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The goal of this research is to synthesize bismuth molybdate (γ-Bi2MoO6) nanoparticles via hydrothermal approach which involved the use of bismuth nitrate and ammonium molybdate as a precursor. The resultant product was undergoing spectroscopic characterization techniques to understand the properties of γ-Bi2MoO6 NPs. Additionally, the absorbance and band gap of the bismuth molybdate nanoparticles were measured using a UV–visible spectrophotometer. According to the results obtained by the band gap, the calculation is around 2.4 eV. The photocatalytic efficacy was investigated using methylene blue (MB) dye by utilizing a visible light source for 2 h. The formation of hydroxyl radicals is the responsible species for degradation confirmed by the scavenger analysis. The reusability and photostability were determined by recycling studies. According to the degradation efficiency calculation, about 93.4% MB dye was effectively degraded by the synthesized bismuth molybdate. Furthermore, the electrochemical impedance analysis revealed the capacitance of the bismuth-modified electrode. [ABSTRACT FROM AUTHOR]

Achieving environmentally friendly solvent-processed high-performance organic photovoltaic cells (OPVs) is a crucial step toward their commercialization. Currently, OPVs with competitive efficiencies rely heavily on harmful halogenated solvent additives. Herein, the green and low-cost 9-fluorenone (9-FL) is employed as a solid additive. By using the o-xylene/9-FL solvent system, the PM6:BTP-eC9-based devices deliver power-conversion efficiencies of 18.6% and 17.9% via spin-coating and blade-coating respectively, outperforming all PM6:Y-series binary devices with green solvents. It is found that the addition of 9-FL can regulate the molecular assembly of both PM6 and BTP-eC9 in film-formation (molecule-level mixing) and post-annealing (thermal-assisted molecular reorganization with additive volatilization) stages, so as to optimize the blend morphology. As a result, the charge transport ability of donor and acceptor phases are simultaneously enhanced, and the trap-assisted recombination is reduced, which contributes to the higher short-circuit current density and fill factor. Moreover, the generation of photo-induced traps is significantly suppressed, resulting in improved stability under illumination. It is further demonstrated the excellent universality of 9-FL in various photoactive systems, making it a promising strategy to advance the development of eco-friendly OPVs. [ABSTRACT FROM AUTHOR]

The perovskite/silicon tandem solar cell (TSC) has attracted tremendous attention due to its potential to breakthrough the theoretical efficiency set for single‐junction solar cells. However, the perovskite solar cell (PSC) designed as its top component cell suffers from severe photo‐induced halide segregation owing to its mixed‐halide strategy for achieving desirable wide‐bandgap (1.68 eV). Developing pure‐iodide wide‐bandgap perovskites is a promising route to fabricate photostable perovskite/silicon TSCs. Here, we report efficient and photostable pure‐iodide wide‐bandgap PSCs made from an anti‐solvent‐free (ASF) technique. The ASF process is achieved by mixing two precursor solutions, both of which are capable of depositing corresponding perovskite films without involving anti‐solvent. The mixed solution finally forms Cs0.3DMA0.2MA0.5PbI3 perovskite film with a bandgap of 1.68 eV. Furthermore, methylammonium chloride additive is applied to enhance the crystallinity and reduce the trap density of perovskite films. As a result, the pure‐iodide wide‐bandgap PSC delivers efficiency as high as 21.30 % with excellent photostability, the highest for this type of solar cells. The ASF method significantly improves the device reproducibility as compared with devices made from other anti‐solvent methods. Our findings provide a novel recipe to prepare efficient and photostable wide‐bandgap PSCs. [ABSTRACT FROM AUTHOR]

Electron shuttles are pivotal in enhancing the conversion efficiency at the biotic‐abiotic interface within microbial photoelectrochemical systems. Nevertheless, the potentially toxic effects of electron shuttles on microbial cells and their instability when exposed to light are often overlooked. This concept highlights the attention paid to electron shuttles in microbial photoelectrochemical systems, such as the cytotoxicity, the photoexcited state, and the photostability. Furthermore, it offers theoretical guidance for selecting electron shuttles to optimize sustainable energy production and environmental remediation. [ABSTRACT FROM AUTHOR]

In order to expand the application of bismuth vanadate (BiVO4) to the field of photoelectrochemistry, researchers have explored the potential of BiVO4 in catalyzing or degrading organic substances, potentially presenting a green and eco-friendly solution. A study was conducted to investigate the impact of electrolytes on the photocatalysis of benzyl alcohol by BiVO4. The research discovered that, in an acetonitrile electrolyte (pH 9) with sodium bicarbonate, BiVO4 catalyzed benzyl alcohol by introducing saturated V5+. This innovation addressed the issue of benzyl alcohol being susceptible to catalysis in an alkaline setting, as V5+ was prone to dissolution in pH 9 on BiVO4. The concern of the photocorrosion of BiVO4 was mitigated through two approaches. Firstly, the incorporation of a non-aqueous medium inhibited the formation of active material intermediates, reducing the susceptibility of the electrode surface to photocorrosion. Secondly, the presence of saturated V5+ further deterred the leaching of V5+. Concurrently, the production of carbonate radicals by bicarbonate played a vital role in catalyzing benzyl alcohol. The results show that, in this system, BiVO4 has the potential to oxidize benzyl alcohol by photocatalysis. [ABSTRACT FROM AUTHOR]

Introduction: Sennosides are the main active constituents of the dried leaves and/or pods of Senna alexandrina Mill. that are used as laxatives. A hypothesis is that aglycones are formed during the degradation of sennosides. However, it is unknown, whether this happens under visible light exposure and how photosensitive sennosides behave in solution. Objectives: Pure anthraquinone glycosides were tested on their behaviour during sample preparation in the lab under visible light exposure in dependence on the instability of the solvent. Materials and methods: Samples before and after exposure were analysed using UHPLC with UV/Vis and MS detection. Results: Under visible light protection, the solutions were stable for 14 days at room temperature whereas a loss of 20%–60% was measured after 1 day of light exposure. The loss of sennosides due to degradation can be as fast as up to 2%–2.5% per hour, which might have a tremendous impact on phytochemical analysis results during the course of an analysis. The formation of aglycones was not observed in the degradation of sennosides and rhein‐8‐O‐glucoside. Conclusion: Aglycones could not be found as a result of the forced degradation. The solutions of sennosides clearly need to be protected from light to obtain reliable analytical results, and light protection is a major point for the stability of liquid preparations. Sennosides are the main active constituents of leaves and pods of Senna alexandrina Mill., used as laxatives. Light‐induced degradation of sennoside references during analysis is yet unknown. Samples before and after exposure were analysed using UHPLC‐UV/Vis/MS. Under light protection, the solutions were stable for 14 days, whereas a loss of 20%−60% after 1 day of visible light exposure was observed. The degradation rate ranged between 2% and 2.5%/h. Formation of aglycones was not observed during degradation of sennosides and rhein‐8‐O‐glucoside. [ABSTRACT FROM AUTHOR]

Organic photovoltaics (OPVs) show great promise for both outdoor and indoor applications. However, there remains a lack of understanding around the stability of OPVs, particularly for indoor applications. In this work, the photostability of the poly[(thiophene)‐alt‐(6,7‐difluoro‐2‐(2‐hexyldecyloxy)quinoxaline)]:2,2′‐((2Z,2′Z)‐((4,4,9,9‐tetrahexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐2,7‐diyl)bis(methanylylidene))bis(3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile blend is investigated for both outdoor and indoor applications. Photostability is found to vary drastically with illumination intensity. Devices under high‐intensity white light‐emitting diode (LED) illumination, with their short‐circuit current density (JSC) matching JSC–EQE for AM1.5 G illumination, lose 42% of their initial performance after 30 days of illumination. Contrastingly, after almost 47 days of illumination devices under 1000 lux white LED illumination show no loss in performance. The poor photostability under 1 sun illumination is linked to the poor photostability of IDIC. Through Raman spectroscopy and mass spectrometry, IDIC is found to suffer from photoisomerization, which detrimentally impacts light absorption and carrier extraction. In this work, it is highlighted that under low light levels, the requirement of intrinsic material photostability may be less stringent.

[Display omitted] To significantly improve phase photostability, CsPbI 3 absorber films were modified by introducing isonipecotic acid. This has resulted in remarkable long-term operational stability of CsPbI 3 -based perovskite solar cells with optimally modified light absorbers. [ABSTRACT FROM AUTHOR]

In the past few years, there has been an increasing interest in mycosporines—UV-absorbing molecules—bringing important insights into their intrinsic properties as natural sunscreens. Herein, mycosporine-serinol and gadusol (enolate form)/gadusolate were exposed to UV radiation via a solar simulator and the photostability was assessed in pure water and different natural matrices like river, estuary and ocean water. In general, this study revealed that the photodegradation of gadusolate and mycosporine-serinol was higher in natural matrices than in pure water due to the generation of singlet oxygen on UV irradiation. In pure water, in terms of photostability, both gadusolate and mycosporine-serinol were found to offer good protection and high performance in terms of photodegradation quantum yield ((0.8 ± 0.2) × 10−4 and (1.1 ± 0.6) × 10−4, respectively). Nonetheless, the photostability of mycosporine-serinol was found to be superior to that of gadusolate in natural water, namely, ocean, estuary and river. The present work highlights how mycosporine-serinol and gadusolate resist photodegradation, and supports their role as effective and stable UV-B sunscreens.

The pulmonary vascular system plays a crucial role in maintaining normal physiological functions, and perturbations in this network often serve as indicators for various fatal diseases. Thus, accurate mapping and assessment of the intricate anatomical details of pulmonary vasculature is essential for the investigation of the underlying mechanism of these diseases. Yet it is considered a tough challenge as traditional imaging techniques offer limited representations of the vasculature network in the lung, while optical imaging methods face limitations from tissue depth. To overcome these obstacles, in this study, an AIENP‐reinforced DISCO method, for whole‐tissue 3D reconstruction of pulmonary capillaries is presented. Combining AIENPs, hydrogel‐enhanced scaffolds, and solvent‐based DISCO procedures, the method successfully visualizes the entire network of mouse pulmonary capillaries with a significantly shortened timeframe and cost. The whole process including labeling and clearing takes 6 days and it costs ≈ 5 USD to stain the lung vasculature of an adult mouse. Moreover, the study provides valuable insights for detecting pulmonary vascular abnormalities. This fast and cost‐effective technique opens new avenues for developing better fluorophores compatible with tissue optical clearing and offers insights for in‐depth research on pulmonary pathophysiology. [ABSTRACT FROM AUTHOR]

Wide‐bandgap (WBG) perovskite solar cells (PSCs) have been widely used as the top cell of tandem solar cells. However, photoinduced phase segregation and high open‐circuit voltage loss pose significant obstacles to the development of WBG PSCs. Here, a two‐step small‐size A‐site and large‐size X‐site incorporation strategy is reported to modulate the lattice distortion and improve the film quality of WBG formamidinium‐methylammonium (FAMA) perovskite films for photostable PSCs based on two‐step deposition method. First, CsI with content of 0–20% is introduced to tune the lattice distortion and film quality of FAMA perovskite with a bandgap of 1.70 eV. Then, 4% RbI is incorporated to further modulate the perovskite growth and lattice distortion, leading to the suppression of photoinduced phase segregation in the resultant RbCsFAMA quadruple cation perovskites. As a result, the 20%CsI/4%RbI‐doped device obtains a promising efficiency of 20.6%, and the corresponding perovskite film shows good photothermal stability. Even without encapsulation, the device can maintain 92% of its initial efficiency after 1000 h of continuous operation under 1 sun equivalent white light‐emitting diode illumination. [ABSTRACT FROM AUTHOR]

Capsaicin and curcumin, the active components of chili and turmeric, are prone to instability when exposed to light. Therefore, this research aimed to enhance the photostability of both extracts via the use of antioxidants, natural sunscreen, and nanostructured lipid carriers (NLCs). NLCs were chosen for this this study due to their advantages in terms of stability, drug loading capacity, occlusive effect, skin penetration, and controlled release. The photostability of each extract and extracts mixed with antioxidants, including grape seed extract, tea extract, and chlorogenic acid, were determined. Chlorogenic acid can enhance the photostability of capsaicin from 6.79 h to 16.50 h, while the photostability of curcumin increased from 9.63 h to 19.25 h. In addition, the use of natural sunscreen (sunflower oil) also increased the photostability of capsaicin and curcumin. The mixed extracts were then loaded into NLCs. The particle size of the formulation was 153.73 nm with a PDI value of 0.25. It exhibited high entrapment efficiency (more than 95%). In addition, it effectively reduced the decomposition of capsaicin and curcumin. Importantly, the natural stabilizers chosen for NLC fabrication significantly improved the photostability of curcumin and capsaicin by 600% and 567% compared to the unstabilized counterparts. This improvement contributes to the sustainability and bioavailability of these compounds in both cosmeceutical and pharmaceutical products. [ABSTRACT FROM AUTHOR]

Prolonged ultraviolet exposure results in the formation of cyclobutane pyrimidine dimers (CPDs) in RNA. Consequently, prebiotic photolesion repair mechanisms should have played an important role in the maintenance of the structural integrity of primitive nucleic acids. 2,6‐Diaminopurine is a prebiotic nucleobase that repairs CPDs with high efficiency when incorporated into polymers. We investigate the electronic deactivation pathways of 2,6‐diaminopurine‐2′‐deoxyribose and 9‐methyl‐2,6‐diaminopurine in acetonitrile and aqueous solution to shed light on the photophysical and excited state properties of the 2,6‐diaminopurine chromophore. Evidence is presented that both are photostable compounds exhibiting similar deactivation mechanisms upon the population of the S1(ππ* La) state at 290 nm. The mechanism involves deactivation through the C2‐ and C6‐reaction coordinates and >99% of the excited state population decays through nonradiative pathways involving two conical intersections with the ground state. The radiative and nonradiative lifetimes are longer in aqueous solution compared to acetonitrile. While τ1 is similar in both derivatives, τ2 is ca. 1.5‐fold longer in 2,6‐diaminopurine‐2′‐deoxyribose due to a more efficient trapping in the S1(ππ* La) minimum. Therefore, 2,6‐diaminopurine could have accumulated in significant quantities during prebiotic times to be incorporated into non‐canonical RNA and play a significant role in its photoprotection. [ABSTRACT FROM AUTHOR]

Organic fluorophores with dual-state emission (DSE) are rare or difficult to observe because most of them display either aggregation-induced emission (AIE) or aggregation-caused quenching (ACQ). Amazing works have been accomplished, yet most of the DSE compounds were excited by UV light which limits their wide application in bioimaging. In this work, we achieved a visible-light excited DSE fluorophore and realized its imaging in SKOV-3 cells and zebrafish. The naphtho[2',3':4,5]imidazo[1,2-a]pyridine (NIP) core ensures its emission in dilute solution. Meanwhile, the twisted phenyl ring blocks fluorescence quenching induced by the π-π stacking and leads to the emission of the solid. The fluorescence intensity is steady even after 6 h of continuous intense sunlight. More importantly, photostability of NIP in cells is much better than commercial dye (mitochondrial green). [ABSTRACT FROM AUTHOR]

A new approach to the synthesis of derivatives of the perchlorinated tritryl radical is described. It relies on the fact that, under the conditions required to fully chlorinate the ortho positions of a triarylmethane, there is only minimal substitution of aryl fluorine by chlorine and then on the fact that, in the mixed Cl/F substituted triarylmethanes obtained, it is possible to selectively substitute the fluorine‐bearing positions using the sodium salt of n‐hexanol in n‐hexanol/dimethylsulfoxide. The meta‐hexyloxy derivatives obtained are much more soluble and photostable than the parent perchlorotrityl radical. For example, the introduction of four meta‐hexyloxy substituents gives a radical where, under white light illumination, the lifetime is improved by a factor of almost 104. The photostability of the radical, the lifetime of the excited state and the fluorescence all decrease as the number of meta‐hexyloxy substituents is increased. The improvements in solubility and in photostability observed should help in creating a more diverse range of perchlorotrityl radical derivatives and in the development of new applications. [ABSTRACT FROM AUTHOR]

With the rapid increase in power conversion efficiency of organic photovoltaics due to the development of non‐fullerene acceptors (NFAs), prolonging the operational lifetime of devices becomes one of the critical prerequisites for commercial application. In this work, the degradation pathways of a wide range of state‐of‐the‐art NFA molecules via multiple spectroscopic techniques combined with density functional theory and molecular dynamics simulation are revealed. The structural confinement and molecular ordering are responsible for molecular conformational stability under illumination. More importantly, a very general trend is revealed that the origin of increased nonradiative decay under illumination is predominately in the aggregated states with strong intermolecular interactions while the intramolecular exciton dynamics are stable. The increased nonradiative decay correlates with reduced exciton diffusion length. This work provides vital information toward the design of intrinsically photo‐stable NFAs at the molecular level and the importance of aggregation control toward long‐term stable organic solar cells. [ABSTRACT FROM AUTHOR]

Photo‐induced halide segregation in wide‐bandgap (WBG) perovskite leads to poor stability and limits its application in high‐efficiency tandem solar cells. Here, a simple solution strategy to achieve photostable WBG perovskite solar cells (PSCs) with bandgap of ≈1.67 eV by ionic coupling potassium sorbate with defects at the buried perovskite interface is reported. Moreover, the ionic coupled potassium sorbate (ICPS) enables to control the formation of N‐methyl formamidinium ions that can selectively passivate the perovskite defects at grain boundaries. As a result, the photo‐induced halide segregation in the target perovskite films is frozen under intense light. The target single‐junction WBG PSC achieves a record efficiency of 22.00% with an open‐circuit voltage (VOC) of 1.272 V and photostability of less than 2% decay over 2000 h of operation. Perovskite/Silicon tandem solar cells are also fabricated that achieve an efficiency of 30.72% (certified 30.09% @1.087 cm2), which is the highest efficiency reported to date with a tunneling oxide passivating contact (TOPCon) c‐Si substrate. The encapsulated tandem device can maintain 97% of its initial efficiency after 1000 h of operation. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiOX) is a desirable hole‐transporting material for perovskite solar cells owing to their merits of low‐cost, stable, and readily scalable. However, the NiOX|perovskite interface suffers from serious recombination and poor photostability because of the interfacial redox reactions. Herein, NiOX nanoparticles with tunable size have been synthesized at low temperatures by controlling the reactivity of the hydrolysis reaction. A self‐assembled monolayer composed of a ruthenium complex, i.e., C106, is then introduced to optimize the interfacial properties. The C106 molecule chemically bonds to NiOX via carboxyl acid group, which passivates the surface defects of NiOX and suppresses the negative redox reaction at the interface. The modification leads to an improvement in perovskite film morphology, crystallization, and band alignment. As a result, the efficiency of solar cells has been improved from 18.1% to 20.5%. More importantly, the modified solar cells retain >80% of their initial performance after continuous operation under 100 mW cm−2 irradiation for 800 h, which is much enhanced than the unmodified devices. [ABSTRACT FROM AUTHOR]

Lanthanides have unique photoluminescence (PL) emission properties, including very long PL lifetimes. This makes them ideal for biological imaging applications, especially using PL lifetime imaging microscopy (PLIM). PLIM is an inherently multidimensional technique with exceptional advantages for quantitative biological imaging. Unfortunately, due to the required prolonged acquisitions times, photobleaching of lanthanide PL emission currently constitutes one of the main drawbacks of PLIM. In this study, we report a small aqueous‐soluble, lanthanide antenna, 8‐methoxy‐2‐oxo‐1,2,4,5‐tetrahydrocyclopenta[de]quinoline‐3‐phosphonic acid, PAnt, specifically designed to dynamically interact with lanthanide ions, serving as exchangeable dye aimed at mitigating photobleaching in PLIM microscopy in cellulo. Thus, self‐assembled lanthanide complexes that may be photobleached during image acquisition are continuously replenished by intact lanthanide antennas from a large reservoir. Remarkably, our self‐assembled lanthanide complex clearly demonstrated a significant reduction of PL photobleaching when compared to well‐established lanthanide cryptates, used for bioimaging. This concept of exchangeable lanthanide antennas opens new possibilities for quantitative PLIM bioimaging. [ABSTRACT FROM AUTHOR]

Pinosylvin monomethyl ether (PsMME) is a natural compound known for its valuable bioactive properties, including antioxidant and anti-inflammatory effects. However, PsMME's susceptibility to photodegradation upon exposure to ultraviolet (UV) radiation poses a significant limitation to its applications in the pharmaceutical field. This study, for the first time, introduces a strategy to enhance the photostability of PsMME by employing various nanoformulations. We utilized mesoporous silica nanoparticles (MSNs) coated with polydopamine via a poly(ethylene imine) layer (PDA–PEI–MSNs), thermally carbonized porous silicon nanoparticles (TCPSi), and pure mesoporous polydopamine nanoparticles (MPDA). All these nanocarriers exhibit unique characteristics, including the potential for shielding the drug from UV light, which makes them promising for enhancing the photostability of loaded drugs. Here, these three nanoparticles were synthesized and their morphological and physicochemical properties, including size and ζ-potential, were characterized. They were subsequently loaded with PsMME, and the release profiles and kinetics of all three nanoformulations were determined. To assess their photoprotection ability, we employed gas chromatography with a flame ionization detector (GC-FID) and gas chromatography–mass spectrometry (GC-MS) to assess the recovery percentage of loaded PsMME before and after UV exposure for each nanoformulation. Our findings reveal that MPDA exhibits the highest protection ability, with a remarkable 90% protection against UV light on average. This positions MPDA as an ideal carrier for PsMME, and by extension, potentially for other photolabile drugs as well. As a final confirmation of its suitability as a drug nanocarrier, we conducted cytotoxicity evaluations of PsMME-loaded MPDA, demonstrating dose-dependent drug toxicity for this formulation. [ABSTRACT FROM AUTHOR]

The photooxidative stability of a series of doubly bridged anthracenes was evaluated after their preparation via twofold macrocyclization of a bis(resorcinyl)anthracene. Lightfastness correlates with the energy levels of the highest occupied molecular orbital (HOMO), resulting in superior stability of the tetraesters compared to the tetraethers. The lengths and steric demand of the linker only plays a minor role for the ester‐based compounds, which can be prepared in reasonable yields and thus tested in proof‐of‐concept organic light‐emitting diodes. Double ester‐bridging allows deep blue electro‐luminescence, highlighting the importance of the choice of the functional groups used for macrocyclization. [ABSTRACT FROM AUTHOR]

This research delvedinto the BrilliantBlue FCF (BB) dye encapsulation within the nano hydrophobic cavity of β‐cyclodextrin (β‐CD) utilizing various spectroscopic and physicochemical techniques. Job's plot using UV‐visible and Fluorescence spectroscopy, surface tension, and conductance study confirmed 1 : 1 stoichiometry of theinclusion complex (BBIC).1H NMR and FT‐IR studies demonstrated the possible binding mode of BB into the β‐CD cavity, which wasin good agreement withthe DFT study. The degree of affinity of β‐CD for BB in the ground state and excited state were estimatedfromUV‐visible andFluorescence spectroscopy(binding constant=8113.9451 M−1and10199.563 M−1), andthe negative free binding energyshowedthe encapsulation process to bethermodynamically feasible. PXRD analysis and SEM image studies revealed the formation of the BBIC. After complexation with β‐CD, the photostability of BB was found to be enhanced. The interaction study of BB and BBIC with CT‐DNA revealed the sustained release of BB from the complex. Furthermore, neither BBICnor free BB exhibited a significant cytotoxic effect on the normal cell line HEK‐293. However, BBIC complex (IC50=6.15 μM) showed significant in vitrocytotoxic activity compared to pure BB (IC50=8.90 μM) towards cancer cell line A549. [ABSTRACT FROM AUTHOR]

Fluorescent probes are essential for single‐molecule imaging. However, their application in biological systems is often limited by the short photobleaching lifetime. To overcome this, we developed a novel thiolation strategy for squaraine dyes. By introducing thiolation of the central cyclobutene of squaraine (thio‐squaraine), we observed a ≈5‐fold increase in photobleaching lifetime. Our single‐molecule data analysis attributes this improvement to improved photostability resulting from thiolation. Interestingly, bulk measurements show rapid oxidation of thio‐squaraine to its oxo‐analogue under irradiation, giving the perception of inferior photostability. This discrepancy between bulk and single‐molecule environments can be ascribed to the factors in the latter, including larger intermolecular distances and restricted mobility, which reduce the interactions between a fluorophore and reactive oxygen species produced by other fluorophores, ultimately impacting photobleaching and photoconversion rate. We demonstrate the remarkable performance of thio‐squaraine probes in various imaging buffers, such as glucose oxidase with catalase (GLOX) and GLOX+trolox. We successfully employed these photostable probes for single‐molecule tracking of CD56 membrane protein and monitoring mitochondria movements in live neurons. CD56 tracking revealed distinct motion states and the corresponding protein fractions. This investigation is expected to propel the development of single‐molecule imaging probes, particularly in scenarios where bulk measurements show suboptimal performance. [ABSTRACT FROM AUTHOR]

Camptothecin (CPT) is a potential anticancer drug. However, it faces challenges due to its poor water solubility and the need for an efficient drug release system. Herein, we developed a novel system composed of gelatin stabilized, mesoporous silica SBA15 encapsulated CuInS2/ZnS (CIS/ZnS) quantum dots (QDs) conjugated with β-cyclodextrin (β-CDs) for its potential use in the release of CPT. In this multifunctional system, β-CDs served as the drug carrier, SBA15 encapsulated QDs is capable of imaging and the gelatin was used to enhance the carrier-drug interaction. Fourier transform infrared (FTIR) analysis confirmed the successful conjugation of β-CDs to the Gel-SBA15 CIS/ZnS QDs, while optical analyses revealed excellent emission properties and high photostability. The β-CD-conjugated Gel-SBA15-CIS/ZnS QD nanocomposite was used to obtain the soluble derivate of CPT which further demonstrated a drug release profile following the triphasic model. Overall, the improved photostability and acceptable drug release profile of the β-CD conjugated Gel-SBA15-CIS/ZnS QD nanocomposite hold great promise for both imaging and therapeutic applications. [ABSTRACT FROM AUTHOR]

The high power-conversion efficiencies of hybrid perovskite solar cells encourage many researchers. However, their limited photostability represents a serious obstacle to the commercialization of this promising technology. Herein, we present an efficient method for improving the intrinsic photostability of a series of commonly used perovskite material formulations such as MAPbI3, FAPbI3, Cs0.12FA0.88PbI3, and Cs0.10MA0.15FA0.75PbI3 through modification with octenidine dihydroiodide (OctI2), which is a widely used antibacterial drug with two substituted pyridyl groups and two cationic centers in its molecular framework. The most impressive stabilizing effects were observed in the case of FAPbI3 and Cs0.12FA0.88PbI3 absorbers that were manifested in significant suppression or even blocking of the undesirable perovskite films' recrystallization and other decomposition pathways upon continuous 110 mW/cm2 light exposure. The achieved material photostability—within 9000 h for the Oct(FA)n−1PbnI3n+1 (n = 40–400) and 20,000 h for Oct(Cs0.12FA0.88)n−1PbnI3n+1 (where n = 40–400) formulations—matches the highest values ever reported for complex lead halides. It is important to note that the stabilizing effect is maintained when OctI2 is used only as a perovskite surface-modifying agent. Using a two-cation perovskite composition as an example, we showed that the performances of the solar cells based on the developed Oct(Cs0.12FA0.88)399Pb400I1201 absorber material are comparable to that of the reference devices based on the unmodified perovskite composition. These findings indicate a great potential of the proposed approach in the design of new highly photostable and efficient light absorbers. We believe that the results of this study will also help to establish important guidelines for the rational material design to improve the operational stability of perovskite solar cells. [ABSTRACT FROM AUTHOR]

Plexcitonic systems based on metal nanostructures and molecular J-aggregates offer an excellent opportunity to explore the intriguing interplay between plasmonic excitations and excitons, offering unique insights into light–matter interactions at the nanoscale. Their potential applications in photocatalysis have prompted a growing interest in both their synthesis and the analysis of their properties. However, in order to construct a high-performing system, it is essential to ensure chemical and spectral compatibility between both components. We present the results of a study into a hybrid system, achieved through the coupling of gold nanobipyramids with organic molecules, and demonstrate the strengthened photochemical properties of such a system in comparison with purely J-aggregates. Our analysis includes the absorbance and photoluminescence characterization of the system, revealing the remarkable plexcitonic interaction and pronounced coupling effect. The absorbance spectroscopy of the hybrid systems enabled the investigation of the coupling strength (g). Additionally, the photoluminescence response of the J-aggregates and coupled systems reveals the impact of the coupling regime. Utilizing fluorescence lifetime imaging microscopy, we established how the photoluminescence lifetime components of the J-aggregates are affected within the plexcitonic system. Finally, to assess the photodegradation of J-aggregates and plexcitonic systems, we conducted a comparative analysis. Our findings reveal that plasmon-enhanced interactions lead to improved photostability in hybrid systems. [ABSTRACT FROM AUTHOR]

Small molecule fluorophores often face challenges such as short blood half-life, limited physicochemical and optical stability, and poor pharmacokinetics. To overcome these limitations, we conjugated the zwitterionic near-infrared fluorophore ZW800-PEG to human serum albumin (HSA), creating HSA-ZW800-PEG. This conjugation notably improves chemical, physical, and optical stability under physiological conditions, addressing issues commonly encountered with small molecules in biological applications. Additionally, the high molecular weight and extinction coefficient of HSA-ZW800-PEG enhances biodistribution and tumor targeting through the enhanced permeability and retention effect. The unique distribution and elimination dynamics, along with the significantly extended blood half-life of HSA-ZW800-PEG, contribute to improved tumor targetability in both subcutaneous and orthotopic xenograft tumor-bearing animal models. This modification not only influences the pharmacokinetic profile, affecting retention time and clearance patterns, but also enhances bioavailability for targeting tissues. Our study guides further development and optimization of targeted imaging agents and drug-delivery systems. [ABSTRACT FROM AUTHOR]

Novel push–pull dicyanomethylenedihydrofuran(DCDHF)-based chromophores bearing 6-hydroxyl-2,5,7,8-tetramethylchroman-2-carboxylic acid (HTCX) group were synthesized to function as an antioxidant moiety. The preparation of phenylvinyl-bridged DCDHF chromophores with a hydroxyl functional group to be attached HTCX. Due to intramolecular charge transfer (ICT), HTCX-containing DCDHF chromophores showed a distinct solvatochromism in a range of organic solvents. The molecular structures of the prepared HTCX-bearing DCDHF fluorophores were verified by ¹H/13C NMR and FTIR spectroscopic analyses. The emission spectra demonstrated dramatic enhancement in the photostability of the prepared fluorophores. Though, the synthesized HTCX/LSHA(Light Stabilizer Hindered Amine)-DCDHF-based hybrids were studied to evaluated antimicrobial efficiency. HTCX-based hybrid DCDHF-8 revealed sensible activity towards (+ve) Gram and (-ve) Gram bacterial strains, and LSHA-based hybrid DCDHF-15 demonstrated good antibacterial effectiveness against B. cereus (+ve gram) and K. pneumoniae (-ve gram) bactria, comparative to Ampicillin reference. Moreover, the theoretical molecular docking stimulation was realistic to sight see their binding connections towards (PDB-1LNZ). [ABSTRACT FROM AUTHOR]

Aim/Background: The objective of this research was to develop a nano-emulsified formulation by using a central composite design for topical drug delivery. Materials and Methods: Isotretinoin-loaded nano-emulsified drug delivery system was prepared for topical application. Surface response methodology was used for the Design Of Experiment (DOE) using Central Composite Design (CCD). A combination of roseship and soyabean oil was used as the oil phase for the development of the formulation. Kolliphor® EL and Transcutol® P were used as surfactant and co-surfactant, respectively. The impact of independent parameters, percentage of oil phase (X1), and surfactant to co-surfactant ratio (X2) were checked at three levels of dependent variablesviz particle size and drug permeation. Results: p-value in ANOVA tables indicate a significant impact of both independent parameters on dependent parameters. R-sq and R-sq(adj) in both regressions is above 99%, confirming the model's suitability. The final formulation contains 22.07% of the oil phase. The ratio of surfactant and co-surfactant is 40:60. It helped to achieve a minimum particle size of ~280 nm and a maximum percentage permeation of ~70%. The optimized formulation was characterized for particle size, zeta potential, refractive index, polydispersity index, thermodynamic stability, and percentage drug permeation. Conclusion: The optimum percentage of the oil phase and surfactant to co-surfactant ratio improved the drug permeation when compared with the marketed formulation. [ABSTRACT FROM AUTHOR]

Abstract Single‐molecule localization microscopy has proved promising to unravel the dynamics and molecular architecture of thin biological samples down to nanoscales. For applications in complex, thick biological tissues shifting single‐particle emission wavelengths to the shortwave infrared (SWIR also called NIR II) region between 900 to 2100 nm, where biological tissues are more transparent is key. To date, mainly single‐walled carbon nanotubes (SWCNTs) enable such applications, but they are inherently 1D objects. Here, 0D ultra‐small luminescent gold nanoclusters (AuNCs,

The Cu2O/Cu emerges as a promising candidate for photocatalytic application owing to its efficient photon absorption in the visible light spectrum. However, the susceptibility of Cu2O-based photocatalysts to self-decomposition diminishes their effectiveness. This study introduces CoNi as co-catalyst to enhance the durability of Cu2O/Cu photocatalyst. Electrodeposition was employed to decorate the Cu2O/Cu crystal surface with Co, Ni and CoNi. The deposition potential of CoNi was optimized to produce a high-performance photocatalyst. The utilization of CoNi co-catalyst resulted in significant enhancements in photoelectrochemical properties under light irradiation when compared to using a single Co or Ni co-catalyst, suggesting a synergistic effect between Co and Ni within the system. The enhancement is evidenced by a noteworthy increase in the photocurrent of the photocatalyst, rising from 10.24 mA/cm2 to 20.81 mA/cm2. In addition, the decoration of CoNi resulted in a reduction of the charge transfer resistance from 4.2 kΩ to 0.7 kΩ, while simultaneously increasing the electrochemically active surface area of the photocatalyst from 15.49 cm2 to 157.69 cm2. The observed modifications lead to a substantial improvement in the photocatalytic efficiency, resulting in an impressive 88 % degradation of methylene blue, which is 3.4 times higher than achieved in the absence of the co-catalyst. Moreover, there was a significant improvement in the photostability of the photocatalyst, with an increase from 16.81 % to 50.55 %. These findings demonstrate the significance of CoNi co-catalyst decoration in producing a highly active and durable photocatalyst, making it a promising candidate for efficient synthetic dyes degradation.

Abstract High‐resolution spatio‐temporal monitoring of the cell membrane lipid order provides visual insights into the complex and sophisticated systems that control cellular physiological functions. Solvatochromic fluorescent probes are highly promising noninvasive visualization tools for identifying the ordering of the microenvironment of plasma membrane microdomains. However, conventional probes, although capable of structural analysis, lack the necessary long‐term photostability required for live imaging at the cellular level. Here, an ultra‐high‐light‐resistant solvatochromic fluorescence probe, 2‐N,N‐diethylamino‐7‐(4‐methoxycarbonylphenyl)‐9,9‐dimethylfluorene (FπCM) is reported, which enables live lipid order imaging of cell division. This probe and its derivatives exhibit sufficient fluorescence wavelengths, brightness, polarity responsiveness, low phototoxicity, and remarkable photostability under physiological conditions compared to conventional solvatochromic probes. Therefore, these probes have the potential to overcome the limitations of fluorescence microscopy, particularly those associated with photobleaching. FπCM probes can serve as valuable tools for elucidating mechanisms of cellular processes at the bio‐membrane level.

Abstract Electron shuttles are pivotal in enhancing the conversion efficiency at the biotic‐abiotic interface within microbial photoelectrochemical systems. Nevertheless, the potentially toxic effects of electron shuttles on microbial cells and their instability when exposed to light are often overlooked. This concept highlights the attention paid to electron shuttles in microbial photoelectrochemical systems, such as the cytotoxicity, the photoexcited state, and the photostability. Furthermore, it offers theoretical guidance for selecting electron shuttles to optimize sustainable energy production and environmental remediation.

The photodecomposition behavior of cationic porphyrin ZnTMAP4+ (zinc tetrakis-(N,N,N-trimethylanilinium-4-yl) porphyrin) in water and complexed with clay nanosheets was investigated by light irradiation to the Soret band of ZnTMAP4+. The decomposition of ZnTMAP4+ was observed by UV–visible absorption spectroscopy. While the decomposition quantum yield (ϕdec) was 3.4 × 10−4 in water, that was 9.4 × 10−7 on the exfoliated clay nanosheets. It was revealed that the photostability of ZnTMAP4+ was stabilized by the complex formation with clay. When ZnTMAP4+ was intercalated between the stacked clay nanosheets, ϕdec was further decreased to 4.9 × 10−7. The photostability increased by 361 times and 693 times for the exfoliated and stacked state, respectively. These results indicate that the flat clay surface has the potential to control intra- and intermolecular photochemical reactions.

Abstract Magnetic nanoparticles have shown promise in various medical applications, including cancer treatment and diagnostics. The objective of this study is to attain mastery over the synthesis of silver nanoparticles (AgNPs), Cobalt silver nanocomposite (CoAgNC) and magnetite silver nanocomposite (IOAgNC), while also examining their photostability, cytotoxicity, and photothermal impact on Human Laryngeal Carcinoma Cell line (HEp-2). The preparation and characterization of AgNPs, CoAgNC, and IOAgNC were described, including the assessment of their photostability and cytotoxicity on HEp-2 cell line. The photostability of these nanomaterials was determined by subjecting them to different light sources, while their morphology and magnetic properties were characterized using a spectrophotometer, Transmission Electron Microscopy (TEM), and Vibrating Sample Magnetometer (VSM). The results of the characterization of AgNPs, CoAgNC, and IOAgNC showed that the prepared nanomaterials have distinct optical and morphological properties. The synthesized nanomaterials were stable in aqueous solutions and exhibited magnetic properties. The cytotoxicity tests on HEp-2 cells showed that the nanomaterials were not toxic in the dark, but their toxicity increased under light exposure, with IOAgNC showing the most significant toxicity. CoAgNC was found to be photostable under UV light and Light Emitting Diode (LED) irradiation due to the little lattice mismatch between cobalt and silver. Nanocomposite systems of high magnetic moment, such as IOAgNC and CoAgNC, have potential for tumor treatment through magnetic fluid hyperthermia. The photostability, chemical stability, and biocompatibility of AgNPs, CoAgNC, and IOAgNC were investigated and found to be non-toxic even at high concentrations. These nanomaterials have multiple optical and magnetic functionalities and are promising candidates for biomedical applications.

In this work, we presented a study of the structural formula for a new series of complexes with Ag(I), Cu(II), Zn(II), and Cd(II) derived from the guanine azo dye ligand 2-amino-8-((3-hydroxyphenyl)diazinyl)-1,7-dihydro-6H-purin-6-one (HAG), which is investigated using various physicochemical analyses, spectroscopic techniques (FT-IR, U.V-VIS, and 1H NMR), thermogravimetric analysis (TGA). In addition, elemental analyses, magnetic susceptibility, and molar conductance measurements were all stabilized. As well as the mole ratio, stability constant, and Gibbs free energy were studied for all complexes, where they showed high stability and spontaneous synthesis. The Cu(II) complex was suggested to have octahedral stereochemistry, while the Ag(I), Zn(II), and Cd(II) complexes were suggested to have tetrahedral stereochemistry. The ligand has been demonstrated to be a useful acid-base indicator, and it has been shown that the ligand (HAG) and its complexes exhibit high photostability and have various colors that can be used to dye wool materials. [ABSTRACT FROM AUTHOR]

Comparison of photostability in degassed and aerated toluene solutions is reported for 5,10,15,20-tetraphenylporphyrin, 5,10,15-tri(p-tolyl)porphyrin, and their zinc analogues. After degassing, quantum yields of photodegradation are higher, but the photodecomposition rates decrease. Lower stability in deoxygenated solutions is due to much longer triplet lifetimes: 200–300 microseconds, compared to 200–360 ns in non-degassed toluene. For the zinc porphyrins, the LC–MS results show that the initial photoproduct contains two oxygen atoms. Based on electronic absorption and calculations, it is assigned to dehydrated zinc biladienone structure, relatively stable in toluene, but readily demetallated in dichloromethane. A similar species is formed also in the case of free bases, but it then undergoes hydration due to traces of water present in the solvent. Zinc derivatives were found to form biladienones even in degassed solutions. To explain this observation, we postulate formation of a complex with remaining oxygen or oxygen-containing species which is not removed by freeze–thaw procedure. This hypothesis is confirmed by MS results and by the analysis of photodegradation products obtained when zinc porphyrin is complexed with dimethylsulfoxide (DMSO). Under these circumstances, changes in absorption are the same as in the absence of DMSO when non-degassed toluene is used, but irradiation of deoxygenated solutions leads to a different photoproduct. For both degassed and non-degassed solvents, complexation with DMSO results in the enhancement of photostability. [ABSTRACT FROM AUTHOR]

The composites based on a semiconducting polymer and a modified fullerene were deposited as active layers of organic photovoltaic cells (OPCs). Fluorinated carbon nanotubes were added into the composite according to the procedure described previously [Kobeleva, E.S. et al., Fuller. Nanotub. 31, 464 (2023)]. The admixture inhibited photodegradation processes within OPC samples. This phenomenon is due to several reasons, in particular, the fixation of the optimal nanostructure of the bulk polymer : fullerene heterojunction and inhibition of the processes of morphological degradation of the active layer. [ABSTRACT FROM AUTHOR]

mCherry is one of the most successfully applied monomeric red fluorescent proteins (RFPs) for in vivo and in vitro imaging. However, questions pertaining to the photostability of the RFPs remain and rational further engineering of their photostability requires information about the fluorescence quenching mechanism in solution. To this end, NMR spectroscopic investigations might be helpful, and we present the near-complete backbone NMR chemical shift assignment to aid in this pursuit. [ABSTRACT FROM AUTHOR]

Theoretical study of the photophysical/photochemical properties of 1H‐benzimidazole and its derivatives was carried out using APFD, B3LYP, CAM‐B3LYP and PBE0 density functionals with 6‐311+G(2d,p) basis set. The effects of ethanol, 1,4‐dioxane, acetonitrile and water was investigated by means of Integral Equation Formalism of the Polarizable Continuum Model (IEPCM) in the framework of Self‐Consistent Reaction Field (SCRF). The results obtained show that S2 state of the 1H‐benzimidazole molecule is more acidic than the S0 state as the N5−H11 bond length increased to ~ 1.01 Å. At B3LYP/6‐311+G(2d,p) level of theory, the excitation energy of 1H‐bensimidazole molecule in ethanol from S0 to the S2 state was calculated to be 273 nm (4.54 eV). The electronic energy for this transition was calculated to be 0.131 a.u. and observed to occur between π→π* orbitals. Calculations with the PBE0, APFD and B3LYP functionals reproduced the experimental dipole moment in 1,4‐dioxane, with values of 4.09, 4.09 and 4.07 Debye respectively. However, the dipole moments of the 2‐ethyl‐7‐nitro‐5‐substituted‐1H‐benzimidazoles were calculated to be higher for electron donating groups (EDGs) than those bearing electron withdrawing groups (EWGs). In addition, the molecular polarizability was observed to increase with decreasing energy gap. Local excitation (LE) and charge‐transfer (CT) were observed to mediate the mechanisms of electronic excitation in 2‐ethyl‐7‐nitro‐5‐substituted‐1H‐benzimidazoles. [ABSTRACT FROM AUTHOR]

The development of low-cost and high-performance solar cells has become an important direction for the "dual carbon strategy". In this manuscript, we mainly describe the fabrication and characterization of novel inverted perovskite solar cells as well as a comprehensive chemistry experiment for undergraduates conceived to promote their scientific innovation and comprehensive practical abilities. This experiment encompasses the fabrication process of inverted perovskite solar cells, including transport layer fabrication, perovskite film, and electrode. The morphology and crystal quality of perovskite films were characterized by scanning electron microscope and X-ray diffractometer, and the current density and voltage (J-V) curves and photostability of the devices were tested using a solar simulator. The proposed experiment also integrates film preparation, material characterization, and device performance testing to meet different teaching needs. Simultaneously, the basic chemical principles in the experiment are taught to encourage students to further expand the experiment and provide a solid foundation for their future research and exploration. [ABSTRACT FROM AUTHOR]

The present study aimed to develop solid lipid nanoparticles of lutein (SLN/LT) with improved dissolution behavior and oral absorption. SLN/LT were prepared by a flash nanoprecipitation method using a multi-inlet vortex mixer, and their physicochemical, photochemical, and pharmacokinetic properties were evaluated. The mean particle size of SLN/LT re-dispersed in water was 237 nm, and small spherical particles with no significant aggregation were observed. LT significantly generated singlet oxygen upon exposure to pseudo-sunlight (250 W/m2, 1 h), suggesting its high photoreactivity. The remaining LT in LT solution, crystalline LT, and SLN/LT after irradiation with pseudo-sunlight (250 W/m2, 2 h) were 56.3, 86.7, and 101%, respectively. SLN/LT showed improved dissolution behavior of LT in simulated intestinal fluid, and the dissolved amounts of LT at 2 h were at least 50 times higher than that of crystalline LT. Orally administered SLN/LT (100 mg-LT/kg) exhibited enhanced oral absorption of LT, as evidenced by a relative bioavailability of 3.7 to crystalline LT in rats. SLN/LT may be a promising dosage form for orally available LT supplements, possibly leading to enhanced nutritional functions of LT. [ABSTRACT FROM AUTHOR]

Two gallium porphyrins, a tetraphenyl GaCl porphyrin, termed as (TPP)GaCl, and an octaethylporphyrin GaCl porphyrin, termed as (OEP)GaCl, were synthesized to use as an electron cascade in ternary organic bulk heterojunction films. A perfect matching of both gallium porphyrins' energy levels with that of poly(3-hexylthiophene-2,5-diyl) (P3HT) or poly[N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) polymer donor and the 6,6-phenyl C71 butyric acid methyl ester (PCBM) fullerene acceptor, forming an efficient cascade system that could facilitate electron transfer between donor and acceptor, was demonstrated. Therefore, ternary organic solar cells (OSCs) using the two porphyrins in various concentrations were fabricated where a performance enhancement was obtained. In particular, (TPP)GaCl-based ternary OSCs of low concentration (1:0.05 vv%) exhibited a ~17% increase in the power conversion efficiency (PCE) compared with the binary device due to improved exciton dissociation, electron transport and reduced recombination. On the other hand, ternary OSCs with a high concentration of (TPP)GaCl (1:0.1 vv%) and (OEP)GaCl (1:0.05 and 1:0.1 vv%) showed the poorest efficiencies due to very rough nanomorphology and suppressed crystallinity of ternary films when the GaCl porphyrin was introduced to the blend, as revealed from X-ray diffraction (XRD) and atomic force microscopy (AFM). The best performing devices also exhibited improved photostability when exposed to sunlight illumination for a period of 8 h than the binary OSCs, attributed to the suppressed photodegradation of the ternary (TPP)GaCl 1:0.05-based photoactive film. [ABSTRACT FROM AUTHOR]

This article presents a study on the photodegradation of beta-blocker drugs, with a specific focus on propranolol. The researchers used UV spectra to analyze the susceptibility of the drugs to degradation and employed chemometric approaches to determine the number of chemical components present in the samples. The study found that propranolol showed significant degradation and the formation of new products, possibly due to its unique chemical structure. The results provide valuable insights into the photodegradation mechanisms of beta-blocker drugs. The article also references other studies on photodegradation and stability analysis of pharmaceutical drugs. [Extracted from the article]

Comparative studies of the optical properties and photostability of pristine microsized TiO2 powder and modified with its own nano- and hollow particles have been carried out. It was established that the reflection coefficient (ρ) decreases down to 3.5% in the visible region and increases up to 3–4% in the near-IR region at a 3 wt% concentration of nano- and hollow TiO2 particles. Powders irradiation with intensive solar radiation causes an appearance of absorption bands with maxima at 420 nm and 800–1200 nm in the difference diffuse reflection spectra. In the spectra of the powder modified with hollow particles, the bands with lower intensity shift to shorter wavelengths—to 410 and 750–800 nm. An increase in irradiation time from 5 to 40 h results in the intensity increasing of such bands. It was found that a greater effect was obtained upon modification with hollow particles in comparison with TiO2 nanoparticles. Photostability of the powders modified with hollow particles is more than 4.6 times higher than for unmodified one and it was compared with powders modified with SiO2 and ZrO2 nanoparticles. An explanation of the results obtained is given. [ABSTRACT FROM AUTHOR]