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1.
Langmuir ; 39(6): 2333-2346, 2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36719844

ABSTRACT

Antifouling (AF) nanocoatings made of polydimethylsiloxane (PDMS) are more cost-efficient and eco-friendly substitutes for the already outlawed tributyltin-based coatings. Here, a catalytic hydrosilation approach was used to construct a design inspired by composite mosquito eyes from non-toxic PDMS nanocomposites filled with graphene oxide (GO) nanosheets decorated with magnetite nanospheres (GO-Fe3O4 nanospheres). Various GO-Fe3O4 hybrid nanofillers were dispersed into the PDMS resin through a solution casting method to evaluate the structure-property relationship. A simple coprecipitation procedure was used to fabricate magnetite nanospheres with an average diameter of 30-50 nm, a single crystal structure, and a predominant (311) lattice plane. The uniform bioinspired superhydrophobic PDMS/GO-Fe3O4 nanocomposite surface produced had a micro-/nano-roughness, low surface-free energy (SFE), and high fouling release (FR) efficiency. It exhibited several advantages including simplicity, ease of large-area fabrication, and a simultaneous offering of dual micro-/nano-scale structures simply via a one-step solution casting process for a wide variety of materials. The superhydrophobicity, SFE, and rough topology have been studied as surface properties of the unfilled silicone and the bioinspired PDMS/GO-Fe3O4 nanocomposites. The coatings' physical, mechanical, and anticorrosive features were also taken into account. Several microorganisms were employed to examine the fouling resistance of the coated specimens for 1 month. Good dispersion of GO-Fe3O4 hybrid fillers in the PDMS coating until 1 wt % achieved the highest water contact angle (158° ± 2°), the lowest SFE (12.06 mN/m), micro-/nano-roughness, and improved bulk mechanical and anticorrosion properties. The well-distributed PDMS/GO-Fe3O4 (1 wt % nanofillers) bioinspired nanocoating showed the least biodegradability against all the tested microorganisms [Kocuria rhizophila (2.047%), Pseudomonas aeruginosa (1.961%), and Candida albicans (1.924%)]. We successfully developed non-toxic, low-cost, and economical nanostructured superhydrophobic FR composite coatings for long-term ship hull coatings. This study may expand the applications of bio-inspired functional materials because for multiple AF, durability and hydrophobicity are both important features in several industrial applications.

2.
Mikrochim Acta ; 188(4): 138, 2021 03 26.
Article in English | MEDLINE | ID: mdl-33772377

ABSTRACT

An electrochemical sensor-based phosphorus-doped microporous carbon spheroidal structures (P-MCSs) has been designed for selective adrenaline (ADR) signaling in human blood serum. The P-MCS electrode sensor is built with heterogeneous surface alignments including multiple porous sizes with open holes and meso-/macro-grooves, rough surface curvatures, and integral morphology with interconnected and conjugated microspheres. In addition, the P atom-doped graphitic carbon forms highly active centers, increases charge mobility on the electrode surface, creates abundant active centers with facile functionalization, and induces binding to ADR molecules. The designed P-MCS electrode exhibits ultrasensitive monitoring of ADR with a low detection limit of 0.002 µM and high sensitivity of 4330 µA µM-1 cm-2. In addition, two electrochemical techniques, namely, square wave voltammetry (SWV) and chronoamperometry (CA), were used; these techniques achieve high stability, fast response, and a wide linear range from 0.01 to 6 µM. The sensing assays based on P-MCSs provide evidence of the formation of active interfacial surface-to-ADR binding sites, high electron diffusion, and heavy target loads along with/without a plane of spheroids. Thus, P-MCSs can be used for the routine monitoring of ADR in human blood serum, providing a fast response, and requiring highly economical materials at extremely low concentrations. Electrode surface modulation based on P-doped carbon spheres (P-MCS) exhibits high electrochemical activity with fast charge transport, multi-diffusible active centers, high loading of ADR, and facile molecular/electron diffusion at its surface. The P-MCS sensitively and selectively detects the ADR in human fluids and can be used for clinical investigation of some neuronal diseases such as Alzheimer diseases.


Subject(s)
Carbon/chemistry , Electrochemical Techniques/methods , Epinephrine/blood , Adsorption , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Electrochemical Techniques/instrumentation , Electrodes , Epinephrine/chemistry , Humans , Limit of Detection , Oxidation-Reduction , Phosphorus/chemistry , Porosity , Reproducibility of Results
3.
Analyst ; 139(24): 6393-405, 2014 Dec 21.
Article in English | MEDLINE | ID: mdl-25356759

ABSTRACT

High exposure to metals, such as cobalt (Co), copper (Cu) and cadmium (Cd), potentially has adverse effects, and can cause severe health problems, leading to a number of specific diseases. This study primarily aims to monitor, detect, separate, and remove the trace concentrations of Co(II), Cu(II), and Cd(II) ions in water, without a preconcentration process, using aluminosilica optical sensor (ASOS) monoliths. These monolithic scaffolds with advantageous physical features (i.e., large surface area-to-volume ratios of the scaffolds, active acid sites and uniform mesocage cubic pores) can strongly induce H-bonding and dispersive interactions with organic chelating agent, resulting in the formation of stable ASOS. In this engineering process, ASOS offers a simple and one-step sensing/capture procedure for the quantification and visual detection of the target elements from water, without requiring sophisticated instrumentation. The key result in this study is the ion selectivity exhibited by the designed ASOS toward the targets, Co(II), Cu(II), and Cd(II) ions, in environmental and waste disposal samples, as well as its reproducibility over a number of analysis/regeneration cycles. These findings can be useful in the fabrication of ASOS can be tailored to suit various applications.

4.
J Hazard Mater ; 465: 133271, 2024 03 05.
Article in English | MEDLINE | ID: mdl-38141313

ABSTRACT

The extraordinary accumulation of cyanide ions within biological cells is a severe health risk. Detecting and tracking toxic cyanide ions within these cells by simple and ultrasensitive methodologies are of immense curiosity. Here, continuous tracking of ultimate levels of CN--ions in HeLa cells was reported employing biocompatible branching molecular architectures (BMAs). These BMAs were engineered by decorating colorant-laden dendritic branch within and around the molecular building hollows of the geode-shelled nanorods of organic-inorganic Al-frameworks. Batch-contact methods were utilized to assess the potential of hollow-nest architecture for inhibition/evaluation of toxicant CN--ions within HeLa cells. The nanorod BMAs revealed significant potential capabilities in monitoring and tracking of CN- ions (88 parts per trillion) in biological trials within seconds. These results demonstrated sufficient evidence for the compatibility of BMAs during HeLa cell exposure. Under specific conditions, the BMAs were utilized for in-vitro fluorescence tracking/sensing of CN- in HeLa cells. The cliff swallow nest with massive mouths may have the potential to reduce the health hazards associated with toxicant exposure in biological cells.


Subject(s)
Metal-Organic Frameworks , Humans , HeLa Cells , Ions , Cyanides , Hazardous Substances
5.
Small ; 9(13): 2288-96, 2013 Jul 08.
Article in English | MEDLINE | ID: mdl-23359538

ABSTRACT

Methods for the continuous monitoring and removal of ultra-trace levels of toxic inorganic species (e.g., mercury, copper, and cadmium ions) from aqueous media such as drinking water and biological fluids are essential. In this paper, the design and engineering of a simple, pH-dependent, micro-object optical sensor is described based on mesoporous aluminosilica pellets with an adsorbed dressing receptor (a porphyrinic chelating ligand). This tailor-made optical sensor permits ultra-fast (≤ 60 s), specific, pH-dependent visualization and removal of Cu(2+) , Cd(2+) , and Hg(2+) at sub-picomolar concentrations (∼10(-11) mol dm(-3) ) from aqueous media, including drinking water and a suspension of red blood cells. The acidic active acid sites of the pellets consist of heteroatoms arranged around uniformly shaped pores in 3D nanoscale gyroidal mesostructures densely coated with the chelating ligand. The sensor can be used in batch mode, as well as in a flow-through system in which sampling, target ion recognition and removal, and analysis are integrated in a highly automated and efficient manner. Because the pellets exhibit long-term stability, reproducibility, and versatility over a number of analysis/regeneration cycles, they can be expected to be useful for the fabrication of inexpensive sensor devices for naked-eye detection of toxic pollutants.


Subject(s)
Metals/isolation & purification , Optics and Photonics/instrumentation , Water Pollutants, Chemical/isolation & purification , Animals , Anions/isolation & purification , Cations/isolation & purification , Hydrogen-Ion Concentration , Microscopy, Electron, Transmission , Porosity , Scattering, Small Angle , Spectrum Analysis , Temperature , X-Ray Diffraction
6.
Analyst ; 137(22): 5278-90, 2012 Nov 21.
Article in English | MEDLINE | ID: mdl-23012687

ABSTRACT

Optical captor design is necessary for the controlled development of a technique for detecting and removing heavy and toxic metals from drinking water with high flexibility and low capital cost. We designed chemical mesocaptors for optical separation/extraction and monitoring/detection of Cu(II) and Zn(II) ions from water even at trace concentration levels without a preconcentration process. The mesoporous aluminosilica carriers with three-dimensional (3D) structures, high aluminum content, natural surfaces, and active acid sites strongly induced H-bonding and dispersive interactions with organic moieties, thereby leading to the formation of stable captors without chromophore leaching during the removal assays of Cu(II) and Zn(II) ions. Using such a tailored mesocaptor design, the direct immobilization of these hydrophobic ligands (4,5-diamino-6-hydroxy-2-mercaptopyrimidine and diphenylthiocarbazone) into ordered pore-based aluminasilica monoliths enabled the easy generation and transduction of optical colour signals as a response to metal-to-ligand binding events, even at ultra-trace concentrations (~10(-9) mol dm(-3)) of Cu(II) and Zn(II) ions in drinking water, without the need for sophisticated instruments. Theoretical models have been developed to provide insights into the effect of active site surfaces on the enhancement of the optical removal process in terms of long-term stability, reversibility, and selectivity, hence allowing us to understand the role of mesoscopic geometry and nanoscale pore orientation of mesocaptors better. Generally, this ion-capture model enables the development of a simple and effective technique for effective wastewater treatment and management.

7.
Colloids Surf B Biointerfaces ; 210: 112228, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34839049

ABSTRACT

Follow up of neuronal disorders, such as Alzheimer's and Parkinson's diseases using simple, sensitive, and selective assays is urgently needed in clinical and research investigation. Here, we designed a sensitive and selective enzymeless electrochemical acetylcholine sensor that can be used in human fluid samples. The designed electrode consisted of a micro spherical construction of Cu-metal decorated by a thin layer of carbon (CuMS@C). A simple and one-pot synthesis approach was used for Cu-metal controller formation with a spherical like structures. The spherical like structure was formed with rough outer surface texture, circular build up, homogeneous formation, micrometric spheres size (0.5 -1 µm), and internal hollow structure. The formation of a thin layer of carbon materials on the surface of CuMS sustained the catalytic activity of Cu atoms and enriched negatively charge of the surface. CuMS@C acted as a highly active mediator surface that consisted of Cu metal as a highly active catalyst and carbons as protecting, charge transport, and attractive surface. Therefore, the CuMS@C surface morphology and composition played a key role in various aspects such as facilitated ACh diffusion/loading, increased the interface surface area, and enhanced the catalytic activity. The CuMS@C acted as an electroactive catalyst for ACh electrooxidation and current production, due to the losing of two electrons. The fabricated CuMS@C could be a highly sensitive and selective enzymeless sensor for detecting ACh with a detection limit of 0.1 µM and a wide linear range of 0.01 - 0.8 mM. The designed ACh sensor assay based on CuMS@C exhibited fast sensing property as well as sensitivity, selectivity, stability, and reusability for detecting ACh in human serum samples. This work presents the design of a highly active electrode surface for direct detection of ACh and further clinical investigation of ACh levels.


Subject(s)
Biosensing Techniques , Copper , Acetylcholine , Carbon , Electrochemical Techniques , Electrodes , Humans , Limit of Detection , Microspheres
8.
Anal Chim Acta ; 1192: 339380, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-35057967

ABSTRACT

To date, the production and development of portable analytical devices for environmental and healthcare applications are rapidly growing. Herein, a portable electrochemical sensor for monitoring of noradrenaline (NA) secreted from living cells using mesoporous carbon-based materials was fabricated. The modification of the interdigitated electrode array (IDA) by nitrogen-doped mesoporous carbon spheres (N-doped MCS) and nitrogen-doped carbon hollow trunk-like structure (N-doped CHT) was used to fabricate the NA sensor. The N-doped CHT surface shows multiple holes distributed with micrometer-sized open holes (1-2 µm) and nanometer-sized thin walls (∼98 nm). The N-doped CHT surface heterogeneity of wrinkled and twisted hollow trunk structures improve the diffusion pathway and the NA molecules loading. The N-doped CHT/IDA showed a highly selective assay for monitoring of NA with high sensitivity (1770 µA/µM × cm2), a low detection limit (0.005 µM), and a wide linear range (0.01-0.3 µM). The N-doped CHT/IDA monitored the NA secreted from PC12 cells under various concentrations of simulation agents (KCl). The designed N-doped CHT/IDA provides a portable NA-sensor assay with facile signaling, good stability, high biocompatibility, in-vitro assay compatibility, and good reproducibility. Therefore, the designed sensor can be used as a portable sensor for NA detection in live cells and can be matched with portable smartphones after further developments.


Subject(s)
Carbon , Nitrogen , Animals , Electrodes , Norepinephrine , Rats , Reproducibility of Results
9.
Nanomaterials (Basel) ; 12(3)2022 Feb 01.
Article in English | MEDLINE | ID: mdl-35159855

ABSTRACT

Bacterial pathogens pose high threat to public health worldwide. Different types of nanomaterials have been synthesized for the rapid detection and elimination of pathogens from environmental samples. However, the selectivity of these materials remains challenging, because target bacterial pathogens commonly exist in complex samples at ultralow concentrations. In this study, we fabricated novel furry amino magnetic poly-L-ornithine (PLO)/amine-poly(ethylene glycol) (PEG)-COOH/vancomycin (VCM) (AM-PPV) nanospheres with high-loading VCM for vehicle tracking and the highly efficient capture of pathogens. The magnetic core was coated with organosilica and functionalized with cilia. The core consisted of PEG/PLO loaded with VCM conjugated to Gram-positive bacterial cell membranes, forming hydrogen bonds with terminal peptides. The characterization of AM-PPV nanospheres revealed an average particle size of 56 nm. The field-emission scanning electron microscopy (FE-SEM) micrographs showed well-controlled spherical AM-PPV nanospheres with an average size of 56 nm. The nanospheres were relatively rough and contained an additional 12.4 nm hydrodynamic layer of PLO/PEG/VCM, which provided additional stability in the suspension. The furry AM-PPV nanospheres exhibited a significant capture efficiency (>90%) and a high selectivity for detecting Bacillus cereus (employed as a model for Gram-positive bacteria) within 15 min, even in the presence of other biocompatible pathogens. Moreover, AM-PPV nanospheres rapidly and accurately detected B. cereus at levels less than 10 CFU/mL. The furry nano-design can potentially satisfy the increasing demand for the rapid and sensitive detection of pathogens in clinical and environmental samples.

10.
Nanotechnology ; 22(48): 485503, 2011 Dec 02.
Article in English | MEDLINE | ID: mdl-22071572

ABSTRACT

Achieving proper designs of nanosensors for highly sensitive and selective detection of toxic environmental gases is one of the crucial issues in the field of gas sensor technology, because such designs can lead to the enhancement of gas sensor performance and expansion of their applications. Different geometrical designs of porous tungsten oxide nanostructures, including the mesocages, hollow spheres and nanowires, are synthesized for toxic gas sensor applications. Nanosensor designs with small crystalline size, large specific surface area, and superior physical characteristics enable the highly sensitive and selective detection of low concentration (ppm levels), highly toxic NO(2) among CO, as well as volatile organic compound gases, such as acetone, benzene, and ethanol. The experimental results showed that the sensor response was not only dependent on the specific surface area, but also on the geometries and crystal size of materials. Among the designed nanosensors, the nanowires showed the highest sensitivity, followed by the mesocages and hollow spheres-despite the fact that mesocages had the largest specific surface area of 80.9 m(2) g( - 1), followed by nanowires (69.4 m(2) g( - 1)), and hollow spheres (6.5 m(2) g( - 1)). The nanowire sensors had a moderate specific surface area (69.4 m(2) g( - 1)) but they exhibited the highest sensitivity because of their small diameter (∼5 nm), which approximates the Debye length of WO(3). This led to the depletion of the entire volume of the nanowires upon exposure to NO(2), resulting in an enormous increase in sensor resistance.


Subject(s)
Gases/analysis , Nanowires/ultrastructure , Oxides/chemistry , Tungsten/chemistry , Environmental Monitoring/methods , Microscopy, Electron , Nanostructures/chemistry , Nanostructures/ultrastructure , Nanowires/chemistry , Nitrogen Dioxide/analysis , Particle Size , Porosity , Temperature
11.
J Environ Sci (China) ; 23(12): 1947-54, 2011.
Article in English | MEDLINE | ID: mdl-22432323

ABSTRACT

A highly selective ligand exchange type adsorbent was developed for the removal of trace arsenic(V) (As(V)) and phosphate from water. This adsorbent was prepared by loading zirconium(IV) on monophosphonic acid resin. This adsorbent was able to remove toxic anions efficiently at wide pH ranges. However, low pH was preferable for maximum breakthrough capacity in an adsorption operation. The effect of a large amount of competing anions such as chloride, bicarbonate, and sulfate on the adsorption systems of As(V) and phosphate anions was investigated. The experimental findings revealed that the As(V) and phosphate uptakes were not affected by these competing anions despite the enhancement of the breakthrough points and total adsorption. Phosphate anion was slightly preferable than As(V) in their competitive adsorption by the adsorbent. The adsorbed As(V) and phosphate on the Zr(IV)-loaded resin were quantitatively eluted with 0.1 mol/L sodium hydroxide solution, and the adsorbent was regenerated by 0.5 mol/L sulfuric acid. During several cycles of adsorption-elution-regeneration operations, no Zr(IV) was detected in the column effluents. Therefore, the Zr(IV)-loaded monophosphonic acid resin is an effective ligand exchange adsorbent for removing trace concentrations of As(V) and phosphate from water.


Subject(s)
Arsenic/chemistry , Phosphates/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Zirconium/chemistry , Adsorption , Hydrogen-Ion Concentration , Ligands
12.
Biosens Bioelectron ; 185: 113237, 2021 Aug 01.
Article in English | MEDLINE | ID: mdl-33932881

ABSTRACT

On-demand screening, real-time monitoring and rapid diagnosis of ubiquitous diseases, such as diabetes, at early stages are indispensable in personalised treatment. Emerging impacts of nano/microscale materials on optical and portable biosensor strips and devices have become increasingly important in the remarkable development of sensitive visualisation (i.e. visible inspection by the human eye) assays, low-cost analyses and personalised home testing of patients with diabetes. With the increasing public attention regarding the self-monitoring of diabetes, the development of visual readout, easy-to-use and wearable biosensors has gained considerable interest. Our comprehensive review bridges the practical assessment gap between optical bio-visualisation assays, disposable test strips, sensor array designs and full integration into flexible skin-based or contact lens devices with the on-site wireless signal transmission of glucose detection in physiological fluids. To date, the fully modulated integration of nano/microscale optical biosensors into wearable electronic devices, such as smartphones, is critical to prolong periods of indoor and outdoor clinical diagnostics. Focus should be given to the improvements of invasive, wireless and portable sensing technologies to improve the applicability and reliability of screen display, continuous monitoring, dynamic data visualisation, online acquisition and self and in-home healthcare management of patients with diabetes.


Subject(s)
Biosensing Techniques , Wearable Electronic Devices , Glucose , Humans , Reproducibility of Results , Smartphone
13.
Anal Chim Acta ; 1142: 143-156, 2021 Jan 15.
Article in English | MEDLINE | ID: mdl-33280692

ABSTRACT

Sensory protocols for evaluation of DNA distortion due to exposure to various harmful chemicals and environments in living cells are needed for research and clinical investigations. Here, a design of non-metal sensory (NMS) electrode was built by using boron-doped carbon spherules for detection of DNA nucleobases, namely, guanine (Gu), adenine (Ad), and thymine (Th) in living cells. The key-electrode based nanoscale NMS structures lead to voids with a facile diffusion, and strong binding events of the DNA nucleobases. Furthermore, the NMS geometric structures would significantly create electrode surfaces with numerous centrally active sites, curvature topographies, and anisotropic spherules. The NMS shows potential as sensitive protocol for DNA-nucleobases in living cells exposed to oxidative stresses. In one-step signaling assay, NMS shows high signaling transduction of Gu-, Ad-, and Th-DNA nucleobases targets with ultra-sensitive and low detection limits of 3.0, 0.36, and 0.34 nM, respectively, and a wide linear range of up to 1 µM. The NMS design and protocol show evidence of the role of surface construction features and B-atoms incorporated into the graphitic carbon network for creating abundant active sites with facile electron diffusion and heavily target loads along with within-/out-plane circular spheres. Indeed NMS, with spherule-rich interstitial surfaces can be used for sensitive and selective evaluation of damaged-DNA to various dysfunctional metabolism in the human body.


Subject(s)
DNA , Thymine , Electrodes , Guanine , Humans , Oxidative Stress
14.
J Colloid Interface Sci ; 604: 61-79, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34265693

ABSTRACT

This study aimed to develop a highly selective extraction protocol for gold (AuIII) ions from electronic urban waste (EUW) using simple, low-cost Inorganic-organic mesoporous hybrid segregators. The unique features of mesoporous hybrid segregator architectures are of particular to ensure effective adsorption system in terms of selective and sensitive recovery of AuIII ions from EUW. The segregator platform featured 3D micrometric, mesocage double-serrated plant-leaf-like γ-Al2O3 sheets with hierarchy surfaces containing tri-modal mesopores interiorly and uniformly arranged toothed edges of ~20-40 and ~15 nm groove width and depth at the exterior surfaces, respectively. Rational incorporation of actively organic chelates into hierarchical γ-Al2O3 sheet platforms leads to the production of a couple of selective segregators 1 and 2 (namely, SC1 and SC2) for AuIII ions at specific conditions by applying batch and fixed-bed columnar techniques. The mesocage SC segregators offer a selective extraction approach of AuIII ions from mixed element contents released from a computer motherboard (CMB). Our finding indicated that the textural and hierarchal features of the mesocage SC segregators played key roles in the selective adsorption/recovery of AuIII ions at pH 2-2.5 with high capacity (136-141 mg/g range) and effective reusability ≫10 consecutive cycles. In general, the developed SCs could be utilized as a real extractor of AuIII recovery from spent CMBs.


Subject(s)
Chelating Agents , Gold , Adsorption , Cell Membrane
15.
Mater Sci Eng C Mater Biol Appl ; 122: 111844, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33641886

ABSTRACT

Here, we study the effect of hierarchical and one-dimensional (1D) metal oxide nanorods (H-NRs) such as γ-Al2O3, ß-MnO2, and ZnO as microbial inhibitors on the antimicrobial efficiency in aqueous solution. These microbial inhibitors are fabricated in a diverse range of nanoscale hierarchical morphologies and geometrical shapes that have effective surface exposure, and well-defined 1D orientation. For instance, γ-Al2O3 H-NRs with 20 nm width and ˂0.5 µm length are grown dominantly in the [400] direction. The wurtzite structures of ß-MnO2 H-NRs with 30 nm width and 0.5-1 µm length are preferentially oriented in the [100] direction. Longitudinal H-NRs with a width of 40 nm and length of 1 µm are controlled with ZnO wurtzite structure and grown in [0001] direction. The antimicrobial efficiency of H-NRs was evaluated through experimental assays using a set of microorganisms (Gram-positive Staphylococcus aureus, Bacillus thuriginesis, and Bacillus subtilis) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. Minimal inhibitory and minimum bactericidal concentrations (MIC and MBC) were determined. These 1D H-NRs exhibited antibacterial activity against all the used strains. The active surface exposure sites of H-NRs play a key role in the strong interaction with the thiol units of vital bacterial enzymes, leading to microbial inactivation. Our finding indicates that the biological effect of the H-NR surface planes on microbial inhibition is decreased in the order of [400]-γ-Al2O3 > [100]-ß-MnO2 > [0001]-ZnO geometrics. The lowest key values including MIC (1.146 and 0.250 µg/mL), MBC (1.146, 0.313 µg/mL), and MIC/MFC (0.375 and 0.375 µg/mL) are achieved for [400]-plane γ-Al2O3 surfaces when tested against Gram-positive and -negative bacteria, respectively. Among the three H-NRs, the smallest diameter size and length, the largest surface area, and the active exposure [400] direction of γ-Al2O3 H-NRs could provide the highest microbial inactivation.


Subject(s)
Gram-Negative Bacteria , Manganese Compounds , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Microbial Viability , Oxides
16.
Nanotechnology ; 21(37): 375603, 2010 Sep 17.
Article in English | MEDLINE | ID: mdl-20720295

ABSTRACT

The development of nanofiltration systems would greatly assist in the production of well-defined particles and biomolecules with unique properties. We report a direct, simple synthesis of hexagonal silica nanotubes (NTs), which vertically aligned inside anodic alumina membranes (AAM) by means of a direct templating method of microemulsion phases with cationic surfactants. The direct approach was used as soft templates for predicting ordered assemblies of surfactant/silica composites through strong interactions within AAM pockets. Thus, densely packed NTs were successfully formed in the entirety of the AAM channels. These silica NTs were coated with layers of organic moieties to create a powerful technique for the ultrafine filtration. The resulting modified-silica NTs were chemically robust and showed affinity toward the transport of small molecular particles. The rigid silica NTs inside AAM channels had a pore diameter of

Subject(s)
Aluminum Oxide/chemistry , Filtration/instrumentation , Nanotechnology/instrumentation , Nanotubes/chemistry , Silicon Dioxide/chemistry , Cations/chemistry , Cytochromes c/isolation & purification , Emulsions/chemistry , Filtration/methods , Membranes, Artificial , Nanotechnology/methods , Nanotubes/ultrastructure , Porosity , Silicon Dioxide/chemical synthesis , Surface-Active Agents/chemistry
17.
Natl Sci Rev ; 7(5): 863-880, 2020 May.
Article in English | MEDLINE | ID: mdl-34692109

ABSTRACT

We report on low-cost fabrication and high-energy density of full-cell lithium-ion battery (LIB) models. Super-hierarchical electrode architectures of Li2SiO3/TiO2@nano-carbon anode (LSO.TO@nano-C) and high-voltage olivine LiMnPO4@nano-carbon cathode (LMPO@nano-C) are designed for half- and full-system LIB-CR2032 coin cell models. On the basis of primary architecture-power-driven LIB geometrics, the structure keys including three-dimensional (3D) modeling superhierarchy, multiscale micro/nano architectures and anisotropic surface heterogeneity affect the buildup design of anode/cathode LIB electrodes. Such hierarchical electrode surface topologies enable continuous in-/out-flow rates and fast transport pathways of Li+-ions during charge/discharge cycles. The stacked layer configurations of pouch LIB-types lead to excellent charge/discharge rate, and energy density of 237.6 Wh kg-1. As the most promising LIB-configurations, the high specific energy density of hierarchical pouch battery systems may improve energy storage for long-driving range of electric vehicles. Indeed, the anisotropic alignments of hierarchical electrode architectures in the large-scale LIBs provide proof of excellent capacity storage and outstanding durability and cyclability. The full-system LIB-CR2032 coin cell models maintain high specific capacity of ∼89.8% within a long-term life period of 2000 cycles, and average Coulombic efficiency of 99.8% at 1C rate for future configuration of LIB manufacturing and commercialization challenges.

18.
ACS Appl Bio Mater ; 3(12): 8496-8506, 2020 Dec 21.
Article in English | MEDLINE | ID: mdl-35019619

ABSTRACT

A highly sensitive protocol for signaling norepinephrine (NEP) in human fluids and neuronal cell line models should be established for clinical investigation of some neuronal diseases. A metal-free electrode catalyst was designed based on a sulfur-doped carbon spheroidal surface (S-CSN) and employed as a transducing element for selective signaling of NEP in biological samples. The designed electrode of S-CSN features a spherical construct and curvature surface to form a spheroidal nanolayer with an average layer size of <2 nm. S-CSN shows surface topography of a circular surface curvature with a rugged surface texture, ridge ends, and free open spaces between interlayers. The rich-space diversity surfaces offer highly active surface with facile molecular/electron diffusion, multi-diffusive centers, and high target loading along with in-/out-of-plane circular spheres of the S-CSN surface. The active doping of S atoms onto the carbon-based electrode creates an active transducing element with many active sites, strong binding to targeted molecules, facile diffusion of charges/molecules, long-term durability, and dense reactive exposure sites for signaling NEP at ultratrace levels. S-CSN could be a sensitive and selective nanosensor for signaling NEP and establishing a sensing protocol with high stability and reproducibility. The sensory protocol based on S-CSN exhibits high sensitivity and selectivity with a low detection limit of 0.001 µM and a wide linear range of 0.01-0.8 µM. The in vitro sensory protocol for NEP secreted from living cells (neuronal cell line model) under stimulated agents possesses high sensitivity, low cytotoxicity, and high biocompatibility. These results confirm the successful establishment of NEP sensor in human blood samples and neuronal cells for clinical investigation.

19.
J Mater Chem B ; 8(17): 3701-3732, 2020 05 06.
Article in English | MEDLINE | ID: mdl-32141469

ABSTRACT

Because of the environmental and economic casualties of biofouling on maritime navigation, modern studies have been devoted toward formulating advanced nanoscale composites in the controlled development of effective marine antifouling self-cleaning surfaces. Natural biomimetic surfaces have the advantages of micro-/nanoroughness and minimized free energy characteristics that can motivate the dynamic fabrication of superhydrophobic antifouling surfaces. This review provides an architectural panorama of the biomimetic antifouling designs and their key leverages to broaden horizons in the controlled fabrication of nanocomposite building blocks as force-driven marine antifouling models. As primary antifouling designs, understanding the key functions of surface geometry, heterogeneity, superhydrophobicity, and complexity of polymer/nanofiller composite building blocks on fouling-resistant systems is crucial. This review also discusses a wide range of fouling release coating systems that satisfy the growing demand in a sustainable future environment. For instance, the integration of block, segmented copolymer-based coatings and inorganic-organic hybrid nanofillers enhanced the model's antifouling properties with mechanical, superhydrophobic, chemically inert, and robust surfaces. These nanoscale antifouling systems offered surfaces with minimized free energy, micro-/nanoroughness, anisotropic heterogeneity, superior hydrophobicity, tunable non-wettability, antibacterial efficiency, and mechanical robustness. The confined fabrication of nanoscale orientation, configuration, arrangement, and direction along the architectural composite building blocks would yield excellent air-entrapping ability along the interfacial surface grooves and interfaces, which optimized the antifouling coating surfaces for long-term durability. This review provides systematic evidence of the effect of structurally folded nanocomposites, nanofiller tectonics, and building blocks on the creation of outstanding superhydrophobicity, self-cleaning surfaces, and potential antifouling coatings. The development of modern research gateways is a candidate for the sustainable future of antifouling coatings.


Subject(s)
Biofouling/prevention & control , Coated Materials, Biocompatible/pharmacology , Nanocomposites/chemistry , Animals , Coated Materials, Biocompatible/chemistry , Humans , Particle Size , Surface Properties
20.
J Colloid Interface Sci ; 319(2): 477-88, 2008 Mar 15.
Article in English | MEDLINE | ID: mdl-18178215

ABSTRACT

Design of nanocatalysts for efficient heterogeneous catalytic systems is needed to high ingredients for environmental cleanup of organic pollutant species. Here, well-defined order NiO-silica monolithic catalysts with hexagonal P6mm and cubic Pm3n mesostructures were successfully fabricated by using an instant direct-templating method of lyotropic and microemulsion phases of Brij 76 (C18H37(OCH2CH2)10 OH, C18EO 10). Ordered hexagonal P6mm NiO/HOM-2 monoliths could be fabricated in lyotropic system of Brij 76 at phase composition domains of TMOS/Brij 76 (50 wt%). However, periodically ordered cubic Pm3n NiO-supported monoliths were synthesized in microemulsion system formed by addition of C12-alkane to the hexagonal phase domains. This synthetic strategy also revealed that the NiO particles were well-dispersed into the silicate pore surface matrices of mesostructures. Monolithic NiO-silica composites with 2D hexagonal and 3D cubic geometries and with large particle morphologies show promise to act as catalysts. The current study revealed evidence of the advantages of nanoscale pore geometry and shape, and particle morphology of the supported silica monoliths in the design of nanocatalysts that can efficiently enhance the catalytic functionality in terms of stability, reversibility and reactivity. Furthermore, a key finding in our study was that 2D hexagonal and 3D cubic mesostructured NiO-silica catalysts retained the specific activity towards the oxidation reaction even after several regeneration/reuse cycles. Significant study of the mechanistic cyclization of the organic reactant using the density functional (DFT) calculations provided evidence of the key components of conformations of the functional model during the formation of the oxidation product.

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