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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124290, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38669984

RESUMO

Hydrogen Peroxide (H2O2) is a highly hazardous, toxic, and carcinogenic chemical compound utilised in various industries-based applications. Despite strict restriction, they are deliberately added to food items such as milk as preservatives to increase its shelf life. Herein, we have formulated a green rapid colorimetric nanosensor for detection of H2O2 in milk using cotton leaves as both reducing and functionalizing agent for synthesis of silver nanoparticles (AgNPs). UV-Vis spectra exhibit a strong plasmonic peak at around 434 nm. X-Ray Diffraction (XRD) analysis was performed to determine the crystallinity of the nanoparticles. Field Emission Scanning Electron Microscope (FESEM) and Transmission Electron Microscope (TEM) characterizations revealed spherical morphology with size approximately âˆ¼16 nm. This functionalized nanoparticle could colorimetrically sense presence of H2O2 in milk samples both in liquid media and on paper substrates with Limit of Detection (LOD) of 8.46 ppm even in presence of other interfering substances in milk. This inexpensive route will pave the way for in depth research.


Assuntos
Colorimetria , Peróxido de Hidrogênio , Limite de Detecção , Nanopartículas Metálicas , Leite , Papel , Prata , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Leite/química , Colorimetria/métodos , Animais , Prata/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Espectrofotometria Ultravioleta
2.
Polymers (Basel) ; 16(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38257018

RESUMO

Resistive switching memories are among the emerging next-generation technologies that are possible candidates for in-memory and neuromorphic computing. In this report, resistive memory-switching behavior in solution-processed trans, trans-1,4-bis-(2-(2-naphthyl)-2-(butoxycarbonyl)-vinyl) benzene-PVA-composite-based aryl acrylate on an ITO-coated PET device was studied. A sandwich configuration was selected, with silver (Ag) serving as a top contact and trans, trans-1,4-bis-(2-(2-naphthyl)-2-(butoxycarbonyl)-vinyl) benzene-PVA-composite-based aryl acrylate and ITO-PET serving as a bottom contact. The current-voltage (I-V) characteristics showed hysteresis behavior and non-zero crossing owing to voltages sweeping from positive to negative and vice versa. The results showed non-zero crossing in the devices' current-voltage (I-V) characteristics due to the nanobattery effect or resistance, capacitive, and inductive effects. The device also displayed a negative differential resistance (NDR) effect. Non-volatile storage was feasible with non-zero crossing due to the exhibition of resistive switching behavior. The sweeping range was -10 V to +10 V. These devices had two distinct states: 'ON' and 'OFF'. The ON/OFF ratios of the devices were 14 and 100 under stable operating conditions. The open-circuit voltages (Voc) and short-circuit currents (Isc) corresponding to memristor operation were explained. The DC endurance was stable. Ohmic conduction and direct tunneling mechanisms with traps explained the charge transport model governing the resistive switching behavior. This work gives insight into data storage in terms of a new conception of electronic devices based on facile and low-temperature processed material composites for emerging computational devices.

3.
Pharmaceutics ; 15(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36678908

RESUMO

Cancer is one of the dreaded diseases to which a sizeable proportion of the population succumbs every year. Despite the tremendous growth of the health sector, spanning diagnostics to treatment, early diagnosis is still in its infancy. In this regard, circulating tumour cells (CTCs) have of late grabbed the attention of researchers in the detection of metastasis and there has been a huge surge in the surrounding research activities. Acting as a biomarker, CTCs prove beneficial in a variety of aspects. Nanomaterial-based strategies have been devised to have a tremendous impact on the early and rapid examination of tumor cells. This review provides a panoramic overview of the different nanotechnological methodologies employed along with the pharmaceutical purview of cancer. Initiating from fundamentals, the recent nanotechnological developments toward the detection, isolation, and analysis of CTCs are comprehensively delineated. The review also includes state-of-the-art implementations of nanotechnological advances in the enumeration of CTCs, along with future challenges and recommendations thereof.

4.
Fish Shellfish Immunol ; 110: 116-126, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33453382

RESUMO

A vast range of research related to the toxicity of the heavy metal cadmium (Cd) has been carried out in a wide variety of fish species. However, Cd induced immunomodulation in monocytes/macrophages of Channa punctatus Bloch. has rarely been explored. The present study was designed to determine Cd induced immune response, role of NF-κB (nuclear factor kappa B) pathway and the subsequent downstream molecular responses in monocytes/macrophages of C. punctatus. Fish were sampled and acclimatized, with one group treated with cadmium chloride (CdCl2) (1.96 mg/L) and another kept as untreated control group, both under observation for 7 days. Exposure to CdCl2 was found to alter hematological profile of C. punctatus in addition to incurring histo-architectural damages in the HK (head kidney) and ultrastructural changes in the monocytes/macrophages. The innate immune potential was found to be significantly compromised as evident from decreased phagocytosis, intracellular killing, cell adhesion and reduced release of nitric oxide (NO) and myeloperoxidase (MPO) in Cd intoxicated group. Also Cd triggered ROS generation, reduced cellular NO levels by forming peroxynitrite along with the upregulated expression of the inflammatory marker iNOS (inducible nitric oxide synthase) in monocytes/macrophages, both at mRNA and protein levels, indicating inflammation. Inflammation is further verified from the upregulated expression of proinflammatory cytokines viz. TNF-α, IL-1ß, IL-6, IL-12 along with a central inflammatory mediator NF-κΒ and downregulation of the anti-inflammatory cytokine IL-10, both at mRNA and protein levels. It can be concluded that, a sub-lethal exposure of Cd in C. punctatus for 7 days caused significant alterations in the hematological, histological and ultrastructural profile in monocytes/macrophages; impaired innate immune parameters, triggers ROS generation and inflammation as validated from the upregulated expression of NF-κΒ, iNOS, TNF-α, IL-1ß, IL-6, IL-12 and IL-10 downregulation.


Assuntos
Cádmio/efeitos adversos , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Peixes , Regulação da Expressão Gênica/imunologia , Inflamação/veterinária , Poluentes Químicos da Água/efeitos adversos , Animais , Doenças dos Peixes/induzido quimicamente , Inflamação/induzido quimicamente , Inflamação/imunologia , Macrófagos/imunologia , Monócitos/imunologia , NF-kappa B/imunologia , Transdução de Sinais/imunologia
5.
J Chem Phys ; 134(3): 035101, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21261390

RESUMO

The catalytic conversion of adenosine triphosphate (ATP) and adenosine monophosphate (AMP) to adenosine diphosphate (ADP) by adenylate kinase (ADK) involves large amplitude, ligand induced domain motions, involving the opening and the closing of ATP binding domain (LID) and AMP binding domain (NMP) domains, during the repeated catalytic cycle. We discover and analyze an interesting dynamical coupling between the motion of the two domains during the opening, using large scale atomistic molecular dynamics trajectory analysis, covariance analysis, and multidimensional free energy calculations with explicit water. Initially, the LID domain must open by a certain amount before the NMP domain can begin to open. Dynamical correlation map shows interesting cross-peak between LID and NMP domain which suggests the presence of correlated motion between them. This is also reflected in our calculated two-dimensional free energy surface contour diagram which has an interesting elliptic shape, revealing a strong correlation between the opening of the LID domain and that of the NMP domain. Our free energy surface of the LID domain motion is rugged due to interaction with water and the signature of ruggedness is evident in the observed root mean square deviation variation and its fluctuation time correlation functions. We develop a correlated dynamical disorder-type theoretical model to explain the observed dynamic coupling between the motion of the two domains in ADK. Our model correctly reproduces several features of the cross-correlation observed in simulations.


Assuntos
Difosfato de Adenosina/química , Monofosfato de Adenosina/química , Adenosina Trifosfatases/química , Adenilato Quinase/metabolismo , Simulação de Dinâmica Molecular , Movimento (Física) , Adenilato Quinase/química , Biocatálise , Modelos Moleculares , Estrutura Terciária de Proteína
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