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1.
Analyst ; 148(11): 2582-2593, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37159231

RESUMO

Diethyl cyanophosphonate (DCNP), a simulant of Tabun, is a common pollutant in pharmaceutical waste and poses a high risk to living organisms. Herein, we demonstrate a compartmental ligand-derived trinuclear zinc(II) cluster [Zn3(LH)2(CH3COO)2] as a probe for the selective detection and degradation of DCNP. It consists of two pentacoordinated Zn(II) [4.4.3.01,5]tridecane cages bridged through a hexacoordinated Zn(II) acetate unit. The structure of the cluster has been elucidated by spectrometric, spectroscopic, and single-crystal X-ray diffraction studies. The cluster shows a two-fold increased emission as compared to the compartmental ligand (at λexc = 370 nm and λem = 463 nm) due to the chelation-enhanced fluorescence effect and acts as a turn-off signal in the presence of DCNP. It can detect DCNP at nano levels up to 186 nM (LOD). The direct bond formation between DCNP and Zn(II) via the -CN group degrades it to inorganic phosphates. The mechanism of the interaction and degradation is supported by spectrofluorimetric experiments, NMR titration (1H and 31P), time of flight mass spectrometry and density functional theory calculations. The applicability of the probe has been further tested by the bio-imaging of zebrafish larvae, analysis of high-protein food products (meat and fish) and vapour phase detection by paper strips.


Assuntos
Substâncias para a Guerra Química , Animais , Substâncias para a Guerra Química/análise , Zinco/análise , Peixe-Zebra , Ligantes , Preparações Farmacêuticas
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 294: 122521, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-36842208

RESUMO

The distinction in coordination modes of metal complexes leads to their versatile structural features and unique properties. Here, we report two tetradentate Schiff base ligands (H2L1 and H2L2) bearing N2O2 donor sets, tactically selected to provide distinct coordination modes with different metal ions. The ligands were utilized to synthesize their organotin(IV) (1-4) and vanadium(V) (5) derivatives. The synthesized compounds were characterized using elemental analysis, FT-IR spectroscopy, multi-nuclei NMR (1H, 13C, and 119Sn) spectroscopy, mass spectrometry, and single-crystal X-ray diffraction. The organotin(IV) derivatives (1-4) displayed hepta-coordination around both the Sn centres as they were achieved in their dimeric form. Contrariwise, the vanadium(V) compound (5) was isolated as a mononuclear entity exhibiting penta-coordinated geometry around the vanadium centre. The variation in the coordination modes was evident in their UV-vis and fluorescence spectra. The organotin(IV) compounds (1-4) exhibited a strong emission band centred at 468 nm when excited at a wavelength of 360 nm whereas the vanadium(V) (5) derivative displayed poor fluorogenic response. Compound 1 was further explored for the fluorogenic chemo-sensing of permanganate ions (MnO4-) amongst various anions by quenching response. A detailed investigation of the recognition of permanganate ions was accomplished by spectrofluorometric, spectroscopic (119Sn NMR), mass spectrometric, and computational studies.

3.
Chemosphere ; 297: 134122, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35257701

RESUMO

The nanostructured, inner-coupled Bismuth oxyhalides (BiOX0.5X'0.5; X, X' = Cl, Br, I; X≠X') heterostructures were prepared using Quercetin (Q) as a sensitizer. The present study revealed the tuning of the band properties of as-prepared catalysts. The catalysts were characterized using various characterization techniques for evaluating the superior photocatalytic efficiency and a better understanding of elemental interactions at interfaces formed in the heterojunction. The material (BiOCl0.5Br0.5-Q) reflected higher degradation of MO (about 99.85%) and BPA (98.34%) under visible light irradiation than BiOCl0.5I0.5-Q and BiOBr0.5I0.5-Q. A total of 90.45 percent of total organic carbon in BPA was removed after visible light irradiation on BiOCl0.5Br0.5-Q. The many-fold increase in activity is attributed to the formation of multiple interfaces between halides, conjugated π-electrons and multiple -OH groups of quercetin (Q). The boost in degradation efficiency can be attributed to the higher surface area, 2-D nanostructure, inhibited electron-hole recombination, and appropriate band-gap of the heterostructure. Photo-response of BiOCl0.5Br0.5-Q is higher compared to BiOCl0.5I0.5-Q and BiOBr0.5I0.5-Q, indicating better light absorption properties and charge separation efficiency in BiOCl0.5Br0.5-Q due to band edge position. First-principles Density Functional Theory (DFT) based calculations have also provided an insightful understanding of the interface formation, physical mechanism, and superior photocatalytic performance of BiOCl0.5Br0.5-Q heterostructure over other samples.


Assuntos
Luz , Quercetina , Catálise
4.
J Family Med Prim Care ; 3(4): 404-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25657953

RESUMO

BACKGROUND AND OBJECTIVES: Obesity and overweight is a growing pandemic affecting millions of adolescents in developed as well as developing countries. Obesity is associated with the onset of major chronic diseases leading to complications and also psychosocial problems in adolescents. The greater concern is that the risks of obesity during childhood will persist into adolescence and adulthood. The objectives of the study were to assess the prevalence of being overweight and obesity and to study the associated risk factors. MATERIALS AND METHODS: 1900 adolescents in the age group of 10-19 years were included in the study. A predesigned and pretested questionnaire which included the variables such as going to school by bus or cycle, eating habits, playing video/computer games or outdoor games and sibling count were recorded. Body weight and height were recorded in subjects for calculating body mass index (BMI). International Obesity Task Force (IOTF) classification was used for the estimation of being overweight and obese. RESULTS: The mean age of the study subjects was 14.84 years (SD = 2.81). Mean weight increased from 34.7 to 55.09 kg from the age group 10-13 to 17-19 years. Mean height also increased from 1.34 to 1.57 m from the age group 10-13 to 17-19 years. Similarly, the mean body mass index was 19.23 at 10-13 years, followed by 21.11 at 14-16 years and 22.46 at 17-19 years. On binary logistic regression analysis, female gender, bus as a mode of transport, not playing games, and single sibling were found to have independent association with prevalence of being overweight.

5.
Artigo em Inglês | IMSEAR | ID: sea-165541

RESUMO

Median nerve is formed by union of lateral and medial roots arising from the corresponding cords of the brachial plexus. Ulnar nerve arises from the medial cord of brachial plexus itself. Only few communications between the median and ulnar nerve have been reported and described in the available literature. During routine dissection of the upper limb of a male cadaver for teaching undergraduate medical students, a variation was observed in the course of median nerve and ulnar nerve communications in palm. A very rare communication was found in which there is superficial and deep communication between ulnar and median nerve was observed only in one male cadaver (1.25%). This type of communication was not found in any other cadaver so far. This dual ansa formation between branches of ulnar and median nerve by communicating branches at superficial and deep levels in palm is rare to observe in which there is co-existence of Berretini Communications and Riche-Cannieu Communications is found in one hand only.

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