Fold Enhancement Research Articles

Fabrication of g-C3N4 wrapped CAU-17 for efficient photocatalytic H2O2 production

Recently, photocatalytic production of H2O2 by semiconductors emerges as a green and potential method for green and sustainable H2O2 synthesis. In this work, a g-C3N4/CAU-17 composite with heterojunction structure was fabricated. There is a tight interface contact between g-C3N4 and CAU-17. And the g-C3N4 nanosheets was uniformly wrapped on CAU-17 surface. In the hybrid catalyst, CAU-17 provides a high surface area for g-C3N4 dispersion and the integration of g-C3N4 boosts the visible light response. Results showed that the H2O2 yield is 419.0 μmol.L-1.h-1 over g-C3N4/CAU-17 sample, which is 1.59 and 7.83 fold enhancements to bare g-C3N4 and CAU-17 counterparts. This work sheds light on the design of CAU-17-based composite photocatalysts and provides insights into H2O2 synthesis.

Droplet microreactor continuous synthesis of hierarchical Rh on CdZnS snowflakes for enhanced photocatalytic hydrogen evolution

Promising droplet microreactor-cation exchange strategy is utilized to construct the unique Rh hierarchical structure (RhHS) and Rh nanoclusters (RhNCs) on CdZnS (CZS) snowflakes. The fabricated RhHS/RhNCs/CZS achieves an optimal hydrogen evolution activity of 926.0μmol h−1 g−1, which is 5.9 and 10.5 folds enhancement that of CZS and CdS, respectively. The enhanced activity for H2 generation can be attributed to the RhHS/RhNCs (accelerating electron transfer), as well as the hierarchical structure of RhHS and CZS, which enhances reflection–absorption of visible light. Theoretical calculations reveal that Rh species can serve as new H* generation-release sites, reducing the energy barrier for hydrogen evolution. Notably, in situ Raman confirmed the Rh (Rh-H) and S (S-H) two main active sites for proton reduction during hydrogen generation. This paper provides a novel approach to constructing hierarchical structure photocatalyst (RhHS/RhNCs/CZS) for enhanced photocatalytic H2 production.

Engineering of fast-growing Vibrio natriegens for biosynthesis of poly(3-hydroxybutyrate-co-lactate)

Poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] is a highly promising valuable biodegradable material with good biocompatibility and degradability. Vibrio natriegens, owing to its fast-growth, wide substrate spectrum characteristics, was selected to produce P(3HB-co-LA). Herein, the crucial role of acetyltransferase PN96-18060 for PHB synthesis in V. natriegens was identified. Heterologous pathway of P(3HB-co-LA) was introduced into V. natriegens successfully, in addition, overexpression of the dldh gene led to 1.84 fold enhancement of the lactate content in P(3HB-co-LA). Finally, the production of P(3HB-co-LA) was characterized under different carbon sources. The lactate fraction in P(3HB-co-LA) was increased to 28.3 mol% by the modification, about 1.84 times of that of the control. This is the first successful case of producing the P(3HB-co-LA) in V. natriegens. Collectively, this study showed that V. natriegens is an attractive host organism for producing P(3HB-co-LA) and has great potential to produce other co-polymers.

Urea/thiourea based dipodal nanoreceptors: Aqueous medium fluorescent chemosensor for Zn(II) and Hg(II) ions by photoinduced electron transfer

Zinc (II) plays a pivotal role in sustaining life processes, whereas Mercury (II) stands out as a significant environmental contaminant. It is imperative to accurately identify these elements to gauge potential imbalances, whether in deficiency or excess, within biological and ecological systems. In this manuscript, four dipodal ligands JM-1 i.e. 1,1′-(2,2′-disulfanediylbis(ethane-2,1-diyl))bis(3-(4-nitrophenyl)urea), JM-2 i.e. 1,1′-(2,2′-disulfanediylbis (ethane-2,1-diyl))bis(3-(4-nitrophenyl)thiourea), JM-3 i.e. 1,1′-(2,2′-disulfanediylbis(ethane-2,1-diyl))bis(3-(naphthalen-1-yl)urea) and JM-4 i.e. 1,1′-(2,2′-disulfanediylbis(ethane-2,1-diyl))bis(3-(naphthalen-1-yl)thiourea) are synthesized and characterized by various spectroscopic methods. In order to minimize the organic solvent, organic nanoparticles (ONPs) (0.01 mM) of these ligands (2 mM) have been fabricated by reprecipitation method. ONPs of JM-1 has shown chemosensing towards Zn(II) with limit of detection upto nanomolar level i.e. 55.7 nM and ONPs of JM-4 had shown chemosensing towards Hg(II) with limit of detection as 1.35 µM while ONPs of JM-3 and JM-2 did not show any kind of chemosensing behavior towards any cation or anion. Both of ONPs of JM-1and ONPs of JM-4 showed recognition behavior via photoinduced electron transfer (PET)-off phenomenon. ONPs of JM-1 showed 18 fold enhancement in its fluorescence emission intensity when bound to Zn(II) with excellent linearity which was quite stable with respect to time.

Engineering single-atom rhodium-C3N sites on covalent organic frameworks for boosting photocatalytic hydrogen evolution

Developing efficient and stable photocatalysts for solar hydrogen (H2) energy conversion is meaningful but challenging. Herein, a novel photocatalyst with Rh single atoms (Rh SAs) anchoring in β-ketoimine-linked covalent organic frameworks (TpPa-1) via RhC3N sites is proposed for achieving highly efficient H2 production in phosphate buffer saline (PBS) solution with sodium ascorbate (SA) as sacrificial agent under visible light. TpPa-1 with abundant N and C-chelate sites provides a reliable basis for anchoring Rh single atoms. The optimized Rh SAs/TpPa-1 exhibits an outstanding hydrogen evolution activity (1836.81μmol h−1 g−1), 9.34 and 2.27 folds enhancement than that of pristine TpPa-1 and Rh NPs/TpPa-1. X-ray absorption fine structure (XAFS) combined with density functional theory (DFT) calculations reveal that the significant improvement in H2 evolution performance on Rh SAs/TpPa-1 originates from the unique RhC3N coordination environment, promoting the charge separation and migration at the atomic interface, and thus decreasing the energy barrier for H* formation. Notably, in situ Raman technique confirmed Rh SAs was the main active sites (RhH) for proton reduction.

Tumor-specific enhanced NIR-II photoacoustic imaging via photothermal and low-pH coactivated AuNR@PNIPAM-VAA nanogel

BackgroundProperly designed second near-infrared (NIR-II) nanoplatform that is responsive tumor microenvironment can intelligently distinguish between normal and cancerous tissues to achieve better targeting efficiency. Conventional photoacoustic nanoprobes are always “on”, and tumor microenvironment-responsive nanoprobe can minimize the influence of endogenous chromophore background signals. Therefore, the development of nanoprobe that can respond to internal tumor microenvironment and external stimulus shows great application potential for the photoacoustic diagnosis of tumor.ResultsIn this work, a low-pH-triggered thermal-responsive volume phase transition nanogel gold nanorod@poly(n-isopropylacrylamide)-vinyl acetic acid (AuNR@PNIPAM-VAA) was constructed for photoacoustic detection of tumor. Via an external near-infrared photothermal switch, the absorption of AuNR@PNIPAM-VAA nanogel in the tumor microenvironment can be dynamically regulated, so that AuNR@PNIPAM-VAA nanogel produces switchable photoacoustic signals in the NIR-II window for tumor-specific enhanced photoacoustic imaging. In vitro results show that at pH 5.8, the absorption and photoacoustic signal amplitude of AuNR@PNIPAM-VAA nanogel in NIR-II increases up obviously after photothermal modulating, while they remain slightly change at pH 7.4. Quantitative calculation presents that photoacoustic signal amplitude of AuNR@PNIPAM-VAA nanogel at 1064 nm has ~ 1.6 folds enhancement as temperature increases from 37.5 °C to 45 °C in simulative tumor microenvironment. In vivo results show that the prepared AuNR@PNIPAM-VAA nanogel can achieve enhanced NIR-II photoacoustic imaging for selective tumor detection through dynamically responding to thermal field, which can be precisely controlled by external light.ConclusionsThis work will offer a viable strategy for the tumor-specific photoacoustic imaging using NIR light to regulate the thermal field and target the low pH tumor microenvironment, which is expected to realize accurate and dynamic monitoring of tumor diagnosis and treatment.

Luminescent carbon dots encapsulating in Eu3+ doped gahnite spinel nanocomposite for boosting thermal sensing, advanced level III detection and intelligent anti-counterfeiting applications

The exceptional optical properties of carbon dots (CDs) position them as a highly promising category of multifunctional carbon-based nanomaterials. When hydrothermally prepared CDs are incorporated into europium-doped zinc aluminate ZnAl2O4 nanophosphors (ZAO:Eu3+ NPs) synthesized via ultrasonication method, the resulting CDs@ZAO:Eu3+ nanocomposite (NCs) exhibits a broad excitation band, with a prominent peak at approximately 393 nm, perfectly matching the emission wavelength range (500–750 nm) of near-ultraviolet (n-UV) LED chips. Significantly, the CDs (5 wt %)@ZAO:Eu3+ NCs exhibit a remarkable 12.5 folds enhancement in photoluminescence (PL) intensity compared to ZAO:Eu3+ alone, thanks to the Förster Resonance Energy Transfer (FRET) between CDs and Eu3+ ions. This enhancement in luminescence could stem from the CDs capturing electrons and facilitating energy transfer to the luminescent Eu3+ ions. Utilizing CDs to enhance fluorescence presents a straightforward and eco-friendly approach for boosting luminescence properties. Impressively, even under elevated temperatures reaching 420 K, the thermal stability of CDs (5 wt %)@ZAO:Eu3+ NCs remains outstanding, retaining 90 % of its initial luminescence intensity. This highlights its exceptional thermal stability, characterized by a high activation energy of 0.27 eV. With an impressive internal quantum efficiency (IQE) of 87.01 %, the optimized composite also achieves remarkable colour purity (CP), reaching 99.5 %. The relative sensitivity was 1.36 %, at 300 K. Thus, CDs@ZAO:Eu3+ is a promising material for non-contact optical thermometry applications. Utilizing the optimized NCs through a simple powder dusting technique effectively develops latent fingerprints (LFPs) on various surfaces, revealing fingerprints (FPs) under 365 nm UV light. Additionally, the study investigates diverse pore parameters including number, position, size, shape, and inter-spacing. Furthermore, optimized NCs are utilized to create a transparent anti-counterfeiting (AC) ink, offering effective AC features through its red emission under 365 nm UV light.

High-dose pulsed hyaluronidase for managing nasal skin necrosis following hyaluronic acid treatment in nasolabial folds: A case report

The growing popularity of soft tissue filler injections has brought attention to the associated risks, particularly vascular complications, and their treatments. This case report focuses on a 34-year-old female who developed nasal skin necrosis following hyaluronic acid (HA) filler injection for nasolabial fold (NLF) enhancement. Despite the careful procedure, complications emerged rapidly, emphasizing the critical importance of prompt diagnosis and intervention. A total of 10,000 turbidity reducing units (TRU) of hyaluronidase (HSE) were administered in a high-dose pulsed manner, alongside hyperbaric oxygen therapy. The patient experienced a gradual but significant improvement over 60 days. This case underscores the need for constant vigilance in aesthetic medicine and the potential consequences of even minute HA amounts, exceeding zero, in causing severe vascular events.

Amorphous/Crystalline Phases Mixed Nanosheets Array Rich in Oxygen Vacancies Boost Oxygen Evolution Reaction of Spinel Oxides in Alkaline Media.

As promising oxygen evolution reaction (OER) catalysts, spinel-type oxides face the bottleneck of weak adsorption for oxygen-containing intermediates, so it is challenging to make a further breakthrough in remarkably lowering the OER overpotential. In this study, a novel strategy is proposed to substantially enhance the OER activity of spinel oxides based on amorphous/crystalline phases mixed spinel FeNi2O4 nanosheets array, enriched with oxygen vacancies, in situ grown on a nickel foam (NF). This unique architecture is achieved through a one-step millisecond laser direct writing method. The presence of amorphous phases with abundant oxygen vacancies significantly enhances the adsorption of oxygen-containing intermediates and changes the rate-determining step from OH*→O* to O*→OOH*, which greatly reduces the thermodynamic energy barrier. Moreover, the crystalline phase interweaving with amorphous domains serves as a conductive shortcut to facilitate rapid electron transfer from active sites in the amorphous domain to NF, guaranteeing fast OER kinetics. Such an anodic electrode exhibits a nearly ten fold enhancement in OER intrinsic activity compared to the pristine counterpart. Remarkably, it demonstrates record-low overpotentials of 246 and 315 mV at 50 and 500 mA cm-2 in 1 m KOH with superior long-term stability, outperforming other NiFe-based spinel oxides catalysts.

Shewanella oneidensis-based artificial conductive micro-niche for hydrogen augmentation

The synergetic integration of living microorganisms and nonliving matrices into a new artificial micro-ecological system is a crucial challenge in bio-manufacturing especially towards the development of sustainable energy technology. Here we develop a way of creating a Shewanella oneidensis based conductive micro-niche to boost hydrogen production by integrating graphene, polydopamine and alginate. We reveal that both the respiratory metabolism induces localized hypoxic conditions inside the micro-niche and the wired-up extracellular electron reverses transfer pathway from the outer environment to the periplasmic hydrogenases, contributing to the enhanced hydrogen production rate which is about 12.7 folds enhancement compared with that of the free Shewanella oneidensis in solution. Significantly, the whole assembly process shows good biocompatibility, ensuring that the Shewanella oneidensis inside the micro-niche could maintain hydrogen production for 30 days. Overall, it is anticipated the hybrid integration of microorganisms and abiotic material will provide an effective strategy to modulate green biomanufacturer as well as enhance biological hydrogen production.

Abstract 6644: aPD1 treatment of urothelial cancers is synergistically enhanced by activating anti tumor immunity using vascular targeted photodynamic therapy

Abstract Background: Recurrence and progression rate following surgical treatment of locally advanced urothelial cancer is high, underscoring the unmet need to develop an effective, well tolerated treatment strategies, particularly for high grade upper tract urothelial cancer (HG-UTUC). The treatment success of low grade UTUC by vascular targeted photodynamic therapy (VTP) with WST11 (Padeliporfin) in phase I clinical trials led the FDA to approve Phase 3 trial in a fast track, orphan drug designation for low grade UTUC (ENLIGHT). Recently, treatment with immune checkpoint inhibitor (ICIs) of the PD1/PD-L1 axis has been approved for treatment of HG-UTUC. Yet, the failure rate of aPD1 therapy in HG-UTUC is high.We hypothesized that immune checkpoint inhibition needs to be complemented by the massive priming and accrual of newly activated anti-tumor immune cells through tumor immunogenic cell death. Early evidence indicated that WST11 VTP promotes anti-tumor immunity suggesting that VTP/aPD1 combinations may significantly improve the treatment success of HG-UTUC. Methods: Mice bearing s.c. MB49-Luc, were subjected to WST11 VTP at 14d post implantation at suboptimal dose of drug or partial area of illumination. 4 or 5 doses of aPD1 were intraperitonealy administrated every 3 days starting at 1d post VTP (aPD1+1), or every 3 days till 10 days post-treatment starting at 2 days before VTP (aPD1-2). Tumor progression was followed up to 90 days post treatment using IVIS. Hematoxylin-eosin staining, and multiplex immunohistochemistry (mIHC) were performed on controls and treated animals. Results: WST11 VTP with suboptimal drug dose, aPD1+1, and aPD1-2 resulted in 17%, 23% and 43% cure at day 90 post VTP. VTP at suboptimal drug dose combined with aPD1+1 or aPD1-2, resulted in 50% and 77% cure rate at 90 days, respectively. VTP with optimal drug dose (5mg/kg) but partial illumination resulted in 20% cure rate while combining this treatment modality with aPD1-2 resulted in 90% animal cure rate at day 90.At 24h post VTP mIHC showed a 2-3 fold increase of cytotoxic T cells, dendritic and NK cells, and a ~4 folds overexpression of PD1 and PD-L1 in the treated tumor tissue. At 2 days post aPD1-2 initiation, PD1 and PD-L1 apparent expression dropped to 0 and 2 folds higher than control, respectively. Following the combined VTP and aPD1-2 treatment, both PD1 and PDL-1 contents dropped down to zero and the CD8 content reached 3 folds enhancement compared to control. Conclusions: These observations indicate that elevating the content of anti-tumor immune cells in the tumor microenvironment by VTP in combination with ICI synergistically enhances the therapeutic effect providing a much higher complete cure compared with the individual therapies. The cure rate extent strongly depends on the synchronization of the two modalities providing guidelines for the clinical management of HG-UTUC treatment. Citation Format: Lilach Agemy, Keren Sasson, Tamar Yechezkel, Rachel Hamri, Raz Robas, David Kain, Avigdor Scherz. aPD1 treatment of urothelial cancers is synergistically enhanced by activating anti tumor immunity using vascular targeted photodynamic therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6644.

Comprehensive optical and thermal investigation of optimal near-infrared absorption enhancement of nano-patterned aluminum

Compelling electromagnetic (EM) properties, such as tight EM-confinement and fabrication-compatible architectures, propel the importance of metal-based nanophotonics in small-footprint devices, such as highly efficient optical absorbers. Here, we focus on boosting the absorption of optically thick bulk Aluminum (Al), the most abundant metal, solely by corrugating its surface periodically. Application-oriented, we utilize the simplest one-dimensional (1D) rectangular-grating pattern that can be remotely engraved on a large scale, e.g., using femtosecond pulsed lasers. We devise four designs for various utilizations optimized for perfect absorption around the application-abundant 1.06μm wavelength under transverse electric (TE), transverse magnetic (TM), and unpolarized (denoted TEM) irradiations. Lacking attractive plasmonic confinement properties, the s-polarization is considered electromagnetically “degenerate” to the p-polarization case, making it rarely explored in the literature of 1D-grating architectures. Nevertheless, we reveal that perfect s-polarized absorption is also attainable in such designs without adding extra layers. The designs’ performance, properties, limitations, and the propelling electromagnetic physics are theoretically and numerically discussed in-depth. A large-area sample of the TEM-optimized design was fabricated, facilitating uniquely extensive optical and radiative heating experimental investigation with realistic near-to-normal Gaussian-beam incidence. The absorption enhancement derived from wideband and single-frequency optical and radiative heating measurements agree well, also with the numerical simulations. Despite fabrication-derived thickness deviation, the design experimentally showed a 9.6-(TE), 6-(TM), and 7.8-(TEM) fold absorption enhancement over bulk Al. Considering the one-dimensional-patterning simplicity and its large-area fabrication compatibility, it is noteworthy and pioneering, particularly for the challenging s-polarization case. We also study a polarization-sensitive diffused reflection scattering pattern, evidently postulated to result from resonated surface roughness, highlighting the importance of radiative heating measurements. The elaborated original findings and methods are highly applicable alongside the prevalent material and spectrum.

Polystyrene Waste-ZnO nanocomposite film for energy harvesting via hydrophobic triboelectric nanogenerator: Transforming waste into energy

This research aimed to generate electricity from polystyrene waste materials combined with zinc oxide (ZnO) nanomaterials. Developing alternative polystyrene waste materials for generating electricity in triboelectric nanogenerator (TENG) could be beneficial in a circular economy and sustainable development. With the motivation to reduce environmental pollution by using polystyrene waste, a recycled polystyrene-ZnO nanocomposite film (rPS-ZnO NF) was synthesized and served as a triboelectric material for energy harvesting applications. ZnO nanopowder was produced by a low-temperature solution immersion method in conjunction with a simple film-casting method to prepare the rPS-ZnO NF. The effects of varying amounts of toluene as a solvent medium and the immersion time in stearic acid (SA) solution treatment on the structural properties, wettability behavior, surface morphology, chemical bonding properties, surface characteristics, and TENG performance were investigated. In this work, rPS film, rPS-ZnO NF, and SA-treated rPS-ZnO NF were paired with Kapton film as the opposite triboelectric material in constructing the vertical contact-separation mode TENG. Compared to rPS TENG, the rPS-ZnO TENG exhibited a two-fold enhancement in performance (8.2 V) in output voltage and ∼4.5 fold enhancement (28.1 μW/cm2) in power density. Furthermore, following SA treatment, the triboelectric performance further improved, reaching the highest open circuit voltage of ∼8.8 V and the highest power density of 32.0 μW/cm2 for repeated 2 N-solenoid tapping force. The hydrophobic behavior was also improved with the highest water contact angle of 134.7 (when the SA treatment immersion time was 1 h). These findings demonstrate that SA-treated rPS-ZnO NF could be a promising candidate for efficient mechanical energy harvesting with high electrical output and excellent surface wettability. This research not only exhibits an excellent output performance of SA-treated rPS-ZnO TENG, but it also sheds new light on the sustainable approach of converting polystyrene waste into energy-harvesting material.

Experimental and computational characterization of p-Sulfocalix[4]arene mediated delivery system for morin hydrate

Calix[n]arene is a class of macrocyclic compounds and has been investigated to improve the physicochemical properties of water insoluble molecules. In this work, a complex of morin hydrate (MH) drug was prepared using p-sulfocalix[4]arene (SC[4]A) as complexing agent to increase its water solubility, dissolution rate and stability. Solvent evaporation methanol was used to prepare the inclusion complex (MH-SC[4]A) between pure MH and SC[4]A and analysed by FTIR, NMR, UV, DLS, TEM, and DSC techniques. Concentration-dependent solubility study showed 22 folds enhancement of MH at 8 mM concentration of SC[4]A. The in vitro anticancer efficacy of MH against A549 cells was increased after complex formation. AO/EtBr staining study showed the more apoptosis mediated anticancer activity than native MH. Molecular geometry, stabilizing interactions, release behaviour and full-unwinding pathway of the complex were characterized by the computed Potential of Mean Force (PMF) using extended umbrella sampling. The combined computational and experimental data confirmed that our designed MH-SC[4]A complex could be utilized as a promising drug delivery carrier for hydrophobic MH.

Rapid and low temperature micro inverted pyramid texturing of silicon via copper catalyzed chemical etching for high efficiency PEDOT:PSS/silicon hybrid solar cells

Here, a rapid, low-temperature yet effective micro-inverted structuring of silicon (Si) via a low thermal budget copper catalyzed chemical etching (CuCCE) has been demonstrated for efficient hybrid heterojunction solar cells (HSCs) based on poly (3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS)/Si in the basic device design ‘Ag/PEDOT:PSS/n-Si/In:Ga’. The inverted pyramidal (IP) arrays have been obtained on a large area of the partially polished (PP) Si surface by the CuCCE in etch bath consisting of Cu(NO3)2/HF/ H2O2 in 100 mM:4.5 M:1.5 M at room temperature (30 °C). The IP-Si shows significantly reduced total surface reflectance (<7 %) than the PP-Si (>30 %) for broad spectral range. The high efficiency device on the interconnected IP-Si surface shows power conversion efficiency (PCE) >10.75 % which is direct enhancement of ∼4 folds (absolute) when compared with the HSCs made on the PP-Si surface. Such high efficiency HSCs employing the CuCCE based inverted structured solar grade Si surface and detailed analyses of PEDOT:PSS/Si interface have rarely been addressed. The junction property has been studied with the help of Nyquist plots and Mott-Schottky (C-V) analyses of impedance sepctroscopy. A direct 2.9 fold enhancement in the recombination resistance along with high barrier potential found for the optimized IP-Si structured HSCs facilitated the improved junction and minimum recombination at the PEDOT:PSS/n-Si interface. The enhanced PCE is primarily attributed to improved light harvesting ability of the IP-Si surface, junction and passivation properties with conformal coverage of the PEDOT:PSS layer. The study will help to explore the high potential of the CuCCE based IP-Si surfaces for future high efficiency devices.

Tuning optical properties of graphene quantum dots using photoexcited TiO2 for catalytic application

In this work, a simple strategy to tune the emission property of graphene quantum dots (GQDs) from green to blue color using a photochemical method is proposed. Further, the resultant materials are demonstrated to be an efficient and effective catalyst for the reduction of p-nitrophenol to p-aminophenol. Initially, green color emitting GQDs (g-GQDs) is prepared by using a chemical method involving acid reflux of graphene oxide obtained from a modified Hummer's method. Later these g-GQDs are exposed to photochemical excitation with titanium dioxide (TiO2) using UV light at a fixed wavelength of 365 nm and the resultant GQDs are observed to emit blue color (b-GQDs). Basically, the introduction of photochemically excited TiO2 nanoparticles provides excess electrons for g-GQDs to undergo further reduction to form b-GQDs leading to the formation of more sp2 hybridized domains within the carbon network than sp3 in the resultant b-GQDs. Consequently, the emission of GQDs is shifted from green to blue, and significantly ∼4 fold enhancement in the average quantum yield of GQDs is noted. These interesting research findings are analyzed by using zeta potential measurements, spectroscopic (FTIR, UV–visible, and Fluorescence) studies and microscopic investigation. Finally, TiO2 reduced GQDs are subsequently used for the reduction of p-nitrophenol to p-aminophenol, and the results obtained revealed that this material could potentially be employed as an effective catalyst.

Interfacial MoO2 nanograins assembled over graphitic carbon nanofibers boosting efficient electrocatalytic reduction of nitrate to ammonia

Electrocatalytic nitrate reduction reaction (NO3-RR) for sustainable carbon-free hydrogen carrier (NH3) production from polluted NO3- sources of industrial wastewater is very promising. Mo-based catalysts are defined as popular electrocatalytic materials, but the rational performance achievement of Mo-based catalysts in the NO3-RR remains limited. In this study, to overcome the NO3-RR activity limitation, the interfacial MoO2 nanograins assembled on the N-functional carbon nanofibers (defined as MoO2/C) were constructed by electrospun and controlled graphitizing process. The comparative catalysts dominated by molybdenum oxides namely MoO2/MoO3 were synthesized by controlled calcination in air atmosphere. The MoO2 nanograins anchored in situ on carbon nanofibres could afford more interfacial active regions and accelerate the electron transfer efficiency of the electrocatalytic process by graphitic carbon fiber network. More importantly, MoO2/C was endowed with more oxygen vacancy sites which can trap the free NO3- ions over the reactive sites to enhance the surface interaction of NO3- with catalytic sites during the reaction process. The experimental results showed that the electrocatalytic nitrate reduction performance of the catalyst MoO2/C obviously outperformed that of MoO2/MoO3 in the light of the atomic activity efficiency with a near 7.5 folds enhancement. The MoO2/C affords the highest NH3 yield of 4838.5 µg h−1 mgcat−1 and Faraday efficiency of 30 % at –0.9 V vs.RHE and was endowed with 50 h of continuous reaction stability, proving the potential in practical electrochemical water treatment involving nitrate contamination.

Lipoic acid-mediated oral drug delivery system utilizing changes on cell surface thiol expression for the treatment of diabetes and inflammatory diseases.

Lipoic acid (LA), which has good safety and oral absorption, is obtained from various plant-based food sources and needs to be supplemented through human diet. Moreover, substances with a disulfide structure can enter cells through dynamic covalent disulfide exchange with thiol groups on the cell membrane surface. Based on these factors, we constructed LA-modified nanoparticles (LA NPs). Our results showed that LA NPs can be internalized into intestinal epithelial cells through surface thiols, followed by intracellular transcytosis via the endoplasmic reticulum-Golgi pathway. Further mechanistic studies indicated that disulfide bonds within the structure of LA play a critical role in this transport process. In a type I diabetes rat model, the oral administration of insulin-loaded LA NPs exhibited a more potent hypoglycemic effect, with a pharmacokinetic bioavailability of 5.42 ± 0.53%, representing a 1.6 fold enhancement compared to unmodified PEG NPs. Furthermore, a significant upregulation of surface thiols in inflammatory macrophages was reported. Thus, we turned our direction to investigate the uptake behavior of inflammatory macrophages with increased surface thiols towards LA NPs. Inflammatory macrophages showed a 2.6 fold increased uptake of LA NPs compared to non-inflammatory macrophages. Surprisingly, we also discovered that the antioxidant resveratrol facilitates the uptake of LA NPs in a concentration-dependent manner. This is mainly attributed to an increase in glutathione, which is involved in thiol uptake. Consequently, we employed LA NPs loaded with resveratrol for the treatment of colitis and observed a significant alleviation of colitis symptoms. These results suggest that leveraging the variations of thiol expression levels on cell surfaces under both healthy and diseased states through an oral drug delivery system mediated by the small-molecule nutrient LA can be employed for the treatment of diabetes and certain inflammatory diseases.

Potential of Nitrofurantoin Cyclodextrin Nanosponge Complex to Enhance Solubility and Masking Bitter Taste

This study aimed to produce b-cyclodextrin (β-CD) based nanosponges (NS) loaded with nitrofurantoin (NFN) to improve oral bioavailability, solubility, and dissolution rate while concealing bitter tastes. The cross-linker diphenyl carbonate and β-CD were reacted in various ratios (1:1, 1:2, 1:4, 1:6, and 1:8) to produce NFN-loaded NS. The developed NS were evaluated for phase solubility study, particle size, drug loading, polydispersity index, scanning electron microscope (SEM), zeta potential, fourier transform infrared (FTIR), differential scanning calorimetry (DSC), a study of phosphate buffer at pH 7.2 for in-vitro release and taste masking ability in human volunteers. Pure NFN showed nearly 100 mcg/mL solubility in ditilled water while at 1:8 (β-CD: DPC) ratio the solubility was found to be 250 mcg/mL, i.e., nearly 2.5 fold enhancement in solubility was observed. The SEM of the NFN-loaded NS (1:8 β-CD: DPC ratio) showed highly spherical surface morphology. For formulation containing a 1:8 proportion of β-CD to DPC, the average particle size was measured at 324.78 ± 10.45 nm, possessing a low polydispersity index of 0.196 ± 0.054. It was found that the zeta potential’s value was -20.59 ± 0.4 mV, indicating sufficient electrostatic repulsion to maintain particle dispersion. FTIR, DSC study reveled excellent drug and excipient compatability. As compared to pure NFN, NFN-loaded NS showed faster release in pH 7.2 phosphate buffer. Research conducted in-vitro showed a gradual release of NFN from pure NFN throughout a two-hour period. The plain NFN suspension was found to have a pronounced bitterness. With 3.95 ± 0.57 as the average score, while the NFN nanosponges (1:8 ratio) had a mean bitterness score of only 0.10 ± 0.00. These findings suggest that the NFN (1:8 ratio) has the capacity to thoroughly cover up the bitter taste of NF.

Characterization of biosurfactant produced through co-utilization of substrates by the novel strain Pseudomonas aeruginosa NG4

Biosurfactants are extremely valuable and promising compounds that have a wide range of applications across various industries and aspects of human life. Thus, there is a great need to enhance their production yield, by developing new and more efficient fermentation methods. In pursuit of this objective, batch fermentation was carried out with different feed concentrations and addition. The results were compared in relation to their effectiveness in producing biosurfactants using Pseudomonas aeruginosa. Batch fermentation experiments were conducted using two different substrates feeding strategies, such as single substrate utilization and co-utilization of substrates. The comparison of these substrates utilization processes revealed that the co-utilization of glucose and crude glycerol was a superior cultivation strategy compared to the single substrate utilization for biosurfactant production. The biosurfactant production by P. aeruginosa from co-utilization of glucose and crude glycerol reached to a yield of 2.5 gL-1. There was about 2.2 fold enhancement in the yield compared to single carbon substrates. Such co-utilization of substrates is not reported for biosurfactant production. The biosurfactant was characterized and the presence of mono-rhamnolipid and di-rhamnolipid compounds was confirmed through FT-IR and LC-MS.