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1.
ACS Omega ; 9(21): 22979-22989, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38826557

ABSTRACT

Liver diseases pose a significant global health burden, with limited therapeutic options for chronic cases. Zinc oxide (ZnO) nanomaterials have emerged as promising candidates for hepatoprotection due to their antioxidant, anti-inflammatory, and regenerative properties. However, their potential remains hampered by insufficient drug loading and controlled release. The current study explores the intercalation of Naproxen (Nx), a potent anti-inflammatory and analgesic drug, within ZnO stacked nanosheets (SNSs) to address these limitations. Herein, an easy and solution-based synthesis of novel Nx intercalated ZnO SNSs was established. The obtained Nx intercalated ZnO SNSs were encapsulated with poly(vinyl acetate) (PVA) to make them biocompatible. The synthesized biocomposite was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR), which confirm the successful synthesis and intercalation of Nx within the ZnO SNSs. The obtained outcomes showed that the configuration of ZnO nanosheets was altered when Nx was introduced, resulting in a more organized stacking pattern. An in vivo investigation of mice liver cells unveiled that the Nx intercalated ZnO SNss had increased hepatoprotective properties. The study's results provide valuable insights into using Nx intercalated ZnO SNss for targeted drug delivery and improved treatment effectiveness, particularly for liver-related illnesses.

2.
Microsc Res Tech ; 87(7): 1654-1662, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38468512

ABSTRACT

Silver infused ultrathin TiO2 nanowires (NWs) were synthesized via a single step solvothermal approach. The crystallinity, structure, and morphology were determined to understand the physicochemical nature of the nanocomposites. The catalytic efficiency of the newly synthesized nanocatalysts was tested for the textile waste treatment taking methylene blue (MB) as model pollutant under solar light irradiations. Nearly 96% photodegradation efficiency for MB was achieved within 20 min. Furthermore, the recyclability of the photocatalyst was also studied, and the material remained stable and effective up to four consecutive runs. RESEARCH HIGHLIGHTS: Precise size-controlled synthesis of Ag-incorporated titania nanowires (ATNWs) Controlled aspect ratios, with tunable lengths and diameters (100-3 nm) via precursor and surfactant optimization Demonstrated ATNWs' efficiency in degrading toxic dye, methylene blue (MB) 96% photodegradation efficiency for MB achieved within 20 min using 3 nm thick annealed TiO2 NWs Recyclability efficiency of photocatalyst, which remained stable and effective for up to four consecutive runs.

3.
Small Methods ; : e2301432, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38213012

ABSTRACT

The self-assembly of inorganic nanocrystals offers an efficient way for the fabrication of functional materials. However, it is still challenging for the construction of multidimensional nanostructures with controllable shapes, compositions and functions. Here, a series of heterostructures in different dimensions by surface modification of polyoxometalate (POM) clusters is developed. Three kinds of POM clusters (phosphomolybdic acid (PMA), phosphotungstic acid (PTA) and silicotungstic acid (STA) and five kinds of metal oxides (TiO2 , VOx , La2 O3 , In2 O3 and Gd2 O3 ) can be used as building blocks, and a class of 1D, 2D and 3D heterostructures can be achieved by the control of surface ligand coverage. Compared with individual building blocks and other cluster-based superstructures, TiO2 -PMA superstructures exhibit enhanced catalytic activity toward thioether oxidations, which is attributed to the electron transfer between TiO2 and POM clusters.

4.
Heliyon ; 9(10): e20976, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37886752

ABSTRACT

A hydrothermal technique was employed to synthesize Ni/Mg/Al ternary L.D.H.s modified with montmorillonite (NMA-MMT-LDHs). Many characterization methods, including X-ray diffraction (XRD), scanning electron microscopy (S.E.M.), Fourier transform infrared (FTIR), and Brunauer, Emmett, and Teller (B.E.T.), were used to assess the physiochemical properties of the produced analytes. Congo red and methylene blue were utilized as model dyes to treat textile waste with the synthesized analytes. The batch adsorption model was utilized to conduct the adsorption experiments under varying contact time, adsorbent dosage, and solution pH conditions. A pseudo-second-order kinetics and the Langmuir adsorption model control the adsorption process. The maximum monolayer adsorption capacities of C.R. and M.B. were determined to be 344 and 200 mg/g, respectively. As the quantity of dosage increased from the 0.01-0.04 g, the percent removal efficiency (%) increased from 75 to 87 % for S2-LDH, 84-88 % for S2-MMT, 86-93 % for S3-MMT, and 95-97% for S4-MMT for C.R. dye and 82-85 % for S2-LDH, 83-89 % for S2-MMT, 83-91 % for S3-MMT, and 84-92 % for S4-MMT for M.B. dye. The removal percentage of C.R. dye for adsorbents S2-LDH, S2-MMT, S3-MMT, and S4-MMT were 75 %, 84 %, 86 %, and 95 %, respectively and 82 %, 83 %, 83 %, and 85 %, respectively for the M.B. dye removal. The presence of MMT significantly increases the affinity of Ni/Mg/Al-LDHs (NMA-LDHs), and the designed production technique can be used to produce a variety of compositionally distinct adsorbent materials.

5.
RSC Adv ; 13(33): 23038-23042, 2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37529361

ABSTRACT

At the ultrathin scale, nanomaterials exhibit interesting chemical and physical properties, like flexibility, and polymer-like rheology. However, to limit the dimensions of composite nanomaterials at the ultrathin level is still a challenging task. Herein, by adopting a new low temperature single step and single pot wet chemical approach, we have successfully fabricated two dimensional (2D) mixed oxide ZnO-Fe2O3 dendritic nanosheets (FZDNSs). Various control experimental outcomes demonstrate that precursor salts of both the metals are crucial for the formation of stable 2D FZDNSs. The obtained FZDNSs not only exhibit the best photoreduction performance but also much enhanced electrocatalytic performance. This work will provide a promising avenue for the synthesis of cost effective transition metal mixed oxide based 2D nanosheets having wide ranging applications.

6.
Nanoscale ; 14(42): 15635-15639, 2022 Nov 03.
Article in English | MEDLINE | ID: mdl-36193803

ABSTRACT

Free-standing 2D nanoassemblies are a new class of advanced functional materials that can integrate the unique properties of their individual components. Herein, we report a facile template-free solvothermal strategy to manipulate the assembly of structurally distinct building blocks into free-standing 2D quasi-nanosheets. The obtained 2D nanoassemblies are magnetic in nature with thickness in the range of tens of nanometers and lateral dimensions of several micrometers. They showed exceptionally high stability and can even remain intact in any solvent for months without any significant disassembly. The magnetic quasi-nanosheets were further used to remove polystyrene (PS), a model microplastic pollutant, from water. The robust phosphomolybdic acid (PMA) cluster-based hybrid exhibited outstanding PS removal performance because of the unique quasi-nanosheet architecture and multiple coordination sites of the redox-active PMA clusters. Overall, our developed co-assembly and subsequent water purification strategy effectively tackles various limitations associated with traditional assembly and water purification strategies.

7.
Nanomaterials (Basel) ; 11(12)2021 Dec 09.
Article in English | MEDLINE | ID: mdl-34947692

ABSTRACT

Owing to technological advancements and the ever-increasing population, the search for renewable energy resources has increased. One such attempt at finding effective renewable energy is recycling of lithium-ion batteries and using the recycled material as an electrocatalyst for the oxygen evolution reaction (OER) step in water splitting reactions. In electrocatalysis, the OER plays a crucial role and several electrocatalysts have been investigated to improve the efficiency of O2 gas evolution. Present research involves the use of citric acid coupled with lemon peel extracts for efficient recovery of lithium cobaltate from waste lithium-ion batteries and subsequent use of the recovered cathode material for OER in water splitting. Optimum recovery was achieved at 90 °C within 3 h of treatment with 1.5 M citric acid and 1.5% extract volume. The consequent electrode materials were calcined at 600, 700 and 800 °C and compared to the untreated waste material calcined at 600 °C for OER activity. The treated material recovered and calcined at 600 °C was the best among all of the samples for OER activity. Its average particle size was estimated to be within the 20-100 nm range and required a low overpotential of 0.55 V vs. RHE for the current density to reach 10 mA/cm2 with a Tafel value of 128 mV/dec.

8.
Nanomaterials (Basel) ; 11(6)2021 Jun 14.
Article in English | MEDLINE | ID: mdl-34198566

ABSTRACT

Graphitic carbon nitride modified by molybdenum trioxide (g-C3N4/MoO3) as a nanohybrid was synthesized by co-precipitation method. Here, g-C3N4/MoO3 nanohybrid was used for the first time as an adsorbent for the pharmaceutical drug, diclofenac, (an aqueous micropollutant) from water to mitigate its possible environmental toxic effects. Compared to pristine components, the nanohybrid exhibited better adsorptive removal of diclofenac. Adsorption was enhanced with increment in MoO3 content from 1 to 3 wt %; however further increment in MoO3 content resulted in lower adsorption capacity due to agglomeration of MoO3 particles over g-C3N4. 162 mg g-1 adsorption capacity was achieved for 300 mg L-1 diclofenac in solution with 1 g L-1 adsorbent at pH = 6. Adsorption of diclofenac over g-C3N4 /MoO3 followed pseudo 2nd order kinetics. Temkin, Langmuir, Dubinin Radushkevich and Freundlich isotherm models were applied on the experimental results concluding that diclofenac adsorption over g-C3N4/MoO3 followed the Langmuir isotherm. The adsorption mechanism could be explained by the π-π interaction between aromatic rings of diclofenac and g-C3N4/MoO3 (3%) nanohybrid, which is also evident by the FTIR results. This study presents the facile fabrication of a 2nd generation adsorbent for the treatment of diclofenac contaminated water that may as well help achieve the removal of other micropollutants form water.

9.
Microsc Res Tech ; 84(3): 480-488, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32979017

ABSTRACT

Design and synthesis of bactericidal and fungicidal agents is very important to protect human beings from different diseases. Silver nanoparticles (AgNPs) possess good bactericidal properties. Synthesis of these nanoparticles (NPs) via green route is cost-effective and environmentally harmonious as compared to the chemical and physical approaches. In this work, AgNPs were synthesized through green synthesis method using Populus ciliata leaf extract. The synthesized AgNPs were characterized by x-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive x-ray (EDX) techniques. The XRD pattern depicted the characteristic Bragg's peaks of (111), (200), (220), and (311) planes which are the features of face centered cubic (FCC) geometry of the synthesized AgNPs. TEM micrographs revealed the spherical shaped particles having average size of 4 nm. The AgNPs showed inhibitory effects against selected gram positive (Staphylococcus epidermidis and Streptococcus pyogenes) and gram negative bacteria (Klebsiella pneumoniae, Serratia marcescens, and Pseudomonas pseudoalcaligenes). The maximum zone of inhibition (26 mm) was observed for gram negative bacterium (Serratia marcescens) when 25 mg/ml solution of AgNPs was used and for similar concentration of these NPs, the maximum zone of inhibition (25 mm) was observed against gram positive bacteria (S. pyogenes). The results indicated good bactericidal potential of the synthesized AgNPs. RESEARCH HIGHLIGHTS: Populus ciliata leaf extract mediated synthesis of AgNPs. Transmission electron microscopy analysis revealed very small size of the synthesized AgNPs (4 nm). The synthesized AgNPs were found very effective against various bacterial pathogens.


Subject(s)
Ciliophora , Metal Nanoparticles , Populus , Anti-Bacterial Agents/pharmacology , Humans , Plant Extracts/pharmacology , Silver/pharmacology , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
10.
Sci Rep ; 10(1): 14191, 2020 08 25.
Article in English | MEDLINE | ID: mdl-32843698

ABSTRACT

In this study, bismuth oxychloride/graphene oxide (BiOCl-GO) composite was fabricated by facile one pot hydrothermal method. The pure BiOCl and BiOCl-GO composite was characterized by X-ray diffraction, Transmission electron microscopy X-ray photoelectron spectroscopy and UV-Vis diffuse reflectance spectroscopy. The synthesized composite was then assessed for photocatalytic degradation of diclofenac sodium (DCF) in visible as well as direct solar light and UV irradiation. Results indicated that the photocatalytic removal efficiency of DCF was significantly affected by dose of catalysts, pH value and source of light. The results reveled that degradation efficiency of BiOCl-GO for DCF reduced from 100 to 34.4% with the increases in DCF initial concentration from 5 mg L-1 to 25 mg L-1. The solar light degradation of DCF using BiOCl-GO was achieved with apparent rate constant 0.0037 min-1. The effect of scavengers study revealed that superoxide ions and holes were mainly responsible for DCF degradation. The regeneration study indicates that BiOCl-GO composite can be successfully recycled up to the five cycles. The study revealed the effectiveness of one pot hydrothermal method for the fabrication of BiOCl-GO composite.

11.
Sci Rep ; 10(1): 9707, 2020 Jun 16.
Article in English | MEDLINE | ID: mdl-32546696

ABSTRACT

Herein, we report the synthesis of Cr incorporated ZnO sheets arrays microstructures and construction of photoelectrode through a direct aerosol assisted chemical vapour deposition (AACVD) method. The as-prepared Cr incorporated ZnO microstructures were characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, powdered X-ray spectroscopy, X-ray photoelectron spectroscopy and UV-Vis diffused reflectance spectroscopy. The Cr incorporation in ZnO red shifted the optical band gap of as-prepared photoanodes. The 15% Cr incorporation in ZnO has shown enhanced PEC performance. The AACVD method provides an efficient in situ incorporation approach for the manipulation of morphological aspects, phase purity, and band structure of photoelectrodes for an enhanced PEC performance.

12.
J Pak Med Assoc ; 70(12(A)): 2154-2158, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33475589

ABSTRACT

OBJECTIVE: To determine the management of professionalism issues by foreign returned doctors who are practicing clinicians after returning from abroad. METHODS: The qualitative study was conducted in tertiary care hospitals of Khyber Pakhtunkhwa province from January to August 2016. Purposive sampling technique was used to include foreign returned doctors who shared how they managed professionalism matters in context of contrasting cultures at home and abroad. The participants were interviewed in-depth and the audio records were transcribed verbatim. The data analysis generated codes that were consolidated under categories and then themes. RESULTS: Interviews with ten foreign returned doctors led to 20 codes that resulted in eight categories out of which four main themes were developed namely; Foreign Cultural influence that observed how their stay abroad have influenced their practice methods. Experience, showed how personal experiences of the interviewees helped forge their practice rules in Pakistan. Social Contract theme included the ways in which foreign returned doctors understood and accepted the concept of social contract in Pakistan as compared to west and how they adapted accordingly. Wise Man Approach included the help sought and received by foreign returned doctors from their senior colleagues in managing and adjusting to societal norms regarding professional behaviours in Pakistan. CONCLUSION: There are multiple dissimilarities between the socio cultural aspects, practices and knowledge of foreign returned and local medical practitioners. There exists a gap in knowledge with regards to their clinical practice between foreign returned and local doctors. To authors knowledge foreign returned doctors face substantial challenges with adjustment in Pakistan.


Subject(s)
Physicians , Professionalism , Humans , Male , Pakistan , Qualitative Research
13.
Angew Chem Int Ed Engl ; 59(22): 8497-8501, 2020 May 25.
Article in English | MEDLINE | ID: mdl-31573137

ABSTRACT

A single-step solution-based strategy is used to obtain 2D Janus-like free-standing ultrathin nanosheets build from two structurally unrelated species, that is, polyoxomolybdate (POM) and CoO. A controlled 2D-to-1D morphological transition was achieved by judiciously adjusting the solvent choice. These POM-CoO heterostructures can behave as an ideal catalyst for the epoxidation of styrene. Benefiting from their amphiphilic nature, these 2D POM-CoO nanosheets have also been used as surfactant to emulsify immiscible solvents. It is anticipated that structurally diverse polyoxometalates will offer promise as design elements for variety of structurally and compositionally tunable van der Waals integrated heteromaterials having a broad range applications.

14.
Adv Mater ; 32(2): e1906794, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31773834

ABSTRACT

A facile one-step solvothermal approach to engineer a van der Waals integrated heteromaterial self-assembled superstructure composed of two structurally distinct species that is polyoxomolybdate and zirconia (POM-ZrO2 ) is reported. Nonclassical aggregation-based self-assembly process grows the superstructure. The introduced POM not only behaves as a catalytically active component of the hybrid structure but also imparts flexibility to the developed POM-ZrO2 superstructures. The material shows high performance toward oxygenation of thioethers as a result of its morphology, composition, and structure. This growing strategy may introduce a viable pathway to the rational design of Van der Waals integrated complex hybrid, catalytically active assemblies with potential applications in different fields.

15.
Langmuir ; 35(32): 10246-10266, 2019 Aug 13.
Article in English | MEDLINE | ID: mdl-31330109

ABSTRACT

The self-assembly of ultrathin nanocrystals (UTNCs) into well-organized multidimensional superstructures is one of the key topics in material chemistry and physics. Highly ordered nanocrystal assemblies also known as superstructures or synthetic structures have remained a focus for researchers over the past few years due to synergy in their properties as compared to their components. Here, we aim to present the recent progress being made in this field with highlights of our research group endeavors in the engineering of self-assembled complex multidimensional superstructures of various inorganic materials, including polyoxometalates. The driving forces for the assembly process and its kinetics along with the potential applications associated with these unique ordered and spatially complex superstructures are also discussed.

16.
Sci Rep ; 9(1): 10202, 2019 07 15.
Article in English | MEDLINE | ID: mdl-31308407

ABSTRACT

Visible light active g-C3N4(0.94)/CeO2(0.05)/Fe3O4(0.01) ternary composite nanosheets were fabricated by facile co-precipitation routes. The density functional theory (DFT) computations investigated changes in geometry and electronic character of g-C3N4 with CeO2 and Fe3O4 addition. Chemical and surface characterizations were explored with XRD, XPS, SEM, TEM, PL, DRS and Raman measurements. DRS and PL spectroscopy evidenced the energy band gap tailoring from 2.68 eV for bulk g-C3N4 and 2.92 eV for CeO2 to 2.45 eV for the ternary nanocomposite. Efficient electron/hole pair separation, increase in red-ox species and high exploitation of solar spectrum due to band gap tailoring lead to higher degradation efficiency of g-C3N4(0.94)/CeO2(0.05)/Fe3O4(0.01). Superior sun light photocatalytic breakdown of 2-Chlorophenol was observed with g-C3N4 having CeO2 loading up to 5 wt%. In case of ternary nanocomposites deposition of 1 wt% Fe3O4 over g-C3N4/CeO2 binary composite not only showed increment in visible light catalysis as predicted by the DFT studies, but also facilitated magnetic recovery. The g-C3N4(0.94)/CeO2(0.05)/Fe3O4(0.01) nanosheets showed complete mineralization of 25 mg.L-1 2-CP(aq) within 180 min exposure to visible portion of sun light and retained its high activity for 3 consecutive reuse cycles. The free radical scavenging showed superoxide ions and holes played a significant role compared to hydroxyl free radicals while chromatographic studies helped establish the 2-CP degradation mechanism. The kinetics investigations revealed 2.55 and 4.04 times increased rate of reactions compared to pristine Fe3O4 and CeO2, showing highest rate constant value of 18.2 × 10-3 min-1 for the ternary nanocomposite. We present very persuasive results that can be beneficial for exploration of further potential of g-C3N4(0.94)/CeO2(0.05)/Fe3O4(0.01) in advance wastewater treatment systems.

17.
Cell Signal ; 61: 108-119, 2019 09.
Article in English | MEDLINE | ID: mdl-31132399

ABSTRACT

BACKGROUND: Endothelial dysfunction is a hallmark of cerebrovascular disease, including ischemic stroke. Modulating endothelial signalling by cyclic nucleotides, cAMP and cGMP, is a potential therapeutic target in stroke. Inhibitors of the cyclic nucleotide degrading phosphodiesterase (PDE) enzymes may restore cerebral endothelial function. Current knowledge on PDE distribution and function in cerebral endothelial cells is sparse. This review explores data on PDE distribution and effects of PDEi in cerebral endothelial cells and identifies which PDEs are potential treatment targets in stroke. METHOD: We performed a systematic search of electronic databases (Medline and Embase). Our search terms were cerebral ischaemia, cerebral endothelial cells, cyclic nucleotide, phosphodiesterase and phosphodiesterase inhibitors. RESULTS: We found 23 publications which described effects of selective inhibitors of only three PDE families on endothelial function in ischemic stroke. PDE3 inhibitors (PDE3i) (11 publications) and PDE4 inhibitors (PDE4i) (3 publications) showed anti-inflammatory, anti-apoptotic or pro-angiogenic effects. PDE3i also reduced leucocyte infiltration and MMP-9 expression. Both PDE3i and PDE4i increased expression of tight junction proteins and protected the blood-brain barrier. PDE5 inhibitors (PDE5i) (6 publications) reduced inflammation and apoptosis. In preclinical models, PDE5i enhanced cGMP/NO signalling associated with microvascular angiogenesis, increased cerebral blood flow and improved functional recovery. Non-specific PDEi (3 publications) had mainly anti-inflammatory effects. CONCLUSION: This review demonstrates that non-selective and selective PDEi of PDE3, PDE4 and PDE5 modulated endothelial function in cerebral ischemic stroke by regulating processes involved in vascular repair and neuroprotection and thus reduced cell death and inflammation. Of note, they promoted angiogenesis, microcirculation and improved functional recovery; all are important in stroke prevention and recovery, and effects should be further evaluated in humans.


Subject(s)
3',5'-Cyclic-AMP Phosphodiesterases/metabolism , Brain Ischemia/metabolism , Endothelial Cells/metabolism , Stroke/metabolism , 3',5'-Cyclic-AMP Phosphodiesterases/antagonists & inhibitors , Animals , Brain Ischemia/drug therapy , Cyclic AMP/metabolism , Cyclic GMP/metabolism , Endothelial Cells/drug effects , Humans , Neovascularization, Physiologic/drug effects , Neuroprotection/drug effects , Phosphodiesterase Inhibitors/pharmacology , Phosphodiesterase Inhibitors/therapeutic use , Recovery of Function/drug effects , Stroke/drug therapy
18.
Sci Bull (Beijing) ; 64(15): 1103-1109, 2019 Aug 15.
Article in English | MEDLINE | ID: mdl-36659771

ABSTRACT

Carboxylate-based metal-organic frameworks (CMOFs) have received considerable attentions for their high stability, catalytic activity, and porosity. However, synthesis of CMOFs requires high temperature, pressure, and long reaction time. Here, we explored the activity of 2-methylimidazole (2-MIM) for ultrafast synthesis of CMOF nanostructures (CMOFNs), in aqueous medium at room temperature and reaction time of 10 min. Seven CMOFNs have been synthesized by using Al3+, Cr3+, Cu2+, Fe3+, In3+, or Cd2+ salt and 1,4-bezenedicarboxylic acid, or 1,3,5-benzenetricarboxylic acid. Through this technique, the CMOFs with space time yield 181-501 kg m-3 day-1 and crystal sizes of ca. 200-700 nm was obtained.

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