Halobenzoquinone-mediated assembly of amino acid modified Mn-doped ZnS quantum dots for halobenzoquinones detection in drinking water

Publication date: 5 October 2018
Source:Analytica Chimica Acta, Volume 1026
Author(s): Zhe Jiao, Pengfei Zhang, Hongwei Chen, Jingwen Li, Zhengquan Zhong, Hongbo Fan, Faliang Cheng
Halobenzoquinones (HBQs) were reported as disinfection byproducts (DBPs) which had potential risk of bladder cancer. In this paper, a highly selective analytical method for HBQs was developed by HBQs-mediated assembly of amino acid modified Mn-doped ZnS/Quantum Dots (Mn: ZnS QDs). In the presence HBQs, a charge-transfer complex (CTC) was formed between aromatic rings of HBQs and the primary amino groups on the surface of the QDs. The formation of CTC led to the aggregation of QDs, as a result fluorescence decreasing occurred. The decrease was correlated with the concentration of HBQs. Then a fluorescence sensor array for discrimination of three kinds of HBQs including 2,6-Dichloro-1,4-benzoquinone (DCBQ), 2,6-Dibromo-1,4-benzoquinone (DBBQ) and 2,3,6-trichloro-1,4-benzoquinone (TCBQ) was developed. Four kinds of amino acids including cysteine, threonine, tyrosine and tryptophan were embellished on the Mn: ZnS QDs. The different extents of aggregation led to different fluorescence decreasing effect, thus distinct fluorescence patterns were created. It showed that three kinds of HBQs could be discriminated successfully by fluorescence sensor array at a range of concentrations through principal component analysis (PCA). The unknown samples were predicted by with a stepwise linear discriminant analysis (SLDA) using Mahalanobis distance as a selection criterion with accuracy of 100%. Remarkably, the practicability of the proposed sensor array was further validated by identification of three kinds of HBQs at different concentrations in real drinking water samples. Compared to LC/MS/MS, this fluorescent sensor array-based method was proved to be more convenient since the nanoparticles can be prepared flexibly according to the property of the target.

Graphical abstract

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Digital encoding based molecular imprinting suspension array for multiplexed label-free sensing of phenol derivatives

Publication date: 15 October 2018
Source:Sensors and Actuators B: Chemical, Volume 271
Author(s): Qinghua He, Tian Guan, Yonghong He, Bangrong Lu, Dongmei Li, Xuejing Chen, Guangxia Feng, Siyu Liu, Yanhong Ji, Meiguo Xin
A fluorescent suspension array combining digital encoding and molecular imprinting technologies was applied for multiplexed detection of phenols in aqueous medium. In this assay, nanomaterials such as silver (Ag), cuprous oxide (Cu2O), magnesium oxide (MgO), and zinc oxide (ZnO) were assembled on microbeads as digital encoding signal sources, then, (Digital encoding signal sources were produced by assembling silver (Ag), cuprous oxide Cu2O), magnesium oxide (MgO), and zinc oxide (ZnO) on microbeads. Molecular imprinted nanoparticles based on CdSe/ZnS quantum dots with various emission wavelengths (525, 565 and 585 nm) were grafted on the encoded beads through electrostatic adsorption and were used as the sensing units. The decoding spectra of the suspension array were stimulated and collected by a home-built laser induced breakdown spectroscopy system. The resulted spectra were transformed into digital sequences for encoding. As demonstrated in the gradient detections to various phenol solutions in concentration range of 0.98–62.5 μg/mL, the functionality of the suspension array was proven in the control experiments between the parent sensor beads and the molecular imprinting silica nanoparticles assembled sensor beads. Furthermore, the selectivity of suspension array was verified by the mixed adsorption experiments conducted in multicomponent analytes.



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Synthesis, structural characterization and photoluminescence property of two Zn2+/In3+-4,4′-oxydiphthalhydrazidate complexes

Publication date: 1 October 2018
Source:Inorganica Chimica Acta, Volume 482
Author(s): Juan Jin, Hou Chen, Xiao Zhang, Yu-Chang Wang, Zhen-Jiang Zhang, Qing-Feng Yang, Chen Lin, Ji-Rui Li, Qin-Jun Zhang
Under the hydrothermal conditions, two new 4,4′-oxydiphthalhydrazidate-containing compounds [Zn2(odpth)2(phen)2]·H2O 1 and [In(odpth)(ox)(phen)] 2 (odpth = 4,4′-oxydiphthalhydrazidate, phen = 1,10-phenanthroline, ox = oxalate), were obtained. Note that odpth ligand was derived from the hydrothermal in situ acylation reaction between 4,4′-oxydiphthalic acid (odpha) with N2H4⋅H2O. In compound 1, the odpth ligands exhibit a μ2-bridging mode, which link Zn(II) centers into a 1-D chained structure with ancillary phen molecules. Interestingly, in compound 2, the ox ligands exhibit a μ2-bridging mode, which link In(III) centers into a different 1-D chained structure with ancillary odpth and phen molecules. Although they are only 1-D chained coordination polymers, they all further self-assemble into the interesting supramolecular networks via π⋯π stacking or hydrogen-bonded interactions. The photoluminescence analyses indicate that the compounds in the different states (in the solid state or in aqueous solution) may exhibit different emission behaviors.

Graphical abstract

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Giant intrascrotal embryonal rhabdomyosarcoma in an adult: a case report and review of the literature

Intrascrotal embryonal rhabdomyosarcoma in adults is a rare tumor with high aggression and a poor prognosis. We report our patient's case and review the relevant literature to improve the understanding of this...

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Editorial Board

Publication date: June 2018
Source:European Annals of Otorhinolaryngology, Head and Neck Diseases, Volume 135, Issue 3





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Contents

Publication date: June 2018
Source:European Annals of Otorhinolaryngology, Head and Neck Diseases, Volume 135, Issue 3





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Laryngeal papillomatosis in Senegal: A ten-year experience

Publication date: June 2018
Source:European Annals of Otorhinolaryngology, Head and Neck Diseases, Volume 135, Issue 3
Author(s): S. Maïga, C. Ndiaye, M. Diouf, B.K. Diallo, M. Ndiaye, M.S. Diouf, I.C. Ndiaye, R. Diouf
ObjectivesThe objectives of this study were to describe the epidemiological, clinical and therapeutic characteristics of laryngeal papillomatosis in the Fann teaching hospital ENT department in Dakar, Senegal.Patients and methodsWe retrospectively reviewed all cases of laryngeal papillomatosis managed in the Fann teaching hospital ENT department between 1st January 2006 and 31st December 2015. Epidemiological, clinical and therapeutic characteristics of laryngeal papillomatosis were studied. Statistical analysis was performed with SPSS 18 software.ResultsThe median age at diagnosis was 11 years and the sex ratio was 1.88. The mean time to consultation was 4.5 years. The predominant symptom was dysphonia, present in all cases, followed by laryngeal dyspnoea in 64.6% of cases. The glottic area was involved in all patients. Tracheostomy was performed in 20.8% of cases. All patients in our study underwent endoscopic excision of the lesions.ConclusionLaryngeal papillomatosis is the most common benign tumor in children, but it can also occur in adults. Treatment has been revolutionized by progress in endoscopy and antiviral therapy. However, tracheostomy still occupies an important place in our practice.



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