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Excitotoxicity, a neuronal death process in neurological disorders such as stroke, is initiated by the overstimulation of ionotropic glutamate receptors. Although dysregulation of proteolytic signaling networks is critical for excitotoxicity, the identity of affected proteins and mechanisms by which they induce neuronal cell death remain unclear. To address this, we used quantitative N-terminomics to identify proteins modified by proteolysis in neurons undergoing excitotoxic cell death. We found that most proteolytically processed proteins in excitotoxic neurons are likely substrates of calpains, including key synaptic regulatory proteins such as CRMP2, doublecortin-like kinase I, Src tyrosine kinase and calmodulin-dependent protein kinase IIβ (CaMKIIβ). Critically, calpain-catalyzed proteolytic processing of these proteins generates stable truncated fragments with altered activities that potentially contribute to neuronal death by perturbing synaptic organization and function. Blocking calpain-mediated proteolysis of one of these proteins, Src, protected against neuronal loss in a rat model of neurotoxicity. Extrapolation of our N-terminomic results led to the discovery that CaMKIIα, an isoform of CaMKIIβ, undergoes differential processing in mouse brains under physiological conditions and during ischemic stroke. In summary, by identifying the neuronal proteins undergoing proteolysis during excitotoxicity, our findings offer new insights into excitotoxic neuronal death mechanisms and reveal potential neuroprotective targets for neurological disorders.

This work describes the utilization of D-A-D type organic semiconductor, 4,4’-(benzo[c] [1,2,5]selenadiazole-4,7-diyl)bis(N,N-diphenylaniline), denoted as Se-2TPA, containing benzoselenadiazole (BSe) as acceptor core and end-capped with triphenylamine (TPA) donor units as donor materials in solar cells. Superlatively, the attachment of TPA donor moiety in BSe acceptor unit enlarged the conjugated system by extending the π-bonding which effectively tuned the optical and electrochemical properties of Se-2TPA. The bulk heterojunction organic solar cell (BHJ-OSCs) with configuration of ITO/cp-TiO2/Se-2TPA:PC61BM/Au showed power conversion efficiency (PCE) of ∼4.12% with short circuit current (Jsc) value of ∼11.28 mA/cm2, open circuit voltage (Voc) of ∼0.775 V and fill factor (FF) of ∼0.48. PCE significantly increased from ∼4.12% to ∼5.29% when 1,8-diiodooctane (DIO) was added as an additive in Se-2TPA:PC61BM blend which associated with less phase separation and improved the charge extraction. The fabricated BHJ-OSCs processed with 3% DIO, ITO/cp-TiO2/Se-2TPA:PC61BM/Au configuration displayed a long-term stability under air condition at an ambient temperature by maintaining ∼80% PCE for the duration of 30 days. The advantages of easy synthesis, low cost and promising cell performance supported Se-2TPA as successful organic semiconductor for BHJ-OSCs.

Etoposide is widely used in the management of different solid tumors as well as leukemias but low aqueous solubility and poor intestinal permeability limit its oral efficacy. The present investigation aimed to enhance the oral bioavailability of etoposide through formation of nanoemulsion employing Box-Behnken design for formulation optimization. The effect of nanoemulsion composition (concentration of labrasol and solutol HS 15) and process parameters (sonication time) on globule size and polydispersity index were investigated. The optimized formulation was found to be with globule size in-vivo bioavailability profile of developed formulation, marketed product, and API suspension was also investigated after oral administration in Wistar rats. The relative bioavailability of etoposide loaded nanoemulsion system was 2.5 times higher than the drug suspension and 1.7 times higher than the marketed capsule (Posid®). The findings of the current investigation proved that the developed nanoemulsion system is helpful to improve the bioavailability of P-gp substrate drugs like etoposide that have low oral absorption.

The study presents a novel route towards the synthesis of NiO nanostructures by using various green amino acids. The nanostructures were obtained by hydrothermal methodology assisted by threonine, arginine, aspartic acid, leucine, isoleucine and serine respectively. The characterization of the synthesized materials was studied by different techniques such as XRD, SEM and TEM. The synthesized structural features were explored for their electro-chemical properties and used for fabrication of glucose sensors based on non-enzymatic functions. The developed sensors demonstrated a promising result in terms of sensitivity, selectivity, and stability. The most important finding in the present study is the oxidation of glucose at low potentials such as 0.125, 0.23, 0.093, 0.26, 0.037, and -0.02 V respectively for the isoleucine, leucine, serine, threonine, arginine, and aspartic acid assisted NiO nanostructures. This unique finding is attributed to the morphology of different nanostructures of NiO grown with the addition of green additives. The glucose sensing ability of glucose was not affected in presence of species such as uric acid, ascorbic acid, and other carbohydrates due to their close oxidation potential compared with glucose. The sensitivities of proposed non-enzymatic glucose sensors were found to be for the isoleucine, leucine, serine, threonine, arginine, and aspartic acid assisted NiO nanostructures as 4930, 3173, 2648, 1724, 1070, and 525 µA/mM/cm2 respectively. The maximum sensing capability was recorded for isoleucine structures which showed higher sensitivity of 4930 µA/mM/cm2, greater stability and excellent anti-interference capability compared to other nanostructures. The limit LOD and LOQ were also found and remain 0.01 (S/N = 3) and 1.9 µM individually, for the newly developed method for the sensor based on NiO grown with isoleucine amino acid. The potential application of isoleucine assisted NiO nanostructures composite material for the blood sample quantities analysis which further it demonstrates the feasibility of developed based for the non-enzymatic glucose sensor.

Quantum dot solar cells have received significant attention in comparison to standard solar cells because of their hybrid nature, low production costs, and higher power conversion efficiency. Although quantum dot solar cells (QDSCs) have several benefits over ordinary solar cells, their performance lags due to carrier combination within the quasi-neutral region (QNR). The electron transport layer (ETL) and hole transport layer (HTL) are the two layers that have the most effect on QDSC performance. This numerical analysis is carried out by using the Solar Cell Capacitance Simulator-1 dimensional software (SCAPS-1D). In this paper, the optimization of two different device structure investigations is performed. In this proposed device structure, WS2 and IGZO are used as two ETL, CdS is used as a buffer layer, Sb2Se3 is used as an absorber layer, and PbS as HTL. Initially, the optimization of the device has been performed, followed by depth analysis of the doping densities. Resistance analysis is also performed to illustrate the effect of resistance on the device. Further, the impact of temperature on the device parameters is also represented, followed by a contour plot between thickness and bandgap for both devices. The impact of the series and shunt resistance on the performance of the solar cell is investigated. The effect of temperature is studied further, and it is observed that the solar device is temperature-sensitive. Finally, the optimized performance with IGZO ETL with PCE of 20.94% is achieved.

Binary metal oxide, nickel-cobalt oxide (NiCo2O4), was hydrothermally synthesized for the successful utilization as electrochemical electrode in chemical sensor. Benefited from the large surface area, binary NiCo2O4 stacked hexagonal nanoplates (HNPs) based electrode was utilized for the electrochemical sensing application towards teratogenic chemical i.e. 3-methoxypropionitrile (3-MPN). The sensing results displayed a reproducible sensitivity of ~605 μAμM−1cm−2, detection limit of ~11.8 μM with the correlation coefficient (R) of ~0.99502 and good linearity from ~10 μM to ~100 μM. Stability and repeatability of binary NiCo2O4 stacked HNPs based electrode was investigated with satisfactory results. Our synthesized binary NiCo2O4 stacked HNPs based electrode is promising for sensor applications and thus, enlightens the possibility of synthesizing other binary oxide materials.

The use of photocatalysts for acquiring direct photon energy from sunlight is a promising way to clean the environment, particularly the remediation of contaminants from water. In this work, firstly π-conjugated organic semiconductor configuring benzoselenadiazole, 4-(3,5-bis(trifluoromethyl) phenyl)-7-(5'-hexyl-[2,2'-bithiophen]-5-yl)-benzo [c] (Kümmerer, 2009; Chen et al., 2018; Randeep et al., 201) selenadiazole, abbreviated as (RTh-Se-F), was synthesized. The designed RTh-Se-F with an extended π-conjugation showed good optical properties in the visible region and estimated a low optical band gap of ∼2.02 eV . The molecular orbitals i.e. HOMO (-5.33 eV) and LUMO (-3.31 eV) for RTh-Se-F organic semiconductor were suitably aligned to energy levels of (Madhavan et al., 2010Madhavan et al., 2010)-Phenyl-C

Excitotoxicity is a neuronal death process initiated by over-stimulation of ionotropic glutamate receptors. Although dysregulation of proteolytic signaling networks is critical for excitotoxicity, the identity of affected proteins and mechanisms by which they induce neuronal cell death remain unclear. To address this, we used quantitative N-terminomics to identify proteins modified by proteolysis in neurons undergoing excitotoxic cell death. We found that most proteolytically processed proteins in excitotoxic neurons are likely substrates of calpains, including key synaptic regulatory proteins such as CRMP2, doublecortin-like kinase I, Src tyrosine kinase and calmodulin-dependent protein kinase IIβ (CaMKIIβ). Critically, calpain-catalyzed proteolytic processing of these proteins generates stable truncated fragments with altered activities that potentially contribute to neuronal death by perturbation of synaptic organization and function. Blocking calpain-mediated proteolysis of one of these proteins, Src protected against neuronal loss in a rat model of neurotoxicity. Extrapolation of our N-terminomic results led to the discovery that CaMKIIα, an isoform of CaMKIIβ undergoes differential processing in mouse brains under physiological conditions and during ischemic stroke. In summary, our findings inform excitotoxic neuronal death mechanism and suggest potential therapeutic strategies for neuroprotection.In BriefAmeen, et al. used a proteomic method called N-terminomics to identify proteolytic events occurring in neurons during excitotoxicity. They found that most proteolytic processing is mediated by calpains, resulting in the generation of stable truncated fragments with the potential to induce synaptic dysfunction and loss, eventually leading to neuronal death. They further showed that some of these proteolytic processed proteins, such as the protein kinases Src and CaMKII, are potential targets for neuroprotection.HighlightsIdentification of over 300 neuronal proteins cleaved by calpains to form stable truncated fragments during excitotoxicity.The calpain cleavage sites of these proteins unveil for the first time the preferred cleavage sequences of calpains in neurons.These pathological proteolytic events potentially induce synaptic dysfunction and loss, which likely contribute to excitotoxic neuronal death.Some of the neuronal proteins proteolyzed by calpains are potential targets of neuroprotection.Graphical abstract: Pathological proteolytic events in neurons during excitotoxicity unveiled by N-terminomic analyses(A) N-terminomic and global proteomic analyses identified neo-N-terminal sites and neuronal proteins undergoing significant abundance changes during excitotoxicity. (B) Informatic analysis of the proteomic results predicted (i) the preferred sequences of proteolytic processing of neuronal proteins catalyzed by calpains during excitotoxicity and (ii) perturbation of synaptic organization and functions as the major consequence of calpain-mediated proteolytic events. (C) Validation of these predictions and further experimentations unveiled: (i) calpain-mediated cleavage of proteins associated with synaptic damage in excitotoxic neurons, (ii) a new mechanism of dysregulation of CaMKIIα and CaMKIIβ, which are key protein kinases governing synaptic dysfunctions and excitotoxic neuronal death and (iii) potential therapeutic targets such as the protein kinases Src and CaMKII for neuroprotectionOne Sentence SummaryProteolytic events in neurons during excitotoxicity inform neuronal death mechanism and potential therapeutic strategies for neuroprotection.

The present work documents the synthesis of a new and highly energetic indandione based D-π-A planar molecule, 2-(5″-hexyl-[2,2′:5′2″ terthiophen]-5-yl) methylene)-1H- indene-1,3(2H) dione, H3T-ID), as donor material for bulk-heterojunction organic solar cells (BJH-OSCs). The photophysical properties, optoelectrical characterization and microscopic images were thoroughly studied. H3T-ID exhibited good absorption behavior with maximum absorbance at ~495 nm and displayed the optical band gap of ~1.98 eV. The existence of π-spacer and hexyl side chain in H3T-ID significantly improved the thin film morphology, molecular packing and enhanced the charge transport. H3T-ID organic molecule acquired well-matched HOMO and bountifully higher LUMO energy levels w.r.t. PC61BM acceptor. The photovoltaic characteristics of the fabricated BHJ-OSC using H3T-ID as donor and PC61BM as acceptor displayed maximum PCE = ~4.05%, good JSC = ~10.43 mAcm−2, VOC = ~0.77 V and FF = 0.51. The stability test revealed that the fabricated BHJ-OSCs showed good reproducibility and stability by retaining over ~80% of its initial PCE for 15 days without encapsulation.

Benzoselenadiazole as the central acceptor unit with terminal donor unit of n-hexylbithiophene was chosen to design the symmetric donor-acceptor-donor (D–A–D) configuration based small organic chromophore, 4,7-bis(5′-hexyl-[2,2′-bithiophen]-5-yl)benzo[c][1,2,5]selenadiazole, RTh-BSe-ThR, for the fabrication of solution-processed bulk-heterojunction organic solar cells (BHJ-OSCs). RTh-BSe-ThR chromophore showed assuring solubility in common organic solvents and exhibited wider absorption in the visible region with an optical band gap (Egopt) of ∼1.87 eV. Benzoselenadiazole unit with two n-hexylbithiophene units exhibited an excellent electrochemical behavior with the highest occupied molecular orbital (HOMO) of −5.38 eV and the lowest unoccupied molecular orbital (LUMO) of −3.51 eV. The fabricated BHJ-OSCs with RTh-BSe-ThR:PC61BM (1:3, w/w) blend thin film displayed a power conversion efficiency (PCE) of ∼3.46% and a high value of short circuit current density (JSC) of ∼11.20 mA/cm2. The enhancement in the photovoltaic parameters might be attributed to the significant improvements in the interfacial area of bulk heterojunction which might enhance the light harvesting property and the shunt resistance of the blend thin films.

A quick and efficient approach was employed for the growth of nanocrystalline tungsten oxide (WO3) thin films using one-step hot filament chemical vapor deposition (HFCVD) method at low temperature. In a typical experiment, the parent material tungsten (W) was subjected to oxidation, gasification and its subsequent condensation to obtain the uniform deposition of WO3 thin film on silicon substrate at significantly low temperature of ∼200 °C. Prepared WO3 thin film possessed the cauliflower nanostructure (WCNs) with typical monoclinic WO3 crystal structure. Prepared WCNs thin films were applied for the detection of hydrogen (H2) gas at 100 ppm. H2 response increased with rise in temperature and the maximum response of ∼87% was obtained at the optimized temperature of ∼250 °C with response time 180 s.

In this work, the structural, optical, morphological, and sensing features of tungsten oxide (WO3) thin film deposited on a silicon substrate via hot-filament chemical vapor deposition (HFCVD) are described. The experimental characterization tools, such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet-visible (UV-Vis), and Fourier transform infra-red (FTIR) spectroscopies, etc., were used to determine the properties of WO3 NPys thin films. The grown WO3 thin film illustrated closely packed porous pyramidal nanostructures (NPys) of improved grain size properties. The diffraction analysis revealed (100) and (200) of WO3 phases, suggesting the classic monoclinic crystal WO3 structure. HFCVD grown WO3 NPys thin film was employed as electro-active electrode for detecting ethylenediamine in 10 mL of 0.1 M phosphate buffer solution (PBS) by varying the ethylenediamine concentrations from 10 μM to 200 μM at room temperature. With a detection of limit (LOD) of ~9.56 μM, and a quick reaction time (10 s), the constructed chemical sensor achieved a high sensitivity of ~161.33 μA μM−1 cm−2. The durability test displayed an excellent stability of electrochemical sensor by maintaining over 90% sensitivity after 4 weeks of operation. This work provides a strategy for a facile preparation of WO3 NPys thin film electrode for sensor applications.

This work narrates the preparation of efficient nanomaterials framework of zinc oxide (ZnO) nanoglobules (NGs) with graphene oxide (GO) and reduced graphene oxide (rGO) for the fabrication of rapid multiple ion field-effect transistor (MI-FET) sensors. Prepared ZnO-NGs@GO and ZnO-NGs@rGO nanocomposites were broadly analyzed by different analytical techniques to study their morphological, structural, compositional, and electrochemical properties. As electrode materials, ZnO-NGs@GO and ZnO-NGs@rGO were used to fabricate MI-FETs sensor for the detection of multiple ions such as Ni (II), Co (II), Cu (II), Cr (III), Fe (II), and Bi (II) ions. ZnO-NGs@GO and ZnO-NGs@rGO modified MI-FETs sensor exhibited excellent responses towards Cr (III) and Cu (II) ions, which presented the remarkable sensitivities of ~49.28 mA μM−1. cm−2 (Cr (III) ions) and ~185.32 mA μM−1. cm−2 (Cu (II) ions), respectively. The fabricated MI-FETs sensor displayed good dynamic linear detection of ions with low limit of detection (LOD) values of ~7.05 μM and ~14.9 μM for ZnO-NGs@GO and ZnO-NGs@rGO electrodes, respectively. Efficient charge transfer over electrode considerably enhanced the trace detection of Cr (III) and Cu (II) ions. The fabricated MI-FETs sensor platform exhibited extraordinary reproducibility and excellent stability of sensing performance and thus, confirmed delightful potential to sprout a useful tool for water maintaining system.

The effective detection of dichloromethane (DCM) was performed by hexagonal zinc oxide (ZnO) nanopyramids (NPys) modified disposable screen printed electrode (SPE) for the fabrication of reproducible, highly sensitive and reliable chemical sensors. ZnO NPys were synthesized by a simple hydrothermal procedure using zinc acetate as precursor and oleylamine as surfactant. Well-grown hexagonal pyramids like structures were incurred in a high aspect ratio. The optical, structural and the compositional characterizations confirmed a good quality and crystallinity possessing a wide band gap (Eg) of ∼3.29 eV of ZnO NPys. The hexagonal ZnO NPys modified disposable SPE chemical sensor showed a good sensing behavior with a sensitivity of ∼293.5 µA/µM/cm2 and limit of detection (LOD) of ∼17.3 µM toward the detection of DCM. The electrochemical sensor based on hexagonal ZnO NPys modified disposable SPE demonstrated an excellent linearity in the range of ∼100 nM to 200 µM and a good retention coefficient (R) of ∼0.982055 which resulted in good sensing properties.

This paper illustrates the synthesis of a new donor-π-donor (D-π-D) type fluorene and hexyl-bithiophene units based chromophore, named as 5′,5‴-(9,9-dioctyl-9-H-fluorene-2-7-diyl)bis (5-hexyl-2,2′-bithiophene) (9RFL) via simple Suzuki coupling reaction. The synthesized 9RFL chromophore was applied as donor for solution-processed bulk-heterojunction (BHJ)-organic solar cells (OSCs). 9RFL chromophore showed the acceptable electrochemical behavior with estimated HOMO and LUMO energy levels of −5.43 eV and −3.50 eV, respectively. A reasonable power conversion efficiency (PCE) of ∼2.13% along with high short circuit current density (JSC) of ∼9.91 mA/cm2, and open circuit voltage (VOC) of ∼0.718 V were attained by the fabricated BHJ-OSCs with the configuration of ITO/PEDOT:PSS/9RFL:PC61BM (1:3, w/w ratio)/Au.

In the present work, we prepared N-doped ZnO by a facile chemical vapor deposition method and used it for the degradation of wastewater containing noxious rose bengal (RB) dye under visible-light stimulation. The as-prepared N-doped ZnO and the undoped ZnO (used as a control sample) were characterized by numerous spectroscopic and microscopic methods. These analyzing results confirmed the successful formation of the N-doped ZnO compound and it could be implemented for wastewater treatment. Interestingly, the N-doped ZnO material confirmed the maximum RB dye degradation efficiency (96.90%) and was shown to be 154% more efficient than undoped ZnO (62.95%) within 100 min of visible-light irradiation. The bandgap energy was considerably decreased after the incorporation of N onto the ZnO matrix compared to undoped ZnO. The improved photocatalytic performance is because of the reduction of bandgap energy, which suppressed the electron–hole pair recombination. In addition, a plausible photodegradation mechanism of RB dye was discussed employing N-doped ZnO under visible light. The findings show that our as-synthesized product can be used to eliminate contaminants, which provides a new avenue for effective implications.

The nickel (Ni) and iron (Fe) co-doped zinc oxide nanoparticles, Zn0.97Fe0.01Ni0.02O NPs, were synthesized by a simple hydrothermal method and used for the fabrication of a highly sensitive, reliable and reproducible field effect transistor (FET) sensor for the detection of hexahydropyridine chemical. The highly dense spherical NPs of well-defined crystalline structure of the typical wurtzite hexagonal phase were obtained. The energy-dispersive X-ray spectroscopy (EDS) analysis confirmed the synthesis of Zn0.97Fe0.01Ni0.02O NPs. The highly accessible FET-sensor was fabricated by depositing Zn0.97Fe0.01Ni0.02O NPs on SiO2/Si substrate and the sensing performances were measured towards the detection of different concentrations of hexahydropyridine chemical. Zn0.97Fe0.01Ni0.02O NPs modified FET-sensor showed the high sensitivity of ∼62.28 μA μM−1 cm-2 and the good detection limit of ∼79 μM with correlation coefficient (R) of ∼0.96405 and a short response time (10 s) towards hexahydropyridine chemical.

This paper explains the preparation of SnO2-Sb2O3 composite catalyst by solid state reaction process, and posteriorly employs as an alternative and promising photocatalyst for Brilliant Green (BG) dye degradation under solar irradiation. SnO2 and Sb2O3 composite samples with varying proportions of SnO2 and Sb2O3 were created, with 2 to 5 w t% SnO2 added to the Sb2O3 sample. The synthesized samples were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS) and UV-visible diffuse reflectance spectroscopy (DRS). The results showed that the 3% SnO2-Sb2O3 sample presented higher catalytic activity compared to the others, besides SnO2 and Sb2O3 alone, reaching ~90% of decolonization and ~87% of COD removal at 180 min. This remarkable photocatalytic activity may be associated to its favorable band gap energy. Kinetic data fitted well with pseudo-first-order kinetic model. Therefore, the SnO2-Sb2O3 composite prepared in this work can be considered as an effective photocatalyst for elimination of colored-contaminants, such as BG dye, from wastewater.

A new and effective planar D-&pi, A configured small organic molecule (SOM) of 2-5-(3,5-dimethoxystyryl)thiophen-2-yl)methylene)-1H-indene-1,3(2H)-dione, abbreviated as DVB-T-ID, was synthesized using 1,3-indanedione acceptor and dimethoxy vinylbenzene donor units, connected through a thiophene &pi, spacer. The presence of a dimethoxy vinylbenzene unit and &pi, spacer in DVB-T-ID significantly improved the absorption behavior by displaying maximum absorbance at ~515 nm, and the reasonable band gap was estimated as ~2.06 eV. The electronic properties revealed that DVB-T-ID SOMs exhibited promising HOMO (&minus, 5.32 eV) and LUMO (&minus, 3.26 eV). The synthesized DVB-T-ID SOM was utilized as donor material for fabricating solution-processed bulk heterojunction organic solar cells (BHJ-OSCs) and showed a reasonable power conversion efficiency (PCE) of ~3.1% with DVB-T-ID:PC61BM (1:2, w/w) active layer. The outcome of this work clearly reflects that synthesized DVB-T-ID based on 1,3-indanedione units is a promising absorber (donor) material for BHJ-OSCs.

We demonstrate the hydrothermal synthesis of three dimension (3D) peony-like morphology of zinc gallate (ZnGa