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Search for "degradation" in Full Text gives 528 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Non-stoichiometric magnetite as catalyst for the photocatalytic degradation of phenol and 2,6-dibromo-4-methylphenol – a new approach in water treatment
Beilstein J. Nanotechnol. 2022, 13, 1531–1540, doi:10.3762/bjnano.13.126
- the organic compounds are discussed, as well as their influence on the degradation reaction rates. The degradation efficiency in photocatalytic processes was higher for DBMP (98%) than for phenol (approximately 50%). This proves the high efficiency of magnetite in the photocatalytic degradation of
- halogenated aromatic pollutants. The particularly high degradation efficiency regarding halogen-containing DBMP molecules and the yield of bromide ions indicate that DBMP degradation follows a mixed reduction–oxidation mechanism. DBMP molecules interact with the magnetite surface, enabling them to react with
- the available electrons, and, as a result, bromide ions can be released. The results confirm that magnetite is an effective photocatalyst in the degradation of halogenated aromatic pollutants. Keywords: magnetite; ozonolysis; persistent organic pollutants; photocatalysis; water treatment
In search of cytotoxic selectivity on cancer cells with biogenically synthesized Ag/AgCl nanoparticles
Beilstein J. Nanotechnol. 2022, 13, 1505–1519, doi:10.3762/bjnano.13.124
- weight loss curves and derivatives calculated from the thermogravimetric analysis data of the reaction products are shown in Figure 7a and Figure 7b, respectively. In the thermogram of the pineapple peel extract, denoted as PPeel extract, two stages of degradation of the metabolites were observed. The
- first degradation signal is very well defined and occurs at 202 °C, with an approximate mass loss of 35%. The second stage of degradation occurs in a temperature range of 277–395 °C, with an average temperature of 330 °C and an approximate mass loss of 15%. As the temperature increased, the sample
- continued to degrade such that at 750 °C, 36% of char residue remained (Table 2). In the thermograms of the reaction products, two stages of degradation are also shown, except for Ag/AgCl-T60, where a small additional peak appears at 163 °C, possibly from volatile organic molecules. The first degradation in
Orally administered docetaxel-loaded chitosan-decorated cationic PLGA nanoparticles for intestinal tumors: formulation, comprehensive in vitro characterization, and release kinetics
Beilstein J. Nanotechnol. 2022, 13, 1393–1407, doi:10.3762/bjnano.13.115
- -/microscale systems [25]. Chitosan is a natural biopolymer that is widely used in oral nanoparticulate formulations to provide increased drug concentration in the colon and to achieve improved therapy for the colon [26][27][28]. The degradation of chitosan occurs through the lysis of glycosidic bonds by the
LED-light-activated photocatalytic performance of metal-free carbon-modified hexagonal boron nitride towards degradation of methylene blue and phenol
Beilstein J. Nanotechnol. 2022, 13, 1380–1392, doi:10.3762/bjnano.13.114
- gas chromatograph coupled with a mass spectrometer (GC–MS, Thermo Fisher Scientific) by taking aliquots at 150 min and 330 min. The photocatalytic degradation and mineralization efficiencies were calculated by utilizing the following equations [19]: where Abs(0) symbolizes the initial absorbance, Abs
- modified boron nitride Photocatalytic study Figure 7a–g depicts the adsorption and photocatalytic degradation performance of MBN-80 towards MB (20 ppm) and phenol (10 ppm) accomplished through LED irradiation. Specifically, it removed 78.87% of MB (20 ppm solution) which was further enhanced to 93.83% in
- other hand, the photocatalytic degradation of phenol demonstrated a removal rate of 0.0015 min−1 with 48.56% removal and a mineralization efficiency of 20.17%. The AQE for phenol/H2O2 system was found to be at 2.67%. A negligible removal percentage in the order of 4% for MB and 6% for phenol over a
Recent trends in Bi-based nanomaterials: challenges, fabrication, enhancement techniques, and environmental applications
Beilstein J. Nanotechnol. 2022, 13, 1316–1336, doi:10.3762/bjnano.13.109
- photocatalysts in eco-friendly applications on a large scale. Bi-based nanomaterials as semiconductor photocatalysts are one of the study’s primary goals, as is the use of Bi-based nanomaterials for wastewater treatment, hydrogen generation, and photocatalytic degradation. Fabrication methods, reliability
- degradation, antibiotic treatment, and sterilization [38]. The term “advanced oxidation processes” has become more common recently. In this process, many oxidizing agents (∙OH) are created. Electron–hole pairs are formed in AOPs when the VB electrons of semiconductor photocatalysts are driven into the
- degradation, the most notable oxidizing species are •OH, photogenerated holes, and •O2−. These species are responsible for the photodegradation of organic and inorganic contaminants in wastewater [40]. To date, it is widely understood that the main limitation of photocatalysts is their low photocatalytic
Studies of probe tip materials by atomic force microscopy: a review
Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104
- . AFM probes based on these C–C composites' high aspect ratio tips produced highly high image resolution and good wear resistance, with no degradation of tip or image quality observed after 400 images had been acquired. Compared with the above composite probes, the combination with metal nanowires also
A super-oscillatory step-zoom metalens for visible light
Beilstein J. Nanotechnol. 2022, 13, 1220–1227, doi:10.3762/bjnano.13.101
- metasurface, which may lead to the degradation of the sub-diffraction focusing performance. The first is the phase modulation error due to discrete sampling. In the design, it is assumed that the physical size of the unit cell could be infinitely small for the convenience of optimization. In fact, a unit cell
- has a specific size and could only achieve a step-like discrete phase, which, in turn, deviates from the desired phase modulation. Second, the inhomogeneous amplitude modulation also contributes to performance degradation. In our design, it is assumed that only phase modulation with uniform amplitude
Rapid fabrication of MgO@g-C3N4 heterojunctions for photocatalytic nitric oxide removal
Beilstein J. Nanotechnol. 2022, 13, 1141–1154, doi:10.3762/bjnano.13.96
- photocatalytic activity of as-prepared MgO@g-C3N4 was evaluated by monitoring NO degradation. The photocatalytic NO removal experiments were performed using a 4.5 L reaction chamber and a Xenon lamp (300 W) as the visible light source. The initial NO concentration was 500 ppb, the flow rate was 1.5 L·min−1, and
- min. Trapping experiments were performed to evaluate the photocatalytic process mechanism for NO degradation. Three trapping agents were used representing different active species, namely isopropyl alcohol (IPA) for the hydroxyl radical (•OH), potassium dichromate (K2Cr2O7) for electrons (e−), and
- potassium iodide (KI) for holes (h+). The photocatalytic NO degradation experiments were performed under the previously described conditions. The photocatalytic NO degradation efficiency (η), the yield of NO2 conversion (γ), the apparent quantum efficiency (AQE, φ), and the DeNOx index (αDeNOX αDeNOx) were
Green synthesis of zinc oxide nanoparticles toward highly efficient photocatalysis and antibacterial application
Beilstein J. Nanotechnol. 2022, 13, 1108–1119, doi:10.3762/bjnano.13.94
- approach for the complete removal of organic pollutants due to their advantages. Semiconductors can act as catalysts for the complete degradation of organic substances when excited by light with an energy value higher than their bandgap. Among many semiconductors, TiO2 and ZnO are widely used as
- of 10 °C/min. The zeta potential was measured by analyzing 0.1 g of ZnO in 10 mL of water using a Malvern ZetasizerPro. The solid UV–vis DRS was carried out using a JASCO V550 UV–vis spectrometer. Photocatalytic degradation reaction The photocatalytic degradation of a dye solution under visible and
- centrifuged at 6000 rpm to measure the dye concentrations. The dye concentration was analyzed by UV–vis spectroscopy (Hitachi U2900) with maximum adsorption wavelengths of MB and MO of 664 nm and 464 nm, respectively [29][30]. The degradation efficiency was calculated using Equation 3. where c0 is the initial
Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications
Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93
- was 17.2% [29]. Grass was used as a natural source to prepare immensely photoluminescent N-CDs through a hydrothermal method. Six different dyes, that is, acid blue, acid red, eosin Y, eriochrome black T, methyl orange, and methylene blue underwent degradation in the presence of radiation, which
Biomimetic chitosan with biocomposite nanomaterials for bone tissue repair and regeneration
Beilstein J. Nanotechnol. 2022, 13, 1051–1067, doi:10.3762/bjnano.13.92
- phosphatase, bone morphogenic protein, runt-related transcription factor-2, bone sialoprotein, and osteocalcin. In vitro and in vivo studies highlight the scientific findings of antibacterial activity, tissue integration, stiffness, mechanical strength, and degradation behaviour of composite materials for
- bioimplants were placed and examined after four weeks of surgery. On the 14th day, histological studies revealed that cells had infiltrated into the holes. Meanwhile, degradation of the scaffold matrix was observed and represented as black spots in Figure 3 [107]. Chitosan with carbon nanomaterials for bone
- show degradation as well as bone mineral formation on the surface. The in vitro biological characteristics were tested using MC3T3-E1 cells, and the findings of adherence tests demonstrate osteoblastic cell adhesion to the coated surface at various time intervals [59] (Figure 5). According to Chen et
Spindle-like MIL101(Fe) decorated with Bi2O3 nanoparticles for enhanced degradation of chlortetracycline under visible-light irradiation
Beilstein J. Nanotechnol. 2022, 13, 1038–1050, doi:10.3762/bjnano.13.91
- -light irradiation. The obtained BOM-20 composite (20 wt % Bi2O3/MIL101(Fe)) exhibits the highest photocatalytic activity with CTC degradation efficiency of 88.2% within 120 min. The degradation rate constant of BOM-20 toward CTC is 0.01348 min−1, which is 5.9 and 4.3 times higher than that of pristine
- . The intermediate products were analyzed by liquid chromatography–mass spectrometry (LC–MS), and a possible photocatalytic degradation path of CTC was proposed. This work provides a new perspective for the preparation of efficient MOF-based photocatalysts. Keywords: Bi2O3; chlortetracycline; metal
- traditional measures were difficult to be popularized. Photocatalysis is considered as an alternative and promising strategy for degradation and mineralization of antibiotics due to its low cost, high efficiency, mild reaction condition, and no secondary pollution [9][10][11]. A variety of semiconductors have
Bioselectivity of silk protein-based materials and their bio-inspired applications
Beilstein J. Nanotechnol. 2022, 13, 902–921, doi:10.3762/bjnano.13.81
- materials using bioactive and bioadhesive molecules, such as full-length ECM proteins or functional peptide fragments thereof. These ligands interact with cell receptors for guiding cellular responses, such as cell proliferation or specific matrix degradation [31][32][33][34]. Compared to full-length
- biomaterials and medical devices with antifouling and antibacterial properties, but with reduced susceptibility to enzymatic degradation [85]. General advantages of AMPs/HDPs and mimicking polymer systems over antibiotics as a new generation of antimicrobial agents are their functional diversity, broad
- epidermis [126]. Strikingly, silk materials from silkworms and spiders share a set of highly interesting properties, including mechanical and chemical stability, biocompatibility for mammalian cells and tissues, persistence against microbial degradation and, moreover, potential microbe-repellent and
Solar-light-driven LaFexNi1−xO3 perovskite oxides for photocatalytic Fenton-like reaction to degrade organic pollutants
Beilstein J. Nanotechnol. 2022, 13, 882–895, doi:10.3762/bjnano.13.79
- decompose the methylene blue molecules. Accordingly, the synthesis condition of pH 0, calcination temperature at 700 °C, and Fe/Ni ratio = 7/3 could form LaFe0.7Ni0.3O3 perovskite oxides as highly efficient photocatalysts. Moreover, various conditions during the photocatalytic degradation were verified
- complexes might compete with the hydroxyl radicals, eliciting a degradation of the reaction performance [18]. In recent years, the Fenton method has gradually developed into a new scenario of oxidation method, called photo-Fenton, which is facilitated or driven by the light source. Compared with a typical
- degradation. Though it was proven that Mn-doped LaFeO3 could enhance the activity of heterogeneous photo-Fenton-like reactions, the influence of Mn content on the activity was not significant [30]. Phan et al. verified that Cu-doped LaFeO3 exhibited physicochemical properties to decolorize methlyorgane
Temperature and chemical effects on the interfacial energy between a Ga–In–Sn eutectic liquid alloy and nanoscopic asperities
Beilstein J. Nanotechnol. 2022, 13, 817–827, doi:10.3762/bjnano.13.72
- Au. For this reason, we assume that a small amount of gold dissolved in the metallic melt investigated here. However, the dissolution of Au should be small since it is thermally activated. In the current study, we could not observe any degradation of the Au tip nor measure traces of Au in liquid Ga
Gelatin nanoparticles with tunable mechanical properties: effect of crosslinking time and loading
Beilstein J. Nanotechnol. 2022, 13, 778–787, doi:10.3762/bjnano.13.68
- optimal treatment. Therefore, the characteristics of nanoparticles regarding mechanical properties, size, surface charge, surface composition, and degradation and drug release mechanisms must be considered during formulation development [1]. Except for the mechanical properties, the research activities do
- degradation of the particles using trypsin for 6 h. The results revealed a crosslinking-dependent loading, with increased FITC-dextran loading for a longer crosslinking. The initial incorporation of FITC-dextran had a significant influence on Young’s moduli. The correlation between Young’s moduli and the
- loading of FITC-dextran was determined by dissolving the gelatin network using enzymatic degradation. The fluorescence intensity of the resulting solution was measured [18]. Therefore, 5 mg of freeze-dried GNPs were dispersed in 5 mL PBS containing 2.5 mg trypsin at room temperature. After 6 h of
Hierarchical Bi2WO6/TiO2-nanotube composites derived from natural cellulose for visible-light photocatalytic treatment of pollutants
Beilstein J. Nanotechnol. 2022, 13, 745–762, doi:10.3762/bjnano.13.66
- nanotubes were formed by TiO2 nanotubes that uniformly anchored with Bi2WO6 nanoparticles of various densities on the surface. The composites exhibited improved photocatalytic activities toward the reduction of Cr(VI) and degradation of rhodamine B under visible light (λ > 420 nm), which were attributed to
- photocatalytic reduction of Cr(VI), while hydroxyl radicals and reactive holes contributed to the photocatalytic degradation of rhodamine B. Keywords: biomimetic synthesis; cellulose; nanoarchitectonics; nanocomposite; nanotubes; photocatalysis; pollutants; Introduction The direct emission of untreated
- some Bi2WO6/TiO2 composites, which were employed in various photocatalytic applications, such as degradation of organic pollutants [25], oxidation of methane [24], and production of hydrogen by water splitting [26]. According to these reports, Bi2WO6/TiO2 composites have better photocatalytic
Sodium doping in brookite TiO2 enhances its photocatalytic activity
Beilstein J. Nanotechnol. 2022, 13, 599–609, doi:10.3762/bjnano.13.52
- exceeded four times that of P25 under visible light irradiation [8]. The degradation of methyl orange by brookite nanoflowers was much more efficient than that by anatase nanorods [9]. Moreover, the heterojunction of brookite TiO2 can enhance the photocatalytic activity (e.g., the rutile/brookite TiO2
- heterojunction exhibited a synergetic effect, improving the photocatalytic activity for both hydrogen generation and organic dye degradation [10][11]). Similarly, the anatase/brookite heterojunction (38.2% brookite) also exhibited the highest degradation efficiency of cylindrospermopsin under UV–vis light [12
- performance of brookite mainly depends on the details of the preparation method and heat treatment used. For example, brookite TiO2 prepared from a Ti–EDTA complex exhibits a considerably higher activity for the degradation of NO than that synthesized from the titanate–glycolate complex [19]. The
Stimuli-responsive polypeptide nanogels for trypsin inhibition
Beilstein J. Nanotechnol. 2022, 13, 538–548, doi:10.3762/bjnano.13.45
- short in vivo half-lives, chemical instability, and high susceptibility to degradation [6]. Delivery systems represented by various polymer particles provide necessary and effective protection of bioactive cargo against degradation and elimination as well as for prolonged circulation time. Nanogels
Ciprofloxacin-loaded dissolving polymeric microneedles as a potential therapeutic for the treatment of S. aureus skin infections
Beilstein J. Nanotechnol. 2022, 13, 517–527, doi:10.3762/bjnano.13.43
- low bioavailability of orally administered drugs due to poor absorption and enzymatic degradation in the gastrointestinal tract [3][4]. Among the different types of microneedles, dissolving microneedles have attracted research due to their advantages, which include low cost and simple preparation
- . aureus skin infections was investigated. Recent studies showed that dissolving polymeric microneedles are a promising approach in topical and transdermal drug delivery because of the rapid dissolution and/or degradation of the polymer, which, in turn, releases the incorporated drug [18]. These dissolving
Ethosomal (−)-epigallocatechin-3-gallate as a novel approach to enhance antioxidant, anti-collagenase and anti-elastase effects
Beilstein J. Nanotechnol. 2022, 13, 491–502, doi:10.3762/bjnano.13.41
- peroxides and free oxygen radicals increase. Damage to phospholipids, which contain large amounts of unsaturated fatty acids and are sensitive to degradation by hydroxyl radicals, deteriorates the structure of the cell membrane [3]. Antioxidants are compounds that capture and stabilize free radicals and
- neurodegenerative disorders [7][8][9]. However, there are some difficulties in the formulation of EGCG such as the first pass metabolism effect, enzymatic degradation, and low bioavailability [8][10]. Skin delivery, besides being painless and noninvasive, has many advantages such as controlled drug delivery
- were determined and degradation kinetics profiles were obtained (Figure 3 and Figure 4, respectively). As seen in Figure 4, EGCG degradation was found to show first-order kinetics for ETHs. The degradation of EGCG in suspended ETHs was slower and lower at 4 °C compared to its degradation at 25 °C. No
Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review
Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40
- when used as a SERS substrate. The self-cleaning ability of ZnO alone or ZnO–noble metal-based nanostructured substrates has been shown under UV or visible irradiation via the photocatalytic degradation of the organic molecules attached to the substrate [8][34][53]. For instance, [75] presented Au
- -coated roughened ZnO nanostructures, which enabled photocatalytic degradation of adsorbed analytes and the reuse of the substrate. Also, [73] demonstrated the self-cleaning ability of ZnO–Au nanostructures under UV irradiation. The rhodamine 6G adsorbed on Ag–ZnO–Au film showed a fast photocatalytic
- degradation due to higher surface area and the presence of a metal–semiconductor junction by this 3D hybrid structure [68]. Additionally, it was observed that metal-based substrates did not exhibit any catalytic degradation, while those that incorporated ZnO led to a significant decrease in the SERS intensity
A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures
Beilstein J. Nanotechnol. 2022, 13, 424–436, doi:10.3762/bjnano.13.35
- environmental conditions (20 °C, 40% relative humidity) for one week, the signal level remained at 95% of the initial value. For samples stored under environmental conditions for a month, the signal level remained at 90% of the initial value. The influence of the environment and degree of sample degradation can
Micro- and nanotechnology in biomedical engineering for cartilage tissue regeneration in osteoarthritis
Beilstein J. Nanotechnol. 2022, 13, 363–389, doi:10.3762/bjnano.13.31
- slow and plays a critical role in cartilage functionality and homeostasis. Therefore, any degradation would result in the damage and failure of cartilage to withstand mechanical loads. Hyaluronic acid (HA) is an unbranched polysaccharide with a high molecular weight, which plays a major role in
- molecules and to provide protection for these molecules from physiological degradation. NPs are expected to control the release profile of the incorporated agent, decrease the severity of the side effects of these drugs, and maximize the effect of the bioactive agent through its safe delivery to target
- for cartilage tissue regeneration because it can respond to external magnetic fields and specifically relocate to the defective cartilage to resurface the injured site [62]. Initial OA is a slow, complex process characterized by the inflammation and subsequent production of cartilage degradation
Coordination-assembled myricetin nanoarchitectonics for sustainably scavenging free radicals
Beilstein J. Nanotechnol. 2022, 13, 284–291, doi:10.3762/bjnano.13.23
- phosphopeptides, exhibited huge therapeutic potential in antioxidant treatments [11][12][13]. Nevertheless, a plenty of disadvantages restrict biomedical applications, namely low biocompatibility of the metal-based nanomaterials, low bioavailability of hydrophobic small-molecule compounds, and easy degradation of
- , and allergens [17]. In spite of the tremendous potential, Myr possesses the same shortcomings as many hydrophobic small molecules, namely low bioavailability, poor water solubility and rapid degradation at pH > 6.8, which limits its clinical therapeutic potential [22]. GSH consists of glycine
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