.07-0.28 ng/g, respectively. Additionally, this method exhibited desirable accuracy and precision. The PAH recovery values from water and fish samples ranged from 81.5% to 109.6% with inter- and intra-day relative standard deviations (RSDs) of less than 12.8%. The MSPE/GC-MS/MS method was successfully applied to the analysis of real environmental water and fish samples. Overall, the newly synthesized Fe 3 O 4 @Nap exhibited high sensitivity, specificity, reusability, repeatability, and it could efficiently extract PAHs from environmental water and fish samples by MSPE., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

In this work, a La 3+ assisted glutathione-capped gold nanoclusters and carbon dots (GSH-Au NCs/CDs) nanoplatform for sensitive detection of fenthion (FEN) is fabricated. The fluorescence response of GSH-Au NCs significantly increases due to aggregation-induced emission enhancement (AIEE) effect induced by La 3+ , which is further enhanced with adding FEN due to the coordination between La 3+ and FEN. Taking the fluorescence intensity of CDs as the signal background, the ratiometric fluorescence of GSH-Au NCs and CDs has a good linear relationship with the FEN concentration from 0.01 to 1.10 μg mL -1 , and detecting FEN exhibits a good sensitivity at a low detection limit of 6.74 ng g -1 . The La 3+ assisted GSH-Au NCs/CDs nanoplatform demonstrates desirable selectivity and applicability for monitoring trace level of FEN in fruit and vegetable samples. The non-enzymatic strategy by taking advantage of successive AIEE of GSH-Au NCs has a great potential for facile screening organophosphate pesticides in agro-products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In current study, a rapid and sensitive method for simultaneous determination of 8 phenoxy carboxylic acid (PCA) herbicides in environmental water samples was established based on an octyl and amino functionalized magnetic mesoporous silica (mOAS). The mOAS sorbent was fabricated by simple modification of octyl and aminopropyl groups onto the surface of magnetic mesoporous silica. Various techniques were employed to characterize the physical and chemical properties of the mOAS sorbent. The mOAS sorbent showed good extraction capacity and selectivity for PCA herbicides owing to the mixed-mode hydrophobic and ionic exchange interaction mechanisms. Then a one-factor-at-a-time approach was utilized for the optimization of extraction, washing and eluting conditions. Under the optimum conditions, wide linearity ranges with squared correlation coefficients ranging from 0.9888 to 0.9966 were obtained, and the method detection of limits (LODs) were in the range of 0.005-0.02 ng/mL. Furthermore, recoveries ranged from 86.9 to 114.6% with intra- and inter-day relative standard deviation (RSD) of 0.8-11.0% at three concentration levels spiked in blank water sample. Finally, the as-proposed method was successfully applied to extract 8 PCA herbicides in real water samples followed by determination with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Results showed that the mOAS as adsorbent for magnetic solid phase extraction (MSPE) of acidic herbicides is an efficient alternative with simplicity and rapidity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier B.V.)