Greater Surface Area Research Articles

Nanostructured proteins for delivering drugs to diseased tissues

During the last few years, nanostructures based on proteins have been playing a vital role in revolutionizing the nanomedicine era. Since protein nanoparticles are smaller and have a greater surface area, they retain a better capacity to interact with other molecules, resulting in carrying payloads efficiently to diseased tissues. Besides having attractive biocompatibility and biodegradability, protein nanoparticles can also be modified on their surfaces. For the fabrication of these nanostructures, there are several processes involved, including emulsification, desolvation, a combination of complex coacervation and electrospray. This can be achieved by using different proteins such as albumin, gelatin, elastin, gliadin, collagen, legumin and zein, as well as a combination of these proteins. It is possible to functionalize protein nanoparticles by altering their internal and external interfaces so that they can encapsulate drugs, release them in a controlled manner, disassemble them systematically and target tumors. This review highlights the physicochemical properties and engineering of several proteins to nano-dimensions used to deliver drugs to diseased tissues.

Effects of Root Growth of Deep and Shallow Rooting Rice Cultivars in Compacted Paddy Soils on Subsequent Rice Growth

Rice is often grown as multiple seasons in one year, alternating between flooded and upland systems. A major constraint, introduced from the flooded system, is a plough pan that may decrease rooting depth and productivity of follow-on upland rice. Roots penetrating the plough pan under flooded rice system can leave a legacy of weaker root growth pathways. Deeper rooting rice cultivars could have a bigger impact, but no direct evidence is available. To explore whether a deep rather than a shallow rooting rice cultivar grown in a flooded cropping cycle benefited deeper root growth of follow-on rice in an upland, reduced tillage cropping cycle, a simulated flooded paddy in greenhouse was planted with deep (Black Gora) and shallow (IR64) rooting cultivars and a plant-free control. Artificial plough pans were made in between the topsoil and subsoil to form different treatments with no plough pan (0.35 MPa), soft plough pan (1.03 MPa) and hard plough pan (1.70 MPa). After harvest of this ‘first season’ rice, the soil was drained and undisturbed to simulate zero-tillage upland and planted rice cultivar BRRI Dhan 28. The overall root length density (RLD), root surface area, the numbers of root tips and branching of BRRI Dhan 28 did not vary between plough pan and no plough pan treatments. Compared with the shallow rooting rice genotype, the deep rooting rice genotype as ‘first season’ crop produced 19% greater RLD, 34% greater surface area and 29% more branching of BRRI Dhan 28 in the subsoil. In the topsoil, however, BRRI Dhan 28 had 28% greater RLD, 35% greater surface area and 43% more branching for the shallow rather than deep rooting genotype planted in the ‘first season’. The results suggested that rice cultivar selection for a paddy cycle affects root growth of a follow-on rice crop grown under no-till, with benefits to subsoil access from deep rooting cultivars and topsoil proliferation for shallow rooting cultivars.

In situ constructing Co/Co-Ox/Co-Nx diverse active sites on hollow porous carbon spheres derived from Co-MOF for efficient bifunctional electrocatalysis in rechargeable Zn-air

Earth-rich, durable, and efficient bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is vitally important for the wide application of zinc-air batteries in the future. However, due to the single active site, traditional commercial benchmark catalysts typically exhibit selective activity in only one of the two reactions (ORR or OER), making it difficult to meet the dual functional catalytic requirements. Developing efficient oxygen electrocatalysts that achieve diverse active sites on a single catalyst and understanding their internal synergistic reaction activity remain a challenge. Herein, spherical hollow porous carbon matrix composites (s-Co/CoNC) with the coexistence of diverse intrinsic active sites including Co-Nx and Co-Ox species and metal Co nanoparticles were prepared by pyrolysis with oxygen-enriched Co-MOFs as precursor in the presence of melamine. Owing to the combined advantages of the catalyst including the great specific surface area, good conductivity, abundant diverse intrinsic active sites towards ORR and OER, and the electronic interaction among active sites and the optimized the adsorption/desorption process of oxygen species at the catalyst surface, s-Co/CoNC exhibits desirable electrocatalytic activity for both ORR and OER with an ORR half-wave potential of 0.81 V, an OER potential of 1.53 V(vs. RHE at 10 mA cm−2), providing a small reversible potential difference of 0.72 V, superior to the commercial noble-metal catalysts and the most reported cobalt based ORR/OER catalysts. The assembled s-Co/CoC-based rechargeable Zn-air batteries possess high peak power density of 101.7 mW cm−2. This work provides a significant strategy for constructing high-performance dual functional catalysts for secondary Zn-air batteries.

Synthesis of a novel graphene oxide/belite cement composite and its effects on flexural strength and interfacial transition zone of ordinary portland cement mortars

In order to address the size mismatch between nanoscale graphene oxide and micron-scale ordinary portland cement (OPC), a novel graphene oxide/belite cement (GO/BC) composite hydrated for different periods was synthesized and applied to OPC-based mortar specimens. The morphology, surface area and pore size distributions of hydrated GO/BC composites were characterized. Thermogravimetric analyses and X-ray photoelectron spectroscopy (XPS) test were carried out to investigate the relative amount of different phase assemblages in the composite and possible chemical interactions between graphene oxide and belite cement, respectively. Moreover, the effects of GO/BC composite addition on the flexural strength, the porosity and thickness of ITZ in the OPC-based mortars were examined. Experimental results showed that the GO/BC composite after 14 and 21 days of curing exhibited some flower-like hydration products with ‘petals’ sizing around several microns and a large surface area. The hydrated GO/BC composite after 14 and 28 days, for 14-day in particular, is more effective in elevating the flexural strength and densifying the ITZ region of OPC-based binders, compared to the graphene oxide or belite cement alone. Thus, hydrated GO/BC composites could be served as a better nucleation seed for promoting the hydration of OPC due probably to their greater surface area, suitable sizes and chemical interactions between graphene oxide and belite cement.

Removal of methylene blue by porous biochar obtained by KOH activation from bamboo biochar

A series of activated biochar (KBBC-700, KBBC-800 and KBBC-900) which were modified by KOH and pyrolysis at various temperatures from ball-milling bamboo powder were obtained. The physicochemical properties and pore structures of activated biochar were investigated by scanning electron microscopy (SEM), fourier transform infrared spectoscopy (FT-IR), X-ray diffraction (XRD) and N2 adsorption/desorption. The adsorption performance for the removal of methylene blue (MB) was deeply studied. The results showed that KBBC-900 obtained at activation temperature of 900 °C exhibited a great surface area which reached 562 m2/g with 0.460 cm3/g of total pore volume. The enhancement of adsorption capacity could be ascribed to the increase of surface oxygen-containing functional groups, aromatization and mesoporous channels. The adsorption capacity was up to 67.46 mg/g under the optimum adsorption parameters with 2 g/L of adsorbent dose, 11 of initial solution pH and 298 K of the reactive temperature. The adsorption capacity was 70.63% of the first time after the material was recycled for three cycles. The kinetics indicated that the adsorption equilibrium time for MB on KBBC-900 was of about 20 min with the data fitted better to the pseudo-second-order kinetics model. The adsorption process was mainly dominated by chemical adsorption. Meanwhile, the adsorption isotherm showed that the Langmuir model fitted the best, and thermodynamic parameters revealed that the adsorption reaction was the endothermic nature and the spontaneous process. Adsorption of MB mainly attributed to electrostatic interactions, cation-π electron interaction and redox reaction. This study suggested that the activated biochar obtained by KOH activation from bamboo biochar has great potentials in the practical application to remove MB from wastewater. Graphical

Mesoporous carbon-based sensor for quantification of prasugrel in solubilized system

In this study, a mesoporous carbon-based electrochemical sensor has been made up, possessing the novelty for ultra-sensitive detecting Prasugrel in pharmaceutical formulation and biological samples. Mesoporous carbon has even and tunable pore size, greater surface area, with excellent, electrical conductivity, wide availability and also have unique surface functionalization properties which make them significant sensing material now a days. Determination of prasugrel was accomplished with mesoporous carbon/GCE sensor on square-wave and cyclic voltammetry. Effects of various environmental and instrumental parameters like effect of buffer, casting volume, solvent, and pH on peak signal have been optimized. The best results were obtained in 0.1% cetyltrimethylammonium bromide - aqueous 0.1 M potassium chloride–phosphate buffer (pH 5.3). The limit of detection and quantification of the pure drug was found to be 37.0 ng mL−1 and 110.0 ng mL−1 (with the correlation coefficient, r = 0.988 and the standard deviation, (S.D.) = 0.6 (n = 6), respectively. The fabricated sensor was efficaciously validated by the determination of the drug in pharmaceutical formulation. Recoveries obtained were 97.84–99.37%.

Responses of syntrophic microbial communities and their interactions with polystyrene nanoplastics in a microbial electrolysis cell

Microbial electrochemical technologies are promising for simultaneous energy recovery and wastewater treatment. Although the inhibitory effects of emerging pollutants, particularly micro/nanoplastics (MPs/NPs), on conventional wastewater systems have been extensively studied, the current understanding of their impact on microbial electrochemical systems is still quite limited. Microplastics are plastic particles ranging from 1 μm to 5 mm. However, nanoplastics are smaller plastic particles ranging from 1 to 100 nm. Due to their smaller size and greater surface area, they can penetrate deeper into biofilm structures and cell membranes, potentially disrupting their integrity and leading to changes in biofilm composition and function. This study first reports the impact of polystyrene nanoplastics (PsNPs) on syntrophic anode microbial communities in a microbial electrolysis cell. Low concentrations of PsNPs (50 and 250 μg/L) had a minimal impact on current density and hydrogen production. However, 500 μg/L of PsNPs decreased the maximum current density and specific hydrogen production rate by ∼43 % and ∼48 %, respectively. Exposure to PsNPs increased extracellular polymeric substance (EPS) levels, with a higher ratio of carbohydrates to proteins, suggesting a potential defense mechanism through EPS secretion. The downregulation of genes associated with extracellular electron transfer was observed at 500 μg/L of PsNPs. Furthermore, the detrimental impact of 500 μg/L PsNPs on the microbiome was evident from the decrease in 16S rRNA gene copies, microbial diversity, richness, and relative abundances of key electroactive and fermentative bacteria. For the first time, this study presents the inhibitory threshold of any NPs on syntrophic electroactive biofilms within a microbial electrochemical system.

The effects of sheet and network solid structures of similar TPMS scaffold architectures on permeability, wall shear stress, and velocity: A CFD analysis.

Triply periodic minimal surface (TPMS) is known mathematically as a surface with mean curvature of zero and replicated in three directions infinitely. Providing the pore combination in porous structures with surface connections, they provide large surface areas. This study aims to determine the effects of the network solid and sheet solid structures in the three different TPMS architectures on bone regeneration. Evaluation is made for Diamond, Gyroid, and I-WP structures, which are widely preferred architectures in terms of mechanical strength. Scaffolds are modeled as both network solid and sheet solid unit cells with similar porosities (60%, 70%, and 80%). Flow analyses are performed with the Computational Fluid Dynamics method to determine of potential for bone cell development of scaffolds. The permeability, wall shear stress on the surfaces, and the flow velocity distribution of the scaffolds are obtained with these analyses. The permeability value of 18 scaffolds is between the permeability values determined for trabecular bone. The permeability of network solid TPMS scaffolds for the same architectures is higher than sheet solid TPMS scaffolds due to the low pressures generated. The maximum wall shear stress in scaffolds decreases as porosity increases. Since the maximum wall shear stresses occur in less than 0.1% area on the scaffold surfaces, it is more appropriate to examine distribution of these stresses on the scaffold surfaces. Sheet solid structures within TPMS are more advantageous for biomechanical environments due to their greater surface area at similar porosities, wall shear stress, and permeability values.

Controlled synthesis of samarium trifluoride nanoparticles in a water-in-oil microemulsion: Effects of water-to-surfactant ratio on particles and phosphate removal

SmF3 nanoparticles with a hexagonal closed pack structure were synthesised by W/O microemulsions of water/Tween 20/1-butanol/toluene. The crystal structure, composition and purity of the sample, as well as the morphology of the produced nanoparticles were studied using Powder X-ray Diffraction, Energy Dispersive X-ray, elemental mapping, Transmission Electron Microscope and Field Emission Scanning Electron Microscope. According to Dynamic Light Scattering study, particle size distribution is governed by the water to surfactant mole ratio (W0), and increasing W0 causes an increase in particle size distribution (PSD). PSD of SmF3 nanoparticles produced at W0 = 50 is the widest compared to W0 = 10. W/O microemulsion method provides formed nanoparticles to attain a spherical form at both W0. The so formed nanoparticles can adsorb phosphate ions from aqueous solution via electrostatic interactions, and their adsorption effectiveness is dependent on particle size and surface area. Small sized nanoparticles, at W0 = 10 removed 98.5% of the phosphate because of its greater surface area while the comparatively larger nanoparticle at W0 = 50 removed 84.5% of the phosphate. The adsorption kinetic data for both W0 are better fitted by pseudo second order model than by pseudo first order model and the calculated equilibrium adsorption capacities is higher for W0 = 10 than for 50. Consequently, this approach yields the most cost effective pure synthesis of high-cost, size and shape controlled rare earth nanoparticles and therefore used in size dependent applied field.

Development of niobium doped tin oxide nanostructure via hydrothermal route for photocatalytic degradation of methylene blue and antimicrobial study

In this work, we discuss the effect of niobium (Nb) doping concentrations of 2% and 4% on the physicochemical characteristics and photocatalytic properties of tin dioxide nanostructure, which were successfully developed by a basic hydrothermal route. Nb-doped SnO2 were characterized with regards to their optical, structural and photocatalytic features. X-ray diffraction (XRD) analyses display that both pristine and doped tin dioxide had a fine crystalline structure having tetragonal structure. Scanning electron microscopy (SEM) analysis shows that materials exhibited the irregular shaped nanoparticles morphology. Optical absorption analysis using UV–visible spectroscopy revealed a redshift in the bandgap energy for Nb3+ doped SnO2 nanoparticles. Methylene blue aqueous (MB) dye was degraded by 93.78% in 120 min when exposed to 4% Nb doped SnO2 NPs under visible light. The 4% Nb doped SnO2 shows elevated photocatalytic activity owing to their greater surface area containing greater active zones responsible for adsorption of larger dye species and good structural stability. Similarly, the 4% Nb doped SnO2 photocatalysts maintained their excellent stability and photodegradation efficiency over 89% even after being subjected to 5th cycles. The scavenger analysis demonstrates that the superoxide (O2) radical, a major active substance, performed a crucial role in the mineralization of the aqueous MB dye. The 4% Nb doped SnO2 also shows remarkable antimicrobial activity. Our finding suggests that doping strategy considered as efficient method that can help to increase the photocatalytic and antimicrobial activity.

Propionic acid-based additive with surfactant action on the feeding value of rehydrated corn grain silage for dairy cows performance

Eighteen Holstein cows with 218 ± 106 days in milk (mean ± SD) and average daily milk yield of 22 ± 7.6 kg (mean ± SD) were assigned to six 3 × 3 Latin squares to evaluate the effects of using a propionic acid-based additive with surfactant action (Mycoflake™; Kemin South America, Indaiatuba, SP, Brazil) at the ensiling of rehydrated corn grain on its nutritional value and animal performance. Dry ground corn grain (998 μm) was rehydrated to reach 400 g/kg fresh matter of moisture, with or without the additive, and ensiled in 200-L plastic drums. Treatments were prepared as follows: rehydrated corn grain silage (RCGS) stored for 30 d as a negative control (30CON), RCGS stored for 60 d as a positive control (60CON) and RCGS treated with Mycoflake™ at 2 L/t and stored for 30 d (30MYC). The animals were offered a total mixed ration containing 399 g/kg whole-plant corn silage, 98 g/kg Tifton haylage, 207 g/kg RCGS (according to treatment), 98 g/kg citrus pulp, 173 g/kg soybean meal and 25 g/kg mineral-vitamin mix in total diet dry matter (DM). Ruminal DM disappearance (DMD) of RCGS was evaluated in situ using two canulated Holstein cows after 12, 24 and 48 h of incubation. Total tract apparent digestibility (TTAD) of nutrients was determined using the indigestible neutral detergent fiber content as a marker measured after 288 h of incubation in a canulated Holstein cow. Although no change in soluble protein content was observed for the 30MYC silage, its NH3-N content was greater than 30CON in both DM (P = 0.01) and total N (P = 0.02) basis, and did not differ from 60CON. The proportion of NH3-N in soluble N of 30MYC was the highest compared to both 30CON (P = 0.02) and 60CON (P < 0.01). The 30MYC RCGS presented lower geometric mean particle size and greater surface area than both 30CON (P < 0.01) and 60CON (P < 0.01). Although the pH of 30MYC RCGS did not differ from 30CON and 60CON, its lactic acid content (11.9 g/kg DM) was greater than both 30CON (9.28 g/kg DM; P = 0.05) and 60CON (8.10 g/kg DM; P = 0.01). No changes in ruminal DMD were observed for 30MYC RCGS against 30CON. There were no changes on dairy cows performance fed the 30MYC RCGS against 30CON. Cows fed 30MYC RCGS presented a different pattern of sorting behavior against 30CON and 60CON, resulting in lower intake of physically effective fiber than both 30CON (P = 0.01) and 60CON (P = 0.02), although no effect on ruminating and chewing activities was observed. No effect on TTAD of nutrients was observed for cows fed 30MYC RCGS against 30CON. Mycoflake™ hampered the formation of aggregates in RCGS, and did not enhance proteolysis. Despite changes in sorting behavior, the additive did not affect performance of dairy cows.

A review on biochar’s effect on soil properties and crop growth

Intensive cultivation of agricultural soils causes soil degradation which emphasizes the need for sustainable soil management. Biochar, a pyrolysed carbon rich material has gained great interests among the researchers because of its eco-friendly benefits in addition to soil quality enhancement. Reviews on biochar, mainly confined to its environmental benefits like carbon sequestration and climate change. In this review, we summarize i) the effect of biochar application on soil properties (physical, chemical, biological), ii) remediation potential of biochar in heavy metal contaminated soils and iii) its impact on crop productivity. The properties of biochar like pH, greater surface area, cation exchange capacity, and nutrient content positively influences the soil properties and ultimately improves the soil fertility. Their effectiveness depends on biochar type, its dosage, soil type, etc. General trends from this review indicated that biochar as an effective amendment in acid soils than the alkaline or calcareous soils. Furthermore, the biochar effects are studied mostly under controlled conditions in laboratory, which needs to be validated under field conditions having varied soil types and agro-climatic zones.

Unraveling ultrasonic assisted aqueous-phase one-step synthesis of porous PtPdCu nanodendrites for methanol oxidation with a CO-poisoning tolerance

The tailored design of tri-metallic Pt-based porous nanodendrites (PNDs) is crucial for green energy production technologies, ascribed to their fancy features, great surface areas, accessible active sites, and stability against aggregation. However, their aqueous-phase one-step synthesis at room temperature remains a daunting challenge. Herein, we present a facile, green, and template-free approach for the one-step synthesis of PtPdCu PNDs by ultrasonication of an aqueous solution of metal salts and Pluronic F127 at 25 ℃, based on natural isolation among nucleation and growth step driven by the disparate reduction kinetics of the metals and acoustic cavitation mechanism of ultrasonic waves. The resultant PtPdCu PNDs formed in a spatial nanodendritic shape with a dense array of branches, open corners, interconnected pores, high surface area (46.9 m2/g), and high Cu content (21 %). The methanol oxidation reaction (MOR) mass activity of PtPdCu PNDs (3.66 mA/µgPt) is 1.45, 2.73, and 2.83 times higher than those of PtPd PNDs, PtCu PNDs, and commercial Pt/C, respectively based on equivalent Pt mass, which is superior to previous PtPdCu catalysts reported elsewhere, besides a superior durability and CO-poisoning tolerance. This study may pave the way for the controlled fabrication of ternary Pt-based PNDs for various electrocatalytic applications.

Synthesis and Photocatalytic Activity of Si-doped TiO2 Nanotube/SnS Hybrids for Environmental Decontamination

Background: Heterostructures with nanoscale sizes have great superiorities in photocatalytic environment decontaminant because of their efficient interface charge transfer and great surface area. Objective: This work reports the facile fabrication of nano-tubular TiO2 and Si-doped TiO2 (NTs) hybridizing SnS nanocrystallites and their high-efficient photocatalytic activity. Methods: The modified hydrothermal processes were used to synthesize the nanotubes. A chemical bath deposition process was used to hybridize SnS nanocrystallines with the nanotubes. Results: The fabricated nanostructures show wide light absorption in the UV-visible region. The SBET, light absorption, hydrophilicity, and photo-induced super hydrophilicity were enhanced by Si-doping and SnS modification. Moreover, high-efficient interface charge transfer was produced after the SnS modification and further enhanced by the Si doping because of band structure modulation. Conclusion: Thus, the Si-doped TiO2 nanotubes/SnS heterostructures showed remarkably enhanced photocatalytic and Fenton-like photocatalytic activity in dye wastewater treatment than the TiO2 NTs. This work suggests potential materials and their facile fabrication process for the photocatalytic application of environmental decontamination.

Recent Advances in the Pharmaceutical and Biomedical Applications of Cyclodextrin-Capped Gold Nanoparticles.

The real problem in pharmaceutical preparation is drugs' poor aqueous solubility, low permeability through biological membranes, and short biological t1/2. Conventional drug delivery systems are not able to overcome these problems. However, cyclodextrins (CDs) and their derivatives can solve these challenges. This article aims to summarize and review the history, properties, and different applications of cyclodextrins, especially the ability of inclusion complex formation. It also refers to the effects of cyclodextrin on drug solubility, bioavailability, and stability. Moreover, it focuses on preparing and applying gold nanoparticles (AuNPs) as novel drug delivery systems. It also studies the uses and effects of cyclodextrins in this field as novel drug carriers and targeting devices. The system formulated from AuNPs linked with CD molecules combines the advantages of both CD and AuNPs. Cyclodextrins benefit in increasing aqueous drug solubility, loading capacity, stability, and size control of gold NPs. Also, AuNPs are applied as diagnostic and therapeutic agents because of their unique chemical properties. Plus, AuNPs possess several advantages such as ease of detection, targeted and selective drug delivery, greater surface area, high loading efficiency, and higher stability than microparticles. In the present article, we tried to present the potential pharmaceutical applications of CD-derived AuNPs in biomedical applications including antibacterial, anticancer, gene-drug delivery, and various targeted drug delivery applications. Also, the article highlighted the role of CDs in the preparation and improvement of catalytic enzymes, the formation of self-assembling molecular print boards, the fabrication of supramolecular functionalized electrodes, and biosensors formation.

Multifunctional immunosensors based on mesoporous silica nanomaterials as efficient sensing platforms in biomedical and food safety analysis: A review of current status and emerging applications

Over the last few years, the progress of biosensing has revolutionized the dynamic domain of medical and food safety analysis. Among various factors, the role of materials and nanomaterials in terms of development biosensors is undeniable. Mesoporous silica nanomaterials as an inseparable and vital part of novel analytical approaches can improve their properties. Elaborately, the unique physiochemical properties including great surface area, tunable nanometer-scale pore sizes and ease of substrate modification can make these materials excellent candidates for biosensing. In addition, adding antibodies to the structure of biosensors based on mesoporous silica nanomaterials can boon the selectivity and sensitivity of these biosensing platforms. To illustrate, the specificity and sensitivity of the antigen-antibody interaction improved the feature of these types of biosensors for selective quantification of numerous targets including viruses, biomarkers, bacterial infections cells and bacteria. In this study, we attempted to review the latest advancement of immunoassays based on mesoporous silica nanomaterials which operate according to electrochemical, optical and electrochemiluminescence techniques in the field of food safety and biomedical analysis. In addition, this study can open new windows for exploiting competent sensing methods as laboratory tools by addressing the current challenges and future perspectives. To elaborate, these sensing approaches should evolve for point-of-care analysis and be designed outside of controlled environments using real-life samples with minimal user involvement.

Preparation and performance of NaTaO3/TiO2 humidity sensors with high responsivity

In this study, a high-performance nanocomposite NaTaO3/TiO2 humidity sensor was prepared using the hot solvent method, and its humidity sensitivity was analysed. Structural analysis indicated that the NaTaO3/TiO2 composite had a greater surface area than pristine NaTaO3. Consequently, the surface of the NaTaO3/TiO2 composite adsorbed more water molecules, resulting in enhanced humidity response. During the preparation of the composite, Ti3+ and oxygen vacancy defects formed in the NaTaO3/TiO2 composites, which contributed to the adsorption and desorption of water molecules. The Ti3+ and oxygen vacancies promoted the generation of H3O+ ions and shortened the response and recovery time of the NaTaO3/TiO2 sensor. Compared with the NaTaO3 or TiO2 individually, the aforementioned properties of the composite materials endow the sensor with superior humidity sensitivity performance. The NaTaO3/TiO2 humidity sensor exhibited impedance change over 4.5 orders of magnitude, high responsiveness (4011588%), lower hysteresis (8.5%), long-term stability, and response and recovery time (13 s and 9 s, respectively) in the relative humidity range of 11 to 95%. In addition, the complex impedance spectrum was analysed to elucidate the sensing mechanism. The preparation of the NaTaO3/TiO2 composite material provides a new direction for designing a high-sensitivity humidity monitoring resistance sensor based on NaTaO3.

Synthesis, Characterization and Mechanism of MnFe2O4@g-C3N4 Nanocomposite as an effective Photocatalyst for the Generation of Hydrogen and organic contamination degradation

Photocatalysis has recently been shown to be a good way to get rid of pollutants and produce hydrogen. MnFe2O4@g-C3N4 was synthesized by solid state synthesis technique. In addition to producing hydrogen, MnFe2O4@g-C3N4 demonstrated outstanding photocatalytic performance for the decay of pesticides under visible illumination. The morphology and structure of MnFe2O4@g-C3N4 were approved using Scanning Electron Microscopes (SEM), X-ray diffraction (XRD). Morover, Fourier transform infrared spectroscopy (FT-IR), UV–vis DRS, and surface area (BET). Based on the degradation of the carbaryl contaminant, the photocatalytic action of MnFe2O4@g-C3N4 was evaluated (94%). We for the first time could generate hydrogen by MnFe2O4@g-C3N4 and develop its photocatalytic activities by expanding the surface area and narrowing the band gap value (1.7 eV) and a great surface area of 53.46 m2/g, as displayed by the outcomes.

Adsorption of Metformin on Graphene Nanoribbons and Application in Treatment of Oral Cancer Using Photothermal Energy

AbstractGraphene nanoribbons are thin sheets of graphene showing exclusive characteristics such as better drug‐loading capacity, adsorption on mammalian cells, greater surface area, and light‐absorbing ability. The current research work is to develop metformin‐adsorbed carboxyl‐functionalized oxidized graphene nanoribbons and utilize drug repurposing for the treatment of oral cancer by activating photo‐thermal radiation therapy. The nanoribbons are formulated by Hummer's method and evaluated for several characterization parameters like ATR‐ Fourier Transform Infrared (FTIR), Differential scanning calorimetry (DSC), topology, in vitro efficacy, ex vivo and in vitro cell line studies. The ATR‐FTIR spectrum of formulated nanoribbons shows distinctive peak at 3370 cm−1 (NH group) of metformin. The DSC specifies the incidence of steep endothermic crests at 235 °C (CNH3). The in vitro and ex vivo drug release studies show enhanced drug release in acidic pH (6.4) than physiological pH (7.4) with photothermal radiation. The in vitro cell line studies are processed via two‐way ANOVA that exhibits 67.74 ± 0.03% of % inhibition in presence of photothermal radiation. The study demonstrates higher inhibition of cancerous cells at lower concentration of drug and photothermal therapy in comparison to plain drug. The characteristic feature of graphene is used to develop targeted drug delivery system against the oral cancerous cells.

Brain structural abnormalities and trait impulsivity in suicidal and non-suicidal patients with bipolar disorder

BackgroundImpulsivity is a characteristic of patients with bipolar disorder (BD) and may result in a higher risk of suicide attempt (SA). Although brain structural abnormalities have been suggested in the pathophysiology of BD, the relationship to impulsivity and suicide in BD is still not clear. Methods52 euthymic patients with BD (26 of them had a history of SA) and 56 age- and sex-matched healthy controls were recruited. All participants received clinical assessment, including Barratt impulsiveness scale (BIS), and underwent structural magnetic resonance imaging examination. An automated surface-based method (FreeSurfer) was used to measure brain volume and cortical surface area. A general linear model was applied to analyze the association between brain-wise greater gray matter volume (GMV), surface area and BIS scores separately for BD patients with and without SA history. ResultsBD patients with SA history scored higher in BIS total score and subscores in attention, motor, cognitive complexity and cognitive instability than those without SA history and controls (all p < 0.01). In patients with SA history, higher BIS scores were associated with greater GMV in the left pars triangularis and greater surface area in left pars opercularis (all p < 0.01). BD patients with SA history showed a greater GMV in inferior frontal gyrus than patients without SA history (p < 0.05). LimitationThe cross-sectional design precluded examination of chronological relationships of SA, brain structural abnormalities, and trait impulsivity among BD. ConclusionsThe findings indicate that the prefrontal cortex, especially the left inferior frontal gyrus, plays a vital role in trait impulsivity and suicidal behavior among patients with BD.