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1.
Mikrochim Acta ; 190(7): 258, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37303021

RESUMO

Being a persuasive antibiotic, ciprofloxacin is widely administered to patients and its excessive discharge has generated a keen interest among researchers for its detection in water resources. Therefore, the current work utilizes the virtues of carbon dots synthesized from the leaves of Ocimum sanctum as an economical and convenient bimodal stratagem for the detection of ciprofloxacin via an electrochemical and fluorometric approach. The insight into photostability, size, morphology, and optical studies of the carbon dots was tested to enhance their scope in sensing. The excellent photoluminescence-based excitation-dependent behavior with a quantum yield of 46.7% and non-requirement of any kind of labeled surface variations for amending their fluorescence and electrochemical properties have further supported the utilization of as-prepared carbon dots in trace-level monitoring of ciprofloxacin. The fluorescence emission intensity and peak current were enhanced by many folds via the application of Ocimum sanctum-derived carbon dots. The synergetic effect of carbon dots has possessed a linear relationship between the peak current/emission intensity within the range of 0 to 250 µM of ciprofloxacin and the lowest detection limit value was found to be 0.293 and 0.0822 µM with fluorometric and electrochemical methods, respectively. The sensor demonstrated excellent applicability for the estimation of ciprofloxacin and acts as a high-performance dual sensor for further applications.


Assuntos
Anti-Infecciosos , Ciprofloxacina , Humanos , Ciprofloxacina/farmacologia , Antioxidantes , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Carbono
2.
Environ Res ; 212(Pt E): 113559, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35660407

RESUMO

The revolutionary growth in the usage of carbon quantum dots (CQDs) in different areas have ultimately directed their discharge in the environment and further augmented the exposure of agricultural crops to these released particles. Therefore, the aim of current study is to evaluate the uptake, translocation and phytotoxicity of blue emissive CQDs on Allium sativum plant. The genotoxicity and cytotoxicity assessment of CQDs towards Allium sativum roots was estimated as function of three different concentrations. Considering the role of CQDs in promoting seed germination at 50 ppm concentration, a greenhouse experiment was performed to evaluate their effect on plant growth. Systematic investigations have shown the translocation of CQDs and their physiological response in terms of increased shoot length wherein P-CQDs exhibited more accumulation into Allium sativum parts. Our investigations unfold the opportunity to utilize Aegle marmelos fruit derived CQDs as a growth regulator in variety of other food plants.


Assuntos
Alho , Pontos Quânticos , Carbono/toxicidade , Aberrações Cromossômicas/induzido quimicamente , Desenvolvimento Vegetal , Pontos Quânticos/toxicidade
3.
Molecules ; 27(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36014567

RESUMO

The transformation of biowaste into products with added value offers a lucrative role in nation-building. The current work describes the synthesis of highly water-soluble, luminous carbon quantum dots (CQDs) in the size range of 5-10 nm from discarded rice straw. The small spherical CQDs that were formed had outstanding optical and luminescent qualities as well as good photostabilities. By performing quantitative multi-assay tests that included antioxidant activities, in vitro stability and colloidal assay investigations as a function of different CQD concentrations, the biocompatibility of CQDs was evaluated. To clearly visualize the type of surface defects and emissive states in produced CQDs, excitation-dependent fluorescence emission experiments have also been carried out. The "waste-to-wealth" strategy that has been devised is a successful step toward the quick and accurate detection of Cu2+ ion in aqueous conditions. The fluorescence-quenching behavior has specified the concentration dependency of the developed sensor in the range of 50 µM to 10 nM, with detection limit value of 0.31 nM. The main advantage of the current research is that it offers a more environmentally friendly, economically viable and scaled-up synthesis of toxicologically screened CQDs for the quick fluorescence detection of Cu2+ ions and opens up new possibilities in wastewater management.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Íons , Luminescência , Água
4.
J Nanosci Nanotechnol ; 18(5): 3218-3229, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442822

RESUMO

This manuscript represents the synthesis of silica nanoparticles modified with four different types of cationic surfactants. The surfactant capped nanoparticles have better control over the size of silica nanoparticles. The as formed as model nanomaterials were used for the removal of naphthalene, a simple white crystalline polycyclic aromatic hydrocarbon (PAH) from aqueous media. The obtained materials were characterized by various microscopic and spectroscopic techniques. The average particle size of nanoparticles was approximately between 50 and 75 nm. The removal kinetic and adsorption studies were also conducted on silica nanoparticles with different contact time, initial concentrations of silica and naphthalene to achieve the optimum adsorption conditions. CPB functionalized nanoparticles have displayed higher removal efficiency of more than 85% as compared to 75 to 80% in case of CTAB, CTAC and CPC functionalized silica nanoparticles. The effects of various parameters like pH, adsorbent doses, naphthalene concentration and addition of salt have also been investigated for better understanding of the removal efficacy of prepared nanoparticles.

5.
J Environ Manage ; 228: 130-139, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30216827

RESUMO

The scarcity of available drinking water has led the researchers to develop novel and cost-effective ways of bioremediation process for wastewater treatment. Bioremediation is a cost-effective and environmentally sound method for the removal of toxic compounds. Such approach is not only a chemical-less effort but also an energy savior. In the present work Phlebia acerina, a white rot wood rotting fungi have been used to degrade the toxic wastewater pollutants. Congo Red (CR) and Eriochrome Black T (EBT) have been selected as model pollutants to test the wastewater cleaning ability of the fungus. The Lignin modifying enzyme (LME) and Cellulolytic enzyme assays (CMC) potential of Phlebia acerina helped in understanding the dye degradation mechanism. Under the optimum conditions, the fungi was able to degrade as high as 92.4% CR while the EBT was degraded to a maximum of 50%. Phlebia acerina was found to show first-order kinetics of dyes degradation. Further, the seed germination and antimicrobial assay of treated and untreated water were carried out in order to establish the formation of non-toxic end product after degradation.


Assuntos
Basidiomycota/metabolismo , Fungos/metabolismo , Compostos Azo , Biodegradação Ambiental , Corantes/metabolismo , Vermelho Congo , Poluentes Ambientais/metabolismo , Lignina/metabolismo , Águas Residuárias , Madeira/metabolismo
6.
Analyst ; 141(13): 4211-8, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27141553

RESUMO

The presence of heavy metal ions in the environment and in food items can severely harm human health. Thus, simple, reliable, sensitive, quick, and accurate methods for their detection must be developed as a means to improve healthcare worldwide. To this end, a robust method was developed for the direct sensing of arsenic(iii) in control and real environmental samples (at neutral pH) by a gold electrode that was modified with zirconia nanocubes synthesized via a facile hydrothermal route. This sensing system was used to build a sensing profile for arsenic ions after characterization of their elemental, optical, chemical, and morphological behavior. Electrochemical sensing of arsenic was achieved by cyclic voltammetry (CV) and chronoamperometry with an ultra-sensitivity of 550 nA cm(-2) ppb(-1) and a detection limit of 5 ppb (linear range of 5-60 ppb with a response time below 2 s). Although this system experienced small interference from Cd ions, the results of the real sample analysis were comparable to those of other standard techniques. The proposed method is advantageous and can be used to assess the toxicity of water, food, and other environmental samples without requiring any toxic solutions and/or gasses in any of the analytical steps. Moreover, due to its low price, portability, and easy mass production, it can be adopted for use in screen-printed electrodes.

7.
J Nanosci Nanotechnol ; 14(2): 1658-74, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24749448

RESUMO

This review provides insights into the synthesis, functionalization, and applications of selenium nanoparticles in electronics, optics, catalysis and sensors. The variation of physicochemical properties such as particle size, surface area, and shape of the selenium nanoparticles and the effect of experimental conditions has also been discussed. An overview has also been provided on the fundamental electrical and optical properties of selenium nanomaterials as well as their utilization in different research fields. The work presents an insight on selenium nanoparticles with interesting properties and their future applications.


Assuntos
Cristalização/métodos , Eletrônica/instrumentação , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Nanotecnologia/instrumentação , Selênio/química , Transdutores , Catálise , Condutividade Elétrica , Desenho de Equipamento , Tamanho da Partícula
8.
J Nanosci Nanotechnol ; 14(9): 6824-34, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924337

RESUMO

Nanotechnology's aptitude to silhouette matter at the scale of the nanometer has unlocked the flap to new inventions of applications in material science and nanomedicine. Engineered silica nanoparticles are key actor of this strategy. The amphitheatre of silica nanoparticles is inexplicably bilateral. Silica particles play essential function in everyday commercial purposes for instance energy storage, chemical and biological sensors, food processing and catalysis. One of the most appealing applications to emerge in the recent years is the use of silica particles for cleaning up contaminants in groundwater, soil and sediments. Herein this work, surfactant modified silica nanoparticles with unique surface and pore properties as well as high surface areas have been extensively investigated as an alternative for the dye removal. The physical and chemical characterizations of adsorbent have been studied using FTIR and scanning electron microscopy. The present investigation aims to explore the comparative effect of different surfactants during the formation of the target composite materials. The effects of various parameters like pH, adsorbent doses, dye concentration, addition of salt have also been investigated. These findings indicate that the nano silica particles are effective materials for dye removal and can be used to alleviate environmental problems.


Assuntos
Compostos Azo/química , Corantes/química , Nanopartículas/química , Dióxido de Silício/química , Tensoativos/química , Adsorção , Compostos Azo/isolamento & purificação , Corantes/isolamento & purificação , Recuperação e Remediação Ambiental , Nanotecnologia , Poluentes da Água
9.
Chemosphere ; 355: 141812, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554865

RESUMO

The bio-sensing activity of fluorescence based nanoprobes is one of the most significant aspects to scrutinize the analytical pursuance in modern security and lateral flow assays. Herein, potent transmogrification of waste cigarette tobacco into fluorescent carbon quantum dots (CQDs) has been achieved by calcination approach. The waste transformation to CQDs holds diverse benefits, comprising high quantum yield, low toxicity and scale up synthesis. The developed CQDs were able to identify tetracycline with phenomenal selectivity and sensitivity through fluorescence based method. The sensing mechanism was fully explored using Density Functional Theory (DFT) and Molecular docking studies. Governing features comprising tetracycline concentration, interfering studies, and real water analysis on the identification of tetracycline were also investigated. Along with, the prepared CQDs act as colorimetric probe, facilitating the detection of tetracycline with the naked eye. The lateral flow device was constructed for the on-site detection of tetracycline in real water samples. To the best of our knowledge, the present work represents a novel approach to designing CQDs and demonstrates their significant potential for application in anticounterfeiting measures and lateral flow devices. This work holds significant prospective as the prepared CQDs was fully utilized to its maximum usage in developing films and fluorescent anti-counterfeiting applications. Concisely, current work opens up distinctive opportunities for rapid on-site, real-time and visualized surveillance of tetracycline using CQDs prepared with a quite simple green approach.


Assuntos
Pontos Quânticos , Produtos do Tabaco , Carbono , Simulação de Acoplamento Molecular , Estudos Prospectivos , Tetraciclina , Corantes Fluorescentes , Antibacterianos , Água
10.
Chemosphere ; 357: 141935, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636909

RESUMO

The conversion of waste biomass into a value-added carbonaceous nanomaterial highlights the appealing power of biomass valorization. The advantages of using sustainable and cheap biomass precursors exhibit the tremendous opportunity for boosting energy production and their application in environmental remediation processes. This review emphasis the development and production of carbon-based nanomaterials derived from biomass, which possess favourable characteristics such as biocompatibility and photoluminescence. The advantages and limitations of various nanomaterials synthesised from different precursors were also discussed with insights into their physicochemical properties. The surface morphology of the porous nanomaterials is also explored along with their characteristic properties like regenerative nature, non-toxicity, ecofriendly nature, unique surface area, etc. The incorporation of various functional groups confers superiority of these materials, resulting in unique and advanced functional properties. Further, the use of these biomass derived nanomaterials was also explored in different applications like adsorption, photocatalysis and sensing of hazardous pollutants, etc. The challenges and outcomes obtained from different carbon-based nanomaterials are briefly outlined and discussed in this review.


Assuntos
Biomassa , Carbono , Recuperação e Remediação Ambiental , Nanoestruturas , Recuperação e Remediação Ambiental/métodos , Nanoestruturas/química , Carbono/química , Adsorção , Poluentes Ambientais/química , Catálise
11.
J Drugs Dermatol ; 12(10): 1149-53, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24085051

RESUMO

BACKGROUND: Various treatment modalities are available for management of melasma, ranging from topical and oral to chemical peeling, but none is promising alone. Very few studies are available regarding efficacy of combination of topical treatment with chemical peeling. Combination of chemical peeling and topical regimen can be a good treatment modality in the management of this recalcitrant disorder. OBJECTIVE: To assess the efficacy of combination of topical regimen (2% hydroquinone, 1% hydrocortisone and 0.05% tretinoin) with serial glycolic acid peeling in the treatment of melasma in Indian patients. METHODS: Forty Indian patients of moderate to severe epidermal variety melasma were divided into two groups of 20 each. One Group i.e. peel group received topical regimen (2% hydroquinone, 1% hydrocortisone and 0.05% tretinoin) with serial glycolic acid peeling and other group i.e. control group received topical regimen (2% hydroquinone, 1% hydrocortisone, 0.05% tretinoin). RESULTS: There was an overall decrease in MASI from baseline in 24 weeks of therapy in both the groups (P value < 0.05). The group receiving the glycolic acid peel with topical regimen showed early and greater improvement than the group which was receiving topical regimen only. CONCLUSION: This study concluded that combining topical regimen (2% hydroquinone, 1% hydrocortisone and 0.05% tretinoin) with serial glycolic acid peeling significantly enhances the therapeutic efficacy of glycolic acid peeling. The combination of glycolic acid peeling with the topical regimen is a highly effective, safe and promising therapeutic option in treatment of melasma.


Assuntos
Abrasão Química/métodos , Glicolatos/uso terapêutico , Melanose/tratamento farmacológico , Adulto , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Antioxidantes/efeitos adversos , Antioxidantes/uso terapêutico , Abrasão Química/efeitos adversos , Feminino , Glicolatos/administração & dosagem , Glicolatos/efeitos adversos , Humanos , Hidrocortisona/efeitos adversos , Hidrocortisona/uso terapêutico , Hidroquinonas/efeitos adversos , Hidroquinonas/uso terapêutico , Hiperpigmentação/induzido quimicamente , Hipertricose/induzido quimicamente , Irritantes , Ceratolíticos/efeitos adversos , Ceratolíticos/uso terapêutico , Masculino , Resultado do Tratamento , Tretinoína/efeitos adversos , Tretinoína/uso terapêutico , Adulto Jovem
12.
Chemosphere ; 340: 139823, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37586494

RESUMO

The highly biocompatible nature of carbon dots (CQDs) and potential usage in waste water treatment makes them as one of the effective alternative for treating water pollution. Herein, biogenic carbon dots (CQDs) with size range of 2 nm were prepared from waste coconut husk as a precursor source. The hydrophilic nature and higher surface area of as prepared CQDs has further supported the superior adsorption efficiency of more than 90% for Victoria blue B (VB) dye from waste water samples. Different dye adsorption parameters including adsorbate and adsorbent dosage, pH of reaction media and equilibrium time have been optimized and found that 8 mg of adsorbent was sufficient to remove 70 mg VB dye in 4 mL aqueous solution in 60 min at pH = 7. The adsorption kinetic (2nd order) and isotherms (Freundlich-type) were well followed on prepared CQDs. The reusability studies up to 5 times with minimal decrement of 4% confirm the constancy of CQDs for the adsorptive removal of VB. The methodology presents a greener way for overcoming ecological issues with sustainable materials in an economical manner.


Assuntos
Carbono , Poluentes Químicos da Água , Cocos , Corantes de Rosanilina , Adsorção , Cinética , Concentração de Íons de Hidrogênio
13.
Chemosphere ; 341: 139946, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37640216

RESUMO

A simpler and efficient method has been developed for the green synthesis of highly fluorescent carbon dots (CDs) from Azadirachta Indica leaves. The surface morphology of developed CDs has shown the existence of spherical particles in the size range of 3-8 nm with superior biocompatibility and high quantum yield value i.e. 42.3%. The particles exhibited a highly fluorescent and crystalline nature along with a bandgap value of 4.02 eV. The prepared CDs served as a factorial design for the sensing and degradation of Malachite green among other dyes. The main perspective of the current finding is that the designed catalyst exhibits excellent sensing results towards Malachite green with a limit of detection i.e. 0.144 µM in the concentration range of 0-50 µM. Moreover, the UV triggered results of photocatalysis illustrated a good dye removal efficacy by developed CDs with an average of 90.73, 98.25, 52 and 6.13% degradation in Methylene blue (MB), Malachite green (MG), Rhodamine 6G (Rh 6G) and Methyl orange (MO) upon 70 min of irradiation with mercury lamp. Additionally, the proton NMR, FTIR and FESEM results of the recycled samples also confirm the complete degradation of MG dye with the application of N-CDs.


Assuntos
Azadirachta , Pontos Quânticos , Pontos Quânticos/química , Carbono/química , Corantes/química , Corantes Fluorescentes/química
14.
ACS Appl Bio Mater ; 6(5): 1849-1862, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37076450

RESUMO

trans-1-(4'-Methoxyphenyl)-3-methoxy-4-phenyl 3-methoxyazetidin-2-one (or 3-methoxyazetidin-2-one) is one of the important ß-lactam derivatives with an ample range of bacterial activities yet few restrictions. To enhance the competency of the chosen 3-methoxyazetidin-2-one, microfibrils composed of copper oxide (CuO) and filter scraps of cigarette butts (CB) were chosen in the current work for developing a potential release formulation. The preparation of CuO-CB microfibrils required a simple reflux technique and a subsequent calcination treatment. The loading of 3-methoxyazetidin-2-one was processed via controlled magnetic stirring followed by centrifugation with microfibrils of CuO-CB. To confirm the loading efficiency, the 3-methoxyazetidin-2-one@CuO-CB complex was analyzed by scanning electron microscopy, transmission electron microscopy, and infrared spectroscopy. Compared to the CuO nanoparticles, the release profile of CuO-CB microfibrils indicates only 32% of the drug release in the first 1 h at pH 7.4. As a model organism, E. coli has been utilized for in vitro drug release dynamic studies. Based on the observed drug release data, it was found that the prepared formulation evades premature drug release and triggers the on-demand release of drug inside bacterial cells. The controlled drug release by 3-methoxyazetidin-2-one@CuO-CB microfibrils over a period of 12 h further ascertained the excellent bactericide delivery mechanism to combat deadly bacterial resistance. Indeed, this study provides a strategy to combat antimicrobial resistance and eradicate bacterial disease via nanotherapeutics.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Humanos , Nanopartículas Metálicas/química , Escherichia coli , Preparações de Ação Retardada/farmacologia , Composição de Medicamentos , Microfibrilas , Antibacterianos/farmacologia , Antibacterianos/química
15.
Sci Total Environ ; 872: 161960, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36739026

RESUMO

Nanostructured oxides and oxyhydroxides of iron are imperative constituents of the Earth's geological and biological processes i.e. biogeochemical cycles. So, the characteristic applications of iron oxide nanoparticles (FeONps) are closely linked to their surroundings and biological sinks. This work reports a low-cost green approach to promote 'waste-to-wealth' ideology by the direct and self-catalysis of iron rust into its nanoparticles (N-FeONps). A comparison is drawn based on the properties, morphologies, and applications after synthesizing FeONps by chemical precipitation method (C-FeONps). Spherical nanoparticles with vibrational properties are obtained in the size domain of 32 nm (N-FeONps) and 23 nm (C-FeONps). The application of Uniform deformation model, Uniform stress deformation model, Uniform deformation energy density model, and Size-strain plot models reveal comparatively greater defects in the crystal structures of C-FeONps. The biosafety profiling of natural and chemically designed nano-units performed on the species of bacteria, fungus, algae, and plants have shown enhanced safety terms associated with N-FeONps. The performance of N-FeONps has surpassed its chemical counterpart in medical applications such as antioxidant activity and anti-inflammatory activity with approximate percentages of 26 % and 51 % respectively. The findings of this piece of work favors the naturally obtained FeONps (N-FeONps), as they are economically viable, non-toxic, and have a greater antioxidant and anti-inflammatory arena. Hence, this waste-to-wealth ideology should be promoted for maintaining waste and designing solutions for the medical industries in one go.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Compostos Férricos/química , Monitoramento Biológico , Nanopartículas Metálicas/química , Ferro/química , Antioxidantes , Óxidos , Medição de Risco
16.
Nanomaterials (Basel) ; 13(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37110983

RESUMO

Herein, we have developed a one-pot methodology to synthesise three types of C-dots and their activated counterparts from three different types of waste plastic precursors such as poly-bags, cups and bottles. The optical studies have shown the significant change in the absorption edge in case of C-dots in comparison to their activated counterparts. The respective variation in the sizes is correlated with the change in electronic band gap values of formed particles. The changes in the luminescence behaviour are also correlated with transitions from the edge of the core of formed particles. The obtained variations in the Stokes shift values of C-dots, and their ACs were used to explore the types of surface states and their related transitions in particles. The mode of interaction between C-dots and their ACs was also determined using solvent-dependent fluorescence spectroscopy. This detailed investigation could provide significant insight on the emission behaviour and the potential usage of formed particles as an effective fluorescent probe in sensing applications.

17.
Viruses ; 15(10)2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37896846

RESUMO

Trialeurodes vaporariorum, commonly known as the greenhouse whitefly, severely infests important crops and serves as a vector for apple scar skin viroid (ASSVd). This vector-mediated transmission may cause the spread of infection to other herbaceous crops. For effective management of ASSVd, it is important to explore the whitefly's proteins, which interact with ASSVd RNA and are thereby involved in its transmission. In this study, it was found that a small heat shock protein (sHsp) from T. vaporariorum, which is expressed under stress, binds to ASSVd RNA. The sHsp gene is 606 bp in length and encodes for 202 amino acids, with a molecular weight of 22.98 kDa and an isoelectric point of 8.95. Intermolecular interaction was confirmed through in silico analysis, using electrophoretic mobility shift assays (EMSAs) and northwestern assays. The sHsp22.98 protein was found to exist in both monomeric and dimeric forms, and both forms showed strong binding to ASSVd RNA. To investigate the role of sHsp22.98 during ASSVd infection, transient silencing of sHsp22.98 was conducted, using a tobacco rattle virus (TRV)-based virus-induced gene silencing system. The sHsp22.98-silenced whiteflies showed an approximate 50% decrease in ASSVd transmission. These results suggest that sHsp22.98 from T. vaporariorum is associated with viroid RNA and plays a significant role in transmission.


Assuntos
Proteínas de Choque Térmico Pequenas , Hemípteros , Vírus de Plantas , Animais , Proteínas de Choque Térmico Pequenas/genética , Vírus de Plantas/genética , RNA , Hemípteros/genética
18.
Chem Asian J ; 18(23): e202300836, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37843415

RESUMO

The reactivity between bis(pyridin-2-yl)diselane o Py2 Se2 and ditellane o Py2 Te2 (L1 and L2, respectively; o Py=pyridyn-2-yl) and I2 /Br2 is discussed. Single-crystal structure analysis revealed that the reaction of L1 with I2 yielded [(HL1+ )(I- )⋅5/2I2 ]∞ (1) in which monoprotonated cations HL1+ template a self-assembled infinite pseudo-cubic polyiodide 3D-network, while the reaction with Br2 yielded the dibromide Ho PySeII Br2 (2). The oxidation of L2 with I2 and Br2 yielded the compounds Ho PyTeII I2 (3) and Ho PyTeIV Br4 (6), respectively, whose structures were elucidated by X-ray diffraction analysis. FT-Raman spectroscopy measurements are consistent with a 3c-4e description of all the X-Ch-X three-body systems (Ch=Se, Te; X=Br, I) in compounds 2, 3, Ho PyTeII Br2 (5), and 6. The structural and spectroscopic observations are supported by extensive theoretical calculations carried out at the DFT level that were employed to study the electronic structure of the investigated compounds, the thermodynamic aspects of their formation, and the role of noncovalent σ-hole halogen and chalcogen bonds in the X⋅⋅⋅X, X⋅⋅⋅Ch and Ch⋅⋅⋅Ch interactions evidenced structurally.

19.
Dermatol Online J ; 18(8): 7, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22948057

RESUMO

Brooke-Spiegler syndrome is an uncommon disease. Patients have a predisposition to develop cutaneous adnexal neoplasms such as cylindromas, trichoepitheliomas, spiradenomas, trichoblastomas, basal cell carcinomas, follicular cysts, and organoid nevi. Malignant transformation of preexisting tumors also occurs in these individuals. Various techniques have been used for the treatment of trichoepitheliomas and cylindromas including excision, electrocautery, carbon dioxide laser ablation, cryosurgery, and radiotherapy. In our case, cylindromas were ablated by radiofrequency in multiple sittings. Trichoepitheliomas were ablated using coagulation mode with power # 3 to 3.5. Cosmetically acceptable results were obtained in 100 percent of the cylindromas and 70 percent of the trichoepitheliomas (Visual Analog Scale). The radiofrequency ablation technique under different modes can be used in both large tumors as well as smaller ones, especially in developing countries because it is very cost effective and easily accessible.


Assuntos
Técnicas de Ablação/métodos , Carcinoma Adenoide Cístico/cirurgia , Síndromes Neoplásicas Hereditárias/cirurgia , Neoplasias Cutâneas/cirurgia , Técnicas de Ablação/economia , Carcinoma Adenoide Cístico/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Neoplásicas Hereditárias/patologia , Neoplasias Cutâneas/patologia , Resultado do Tratamento
20.
Food Chem ; 373(Pt B): 131492, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34743055

RESUMO

Herein a simple strategy has been demonstrated for the synthesis of environmentally amiable and highly fluorescent carbon dots from the most useful plant of Indian classical Ayurveda i.e. Bael patra fruit. The morphological features and chemical composition of the prepared carbon dots were characterized through High resolution transmission electron microscopy, Field emission scanning electron microscopy and X-ray photoelectron spectroscopy. Owing to their highly emission nature, the applicability of carbon dots was tested against various food colorant i.e. Allura red. Under the optimized conditions, the decreased fluorescence intensity exhibited a good linear relationship with increasing concentration of Allura red. Additionally, an extensive research was carried out to determine the adsorption efficiency of carbon dots for Allura red and heavy metals. Based on the context, here we report the novelty of this work, demonstrating the decontamination of various samples from Allura red and heavy metals with the application of carbon dots.


Assuntos
Corantes de Alimentos , Metais Pesados , Pontos Quânticos , Carbono , Corantes Fluorescentes
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