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1.
Adv Colloid Interface Sci ; 331: 103245, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38945073

RESUMEN

Quantum dots (QDs), a novel category of semiconductor materials, exhibit extraordinary capabilities in tuning optical characteristics. Their emergence in biophotonics has been noteworthy, particularly in bio-imaging, biosensing, and theranostics applications. Although conventional QDs such as PbS, CdSe, CdS, and HgTe have garnered attention for their promising features, the presence of heavy metals in these QDs poses significant challenges for biological use. To address these concerns, the development of Ag chalcogenide QDs has gained prominence owing to their near-infrared emission and exceptionally low toxicity, rendering them suitable for biological applications. This review explores recent advancements in Ag chalcogenide QDs, focusing on their synthesis methodologies, surface chemistry modifications, and wide-ranging applications in biomedicine. Additionally, it identifies future directions in material science, highlighting the potential of these innovative QDs in revolutionizing the field.

2.
J Colloid Interface Sci ; 660: 412-422, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38244507

RESUMEN

Monkeypox is a zoonotic viral infection caused by the monkeypox virus (MPXV), which belongs to the Poxviridae family of the Orthopoxvirus (OPXV) genus. Monkeypox is transmitted from animals to humans and humans to humans; therefore, the accurate and early detection of MPXV is crucial for reducing mortality. A novel graphene-based material, graphene quantum rods (GQRs) was synthesized and confirmed using high-resolution transmission electron microscopy (HR-TEM) and atomic force microscopy (AFM). In this study, molybdenum oxide was electrodeposited and one-pot electrodeposition of MoO3-GQRs composite on carbon fiber paper (CFP) enabled by an antibody (Ab A29)/MoO3-GQRs immunoprobe was developed for the early diagnosis of MPXV protein (A29P). Several studies were conducted to analyze the MoO3-GQRs composite, and the prepared Ab A29/MoO3-GQRs immunoprobe selectively bound to the A29P antigen that was measured using differential pulse voltammetry (DPV) analysis and impedance spectroscopy. The antigen-antibody interaction was analyzed using X-ray photoelectron spectroscopy. DPV analysis showed a wide linear range of detection from 0.5 nM to 1000 nM, a detection limit of 0.52 nM, and a sensitivity of 4.51 µA in PBS. The prepared immunoprobe was used to analyze A29P in serum samples without reducing electrode sensitivity. This system is promising for the clinical analysis of A29P antigen and offers several advantages, including cost-effectiveness, ease of use, accuracy, and high sensitivity.


Asunto(s)
Grafito , Mpox , Animales , Humanos , Grafito/química , Monkeypox virus , Molibdeno/química
3.
Small ; 20(1): e2305289, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37649146

RESUMEN

Green fuel from water splitting is hardcore for future generations, and the limited source of fresh water (<1%) is a bottleneck. Seawater cannot be used directly as a feedstock in current electrolyzer techniques. Until now single atom catalysts were reported by many synthetic strategies using notorious chemicals and harsh conditions. A cobalt single-atom (CoSA) intruding cobalt oxide ultrasmall nanoparticle (Co3 O4 USNP)-intercalated porous carbon (PC) (CoSA-Co3 O4 @PC) electrocatalyst was synthesized from the waste orange peel as a single feedstock (solvent/template). The extended X-ray absorption fine structure spectroscopy (EXAFS) and theoretical fitting reveal a clear picture of the coordination environment of the CoSA sites (CoSA-Co3 O4 and CoSA-N4 in PC). To impede the direct seawater corrosion and chlorine evolution the seawater has been desalinated (Dseawater) with minimal cost and the obtained PC is used as an adsorbent in this process. CoSA-Co3 O4 @PC shows high oxygen evolution reaction (OER) activity in transitional metal impurity-free (TMIF) 1 M KOH and alkaline Dseawater. CoSA-Co3 O4 @PC exhibits mass activity that is 15 times higher than the commercial RuO2 . Theoretical interpretations suggest that the optimized CoSA sites in Co3 O4 USNPs reduce the energy barrier for alkaline water dissociation and simultaneously trigger an excellent OER followed by an adsorbate evolution mechanism (AEM).

4.
Biosensors (Basel) ; 13(12)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38131768

RESUMEN

Neurotransmitters (NTs) are endogenous low-molecular-weight chemical compounds that transmit synaptic signals in the central nervous system. These NTs play a crucial role in facilitating signal communication, motor control, and processes related to memory and learning. Abnormalities in the levels of NTs lead to chronic mental health disorders and heart diseases. Therefore, detecting imbalances in the levels of NTs is important for diagnosing early stages of diseases associated with NTs. Sensing technologies detect NTs rapidly, specifically, and selectively, overcoming the limitations of conventional diagnostic methods. In this review, we focus on the fluorescence-based biosensors that use nanomaterials such as metal clusters, carbon dots, and quantum dots. Additionally, we review biomaterial-based, including aptamer- and enzyme-based, and genetically encoded biosensors. Furthermore, we elaborate on the fluorescence mechanisms, including fluorescence resonance energy transfer, photon-induced electron transfer, intramolecular charge transfer, and excited-state intramolecular proton transfer, in the context of their applications for the detection of NTs. We also discuss the significance of NTs in human physiological functions, address the current challenges in designing fluorescence-based biosensors for the detection of NTs, and explore their future development.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , Puntos Cuánticos , Humanos , Técnicas Biosensibles/métodos , Puntos Cuánticos/química , Nanoestructuras/química , Carbono , Neurotransmisores
5.
J Funct Biomater ; 14(8)2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37623670

RESUMEN

Nanomaterials (NMs) synthesized from natural sources have been attracting greater attention, due to their intrinsic advantages including biocompatibility, stimuli-responsive property, nontoxicity, cost-effectiveness, and non-immunogenic characteristics in the biological environment. Among various biomedical applications, a breakthrough has been achieved in the development of drug delivery systems (DDS). Biocompatibility is necessary for treating a disease safely without any adverse effects. Some components in DDS respond to the physiological environment, such as pH, temperature, and functional group at the target, which facilitates targeted drug release. NM-based DDS is being applied for treating cancer, arthritis, cardiovascular diseases, and dermal and ophthalmic diseases. Metal nanomaterials and carbon quantum dots are synthesized and stabilized using functional molecules extracted from natural sources. Polymers, mucilage and gums, exosomes, and molecules with biological activities are directly derived from natural sources. In DDS, these functional components have been used as drug carriers, imaging agents, targeting moieties, and super disintegrants. Plant extracts, biowaste, biomass, and microorganisms have been used as the natural source for obtaining these NMs. This review highlights the natural sources, synthesis, and application of metallic materials, polymeric materials, carbon dots, mucilage and gums, and exosomes in DDS. Aside from that, challenges and future perspectives on using natural resources for DDS are also discussed.

6.
Gels ; 9(7)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37504464

RESUMEN

Gel polymer electrolytes (GPEs) hold tremendous potential for advancing high-energy-density and safe rechargeable solid-state batteries, making them a transformative technology for advancing electric vehicles. GPEs offer high ionic conductivity and mechanical stability, enabling their use in quasi-solid-state batteries that combine solid-state interfaces with liquid-like behavior. Various GPEs based on different materials, including flame-retardant GPEs, dendrite-free polymer gel electrolytes, hybrid solid-state batteries, and 3D printable GPEs, have been developed. Significant efforts have also been directed toward improving the interface between GPEs and electrodes. The integration of gel-based electrolytes into solid-state electrochemical devices has the potential to revolutionize energy storage solutions by offering improved efficiency and reliability. These advancements find applications across diverse industries, particularly in electric vehicles and renewable energy. This review comprehensively discusses the potential of GPEs as solid-state electrolytes for diverse battery systems, such as lithium-ion batteries (LiBs), lithium metal batteries (LMBs), lithium-oxygen batteries, lithium-sulfur batteries, zinc-based batteries, sodium-ion batteries, and dual-ion batteries. This review highlights the materials being explored for GPE development, including polymers, inorganic compounds, and ionic liquids. Furthermore, it underscores the transformative impact of GPEs on solid-state batteries and their role in enhancing the performance and safety of energy storage devices.

7.
Cell Signal ; 110: 110827, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37506859

RESUMEN

Mesenchymal stem cells (MSCs) repair tissue injury by upregulating the paracrine secretion of cytokines and growth factors. Human MSC has been recognized as a promising therapeutic material for treatment of various human diseases. Even though the effect of epidermal growth factor (EGF) has been well investigated, the synergetic effect of EGF and MSC has not been studied. Therefore, we expect our basic study to contribute to developing new therapeutic reagents for skin diseases or innovative cosmetics. In this study, we examined the effect of human epidermal growth factor-transfected MSCs (hEGF MSCs) on human keratinocyte HaCaT cell proliferation and the mechanisms that regulate matrix metalloproteinase (MMP)-1 expression in HaCaT cells. To identify the hEGF plasmid and its transfection into MSCs, we performed gel electrophoresis and quantitative PCR. Proliferation and migration of HaCaT cells were examined using water Soluble Tetrazolium (WST-1) and wound-healing assays, respectively. Zymography was performed to investigate the correlation between hEGF MSC-conditioned medium (CM)-treated HaCaT cells and MMP-1 expression. We found that cell proliferation and wound-healing rates were increased in hEGF MSC-CM-treated HaCaT cells compared to those in MSC-CM-treated cells, and conversely collagenase activity was decreased. The mRNA and protein levels of MMP-1 were also decreased in hEGF MSC-CM-treated HaCaT cells. 2-DE analysis showed that the expression of carboxypeptidase, which promotes growth factors and wound healing, was increased in hEGF MSC-CM-treated HaCaT cells. Finally, western blot was used to determine whether MMP-1 expression was reduced via the mitogen-activated protein kinase (MAPK) pathway; the results showed that the levels of MAPK pathway-related proteins (pErk, pJNK, and p-p38) and the levels of transcription factors (pCREB, NFκB, and p-c-Fos) were decreased. In addition, pAkt expression was found to be elevated. The results of our study suggest that hEGF MSCs promote cell proliferation and reduce MMP-1 expression via the MAPK pathway in human keratinocyte HaCaT cells.


Asunto(s)
Factor de Crecimiento Epidérmico , Células Madre Mesenquimatosas , Humanos , Factor de Crecimiento Epidérmico/metabolismo , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Queratinocitos/metabolismo , Proliferación Celular , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Medios de Cultivo Condicionados/farmacología
9.
Chemosphere ; 310: 136881, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36257391

RESUMEN

Pollution of the environment by heavy metals (HMs) has recently become a global issue, affecting the health of all living organisms. Continuous human activities (industrialization and urbanization) are the major causes of HM release into the environment. Over the years, two methods (physical and chemical) have been widely used to reduce HMs in polluted environment. However, these two methods are inefficient and very expensive to reduce the HMs released into the atmosphere. Alternatively, researchers are trying to remove the HMs by employing hyper-accumulator plants. This method, referred to phytoremediation, is highly efficient, cost-effective, and eco-friendly. Phytoremediation can be divided into five types: phytostabilization, phytodegradation, rhizofiltration, phytoextraction, and phytovolatilization, all of which contribute to HMs removal from the polluted environment. Brassicaceae family members (particularly Arabidopsis thaliana) can accumulate more HMs from the contaminated environment than those of other plants. This comprehensive review focuses on how HMs pollute the environment and discusses the phytoremediation measures required to reduce the impact of HMs on the environment. We discuss the role of metal transporters in phytoremediation with a focus on Arabidopsis. Then draw insights into the role of genome editing tools in enhancing phytoremediation efficiency. This review is expected to initiate further research to improve phytoremediation by biotechnological approaches to conserve the environment from pollution.


Asunto(s)
Arabidopsis , Metales Pesados , Contaminantes del Suelo , Arabidopsis/metabolismo , Biodegradación Ambiental , Proteínas de Transporte de Membrana/metabolismo , Metales Pesados/análisis , Plantas/metabolismo , Suelo/química , Contaminantes del Suelo/análisis
10.
Environ Res ; 208: 112724, 2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35026186

RESUMEN

Pollution by microplastics (MPs) formed by the physicochemical breakdown of plastics are a worldwide issue with long-lasting and hazardous natural effects. The natural expulsion of MPs takes several years and can be dangerous. Several effective technological innovations have been developed over the years to remediate harmful MPs. Among them, a blend of nanotechnological techniques using bionanomaterials has been investigated to a large extent. The objective of this review is to compile the MPs found in the environment and bionanomaterial-based approaches for their removal. This information is important for researchers who are exploring the adverse consequences of MPs and their remediation and developing advanced eco-friendly strategies to control and eradicate MPs in the future. The control and eradication of MPs depend on all of us; hence, the proper awareness of MPs pollution must be provided to every individual, as all of us are a part of the environment.


Asunto(s)
Salud Poblacional , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Contaminación Ambiental/prevención & control , Humanos , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis
11.
J Hazard Mater ; 421: 126720, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34343883

RESUMEN

An emerging global necessity for alternative resources combined with maximum catalytic efficiency, low cost, and eco-friendly composite remains a hotspot in the scientific society. Hereby, a novel protocol is approached to design a heterostructure of Zinc MOF decorated on the surface of 2D activated carbon (AC) through a simplistic approach. To begin with, analytical, morphological and spectroscopical studies were performed to identify the functional moieties, cruciate-flower like morphology and oxidative state of atoms present in the composite Zn-MOF @AC. The photocatalytic material aids in degrading both cationic and anionic dye in a UV (254 nm) irradiated environment at a rate of 86.4% and 77.5% within 90 mins. Subsequently, the hybrid materials are coated on the carbon substrate to evaluate the catalytic activity using oxygen evolution and reduction reaction process. The mechanical insight for the catalytic activity relies on the electronic transitions of atoms on the edges of the sheets ascribing to d-d energy levels between the interfacial electron movement. Our composite exhibits an overpotential of 0.7 V and a Tafel slope of 70 mV/dec for the oxygen reduction reaction. This study proposes an alternate approach for developing MOF decorated carbon-based composites for photocatalytic degradability and energy necessity.


Asunto(s)
Carbón Orgánico , Oxígeno , Catálisis , Oxidación-Reducción , Zinc
12.
Environ Res ; 205: 112201, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34655605

RESUMEN

To materialize the excellent photocatalyst for crystal violet dye-degradation, the graphitic carbon-encapsulated vanadium pentoxide (GC-V2O5) nanocomposites were synthesized through the simple sonication method by using the green tea waste-derived GC nanoflakes and the sonochemically synthesized V2O5 nanorods. The nanocomposites were confirmed to comprise an aggregated morphology, in which the orthorhombic V2O5 nanorods were well anchored with the intertwingled GC nanoflakes. Owing to the encapsulation of defective V2O5 by conductive GC, the GC-V2O5 nanocomposites exhibited the enhanced photocatalytic dye-degradation efficiency up to 98.4% within 105 min. Namely, the encapsulated GC nanosheets might compensate the native defects (i.e., charge traps) on the V2O5 surface; hence, the charge transport could be enhanced during the dye-degradation process while the photocarrier recombination could be suppressed. The results suggest the conducting layer-encapsulated semiconducting oxide nanocomposites (e.g., GC-V2O5) to be of good use for future green environmental technology, particularly, as a superb photocatalyst for dye degradation.


Asunto(s)
Grafito , Nanocompuestos , Carbono , Catálisis , Violeta de Genciana , Grafito/química
13.
Chemosphere ; 286(Pt 3): 131893, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34403903

RESUMEN

Facile and modest synthesis of significantly effective and less-cost catalysts for environmental pollutant degradation and oxygen evolution holds substantial potential in environmental and energy fields. Hereby, Trimetallic organic frameworks (TriMOF) consisting of Fe, Co, and Zn synergized on the surface of activated carbon (AC) from pineapple leaves tend to show exponential catalytic activity due to the more excellent ionic conductivity, catalytic stability and multiple active sites provided by different metal precursors. Furthermore, the developed nanocomposite was coated on the stainless-steel electrode substrate at room temperature, delivering greater electrocatalytic surface area and numerous active sites. The oxidation reaction kinetics drives the catalytic reduction of 4-nitrophenol to 4-aminophenol with a minimal time of 12 min @ >97 % efficiency. Furthermore, on electrocatalytic oxidation of water splitting process due to the presence of multiple metallic, active sites, the overpotential is at 370 mV having Tafel slope of 40 mV/dec and electrochemically active surface area of is 9.9 mF/cm2. This superior catalytic reduction of 4-nitrophenol and electrocatalytic water oxidation process is attributed to the developed composite's active centre and conductivity.


Asunto(s)
Ananas , Contaminantes Ambientales , Carbón Orgánico , Oxígeno , Hojas de la Planta
14.
Chemosphere ; 286(Pt 1): 131598, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34325269

RESUMEN

This report details the preparation, characterization, and applications of an inexpensive adsorbent obtained from Azadirachta indica leaves (Neem biochar (NBC)) and used to remove Cr(VI) from the synthetic waste water. The obtained NBC was characterized by XRD, FTIR, FESEM, EDX and Zeta potential measurements. Adsorption experiments conducted at various pH levels confirmed that 58.54 mg g-1 of Cr(VI) was removed by NBC at pH 2. Experiments conducted at various temperatures revealed that the Cr(VI) adsorption on NBC fits the Langmuir-type adsorption isotherm. A fixed-bed column study was conducted to obtain breakthrough curve for the adsorption process, which confirmed that the NBC usage rate was 4.63 g/L. Cr(VI)NBC was reactivated by NaOH treatment, and the reactivated NBC was used as a sorbent to remove fresh Cr(VI) from the synthetic waste water repeatedly. A cost analysis was also performed for the Cr(VI) removal confirmed that the process was less expensive.


Asunto(s)
Azadirachta , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Cromo/análisis , Concentración de Iones de Hidrógeno , Cinética , Hojas de la Planta/química , Contaminantes Químicos del Agua/análisis
15.
J Hazard Mater ; 421: 126747, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34364210

RESUMEN

The synthesis of Bi2WO6 and CeO2 photocatalytic nanomaterials exhibit a great ability to photodegrade the antibiotics and shown excellent oxidation of various organic pollutants. Heterostructure 1:1 & 2:1 Bi2WO6/CeO2 nanocomposite was successfully synthesized via the facile sono-dispersion method and exquisite photocatalytic activity. The 0.5 wt% of nanocomposites were well-grafted on PVDF membrane surface via an in-situ polymerization method using polyacrylic acid. The fourier transform infrared (FTIR) spectra demonstrated that the network formation in PVDF induced by the -COOH functional group in acrylic acid. The grafted membrane morphology and strong binding ability over the membranes were validated by scanning electron microscope with energy dispersion (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), respectively. The permeate flux of 49.2 L.m-2 h-1 and 41.65 L.m-2 h were observed for tetracycline and the humic acid solution respectively for 1 wt% of PVP and 0.5 wt% of photocatalytic nanomaterials in PVDF membrane. The tetracycline and humic acid photodegradation rate of 82% and 78% and total resistance of 1.43 × 1010 m-1 and 1.64 × 1010 m-1, 83.5% and 77% flux recovery ratio were observed with N5 membrane. The 2:1 Bi2WO6/CeO2 nanocomposite grafted membrane showed a high permeate flux and better photodegradation ability of organic pollutants in the wastewater.


Asunto(s)
Sustancias Húmicas , Tetraciclina , Antibacterianos , Catálisis , Polivinilos
16.
Chemosphere ; 287(Pt 1): 131915, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34455121

RESUMEN

Carbon quantum dots (CQDs) synthesized from biological sources play a significant role in biomedical and environmental applications, including bioimaging, biosensing, metal ions detection and electrocatalytic oxidations. Herein, we synthesized blue-emitting carbon quantum dots using maple tree leaves via a one-step hydrothermal process to detect Cesium ions selectively. The synthesized CQDs' functional group composition, morphology, and pH stability was analytical and morphologically investigated. The maple leaves derived carbon quantum dots (M-CQDs) exhibited blue fluorescence, and their sizes ranged from 1 to 10 nm. They exhibited emission at 445 nm upon excitation at 360 nm. M-CQDs PL intensity was highly stable for about 100 d without any changes and confirmed that the as-prepared CQDs could be used as a probe for Cesium ion sensing. M-CQDs were effectively used as Cesium sensing probes based on the electron transfer process and simultaneously used as a catalyst for glycerol electrooxidation. The PL intensity of M-CQDs was quenched while adding the varies concentration of Cesium ions in the linear range from 100 µM to 100 nM with the detection limit of (LOD) 160 nM, simultaneously electrocatalytic oxidation of glycerol showed an onset potential of 1.32 V at a current density of 10 mA/cm2.


Asunto(s)
Acer , Puntos Cuánticos , Carbono , Cesio , Glicerol , Hojas de la Planta , Árboles
17.
Environ Res ; 204(Pt B): 112050, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34516981

RESUMEN

The two-dimensional carbonaceous nanocomposites tend to have extreme capacitance and catalysis activity because of their surface tunability of oxygenated moieties aiding in photocatalytic degradation. Herewith, we performed microwave-assisted alkaline treatment of graphene oxide sheets to attain defective sites on the graphitic surface by altering microwave parameters. The synergism of zinc oxide (ZnO) on the graphitic surface impacts electronic transitions paving paths for vacant oxygen sites to promote photocatalytic degradation and catalytic activity. The photocatalytic efficiency of the synthesized material for the degradation of rhodamine B (RhB) because of its susceptibility in industrial effluents, and the degradation rate was estimated to be around 87.5% within a short span of 30 min by utilizing UV irradiation. Concomitantly, the pGO/ZnO coated substrate exhibits a specific capacity of 561.7 mAh/g and incredible coulombic efficiency illustrating pseudocapacitive nature. Furthermore, on subjecting the composite modified electrode to oxygen evolution catalysis due to the vacant sites located at the lattice edges attributing to the d-d coulombic interaction within the local electron clouds possessing a low overpotential of 205 mV with a Tafel slope of 84 mV/dec. This modest approach boosts an eco-friendly composite to develop photocatalytic degradability and bifunctional catalytic activity for futuristic necessity.


Asunto(s)
Nanocompuestos , Óxido de Zinc , Catálisis , Electrónica , Rayos Ultravioleta
18.
Mater Today Bio ; 12: 100168, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34877521

RESUMEN

A simple, cost-effective system was developed for dopamine (DA) detection using green synthesized 1-6 â€‹nm honey-based carbon quantum dots (H-CQDs) exhibiting bluish green fluorescence. The H-CQDs exhibited emission at 445 â€‹nm, with a quantum yield of ∼44%. The H-CQDs were used as a probe for electron transfer based DA detection and changes in H-CQD color in the presence of DA. The H-CQDs were formed with polar functional groups and were highly soluble in aqueous media. In the fluorometric mode, the proposed system demonstrated high specificity toward DA and effective limit of detection (LOD) values of 6, 8.5, and 8 â€‹nM in deionized (DI) water, male geriatric plasma, and female geriatric plasma, respectively, in the linear range 100 â€‹nM-1000 µM. In the colorimetric mode, the color changed within 5 â€‹min, and the LOD was 163 â€‹µM. A colorimetric sensor array system was used to precisely detect DA with a smartphone-integrated platform using an in house built imaging application and an analyzer app. Additionally, no additives were required, and the H-CQDs were not functionalized. More importantly, the H-CQDs were morphologically and analytically characterized before and after DA detection. Because the sensor array-based system allows high specificity DA detection in both DI water and geriatric plasma, it will play an important role in biomedical applications.

19.
Nano Converg ; 8(1): 32, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34694514

RESUMEN

As the second wave of COVID-19 hits South Asia, an increasing deadly complication 'fungal infections (such as Mycosis, Candida and Aspergillus) outbreak' has been raised concern about the insufficient technologies and medicals for its diagnosis and therapy. Biosilica based nano-therapy can be used for therapeutic efficacy, yet their direct role as antibiotic agent with biocompatibility and stability remains unclear. Here, we report that a diatomaceous earth (DE) framework semiconductor composite conjugated DE and in-house synthesized zinc oxide (DE-ZnO), as an antibiotic agent for the enhancement of antibiotic efficacy and persistence. We found that the DE-ZnO composite had enhanced antibiotic activity against fungi (A. fumigatus) and Gram-negative bacteria (E. coli, S. enterica). The DE-ZnO composite provides enhancing large surface areas for enhancement of target pathogen binding affinity, as well as produces active ions including reactive oxygen species and metal ion for breaking the cellular network of fungi and Gram-negative bacteria. Additionally, the toxicity of DE-ZnO with 3 time less amount of dosage is 6 times lower than the commercial SiO2-ZnO. Finally, a synergistic effect of DE-ZnO and existing antifungal agents (Itraconazole and Amphotericin B) showed a better antifungal activity, which could be reduced the side effects due to the antifungal agents overdose, than a single antibiotic agent use. We envision that this DE-ZnO composite can be used to enhance antibiotic activity and its persistence, with less-toxicity, biocompatibility and high stability against fungi and Gram-negative bacteria which could be a valuable candidate in medical science and industrial engineering.

20.
Environ Pollut ; 289: 117861, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34343751

RESUMEN

The hydrothermal preparation of o-dianisidine and triazine interlinked porous organic polymer and its successive derivatisation via metal infusion (Ni, Cu) under hydrothermal and calcination conditions (700 °C) to yield pristine (ANIPOP-700) and Ni/Cu decorated porous carbon are described here (Ni-ANIPOP-700 and Cu-ANIPOP-700). To confirm their chemical and morphological properties, the as-prepared materials were methodically analyzed using solid state 13C and 15N NMR, X-ray diffraction, Raman spectroscopy, field emission scanning and high resolution transmission electron microscopic techniques, and x-ray photoelectron spectroscopy. Furthermore, the electrocatalytic activities of these electrocatalysts were thoroughly investigated under standard oxygen evolution (OER) and hydrogen evolution reaction (HER) conditions. The results show that all of the materials demonstrated significant activity in water splitting as well as displayed excellent stability (22 h) in both acidic (HER) and basic conditions (OER). Among the electrocatalysts reported in this study, Ni-ANIPOP-700 exhibited a lower overpotential η10 of 300 mV in basic medium (OER) and 150 mV in acidic medium (HER), as well as a lower Tafel slope of 69 mV/dec (OER) and 181 mV/dec (HER), indicating 30% lower energy requirement for overall water splitting. Gas chromatography was used to examine the electrolyzed products.


Asunto(s)
Carbono , Polímeros , Electrólisis , Porosidad , Agua de Mar
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