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In this paper, the complex Eu (HFA)4TPP (HFA=Hexafluoroacetylacetone, TPP= tetraphenylphosphonium) with high photoluminescence quantum yield and improved stability is prepared. The steric effect on luminescence performance is revealed by studying the crystal structures and luminescence properties of Eu(HFA)4Na and Eu(HFA)4TPP complexes. On this basis, the luminescent films are obtained by incorporating Eu(HFA)4TPP complex with high loading content into polymethyl methacrylate (PMMA) matrix, which shows a visible-light excitation window (240~450 nm) and high photoluminescence quantum yield of 60. 54%. In addition, the luminescent solar concentrators (LSC) in Eu(HFA)4TPP/PMMA film conformation is prepared. The optical conversion efficiency contribution of Eu(HFA)4TPP/PMMA film to the LSC is 0. 95% in the case of the G=1. 87, holding promise in photovoltaic fields. [ABSTRACT FROM AUTHOR]

Propranolol (PPN) is widely used in children to treat various cardiovascular diseases. The availability of a suitable PPN solution should avoid recourse to extemporaneous preparations of unknown/limited stability, as commonly made in hospital pharmacies. However, the development of pediatric PPN solutions is hindered by their instability to light and stability at pH ≈ 3, bitter taste, and the need to improve palatability and avoid co-solvents, flavoring agents, or preservatives that are potentially toxic. In this study, cyclodextrin (CD) complexation has been exploited to develop a safe, stable, and palatable oral pediatric solution of PPN. An initial screening among various CDs allowed us to select HPβCD for its good complexing ability and no toxicity. Drug-HPβCD physical mixtures or co-ground systems (1:1 or 1:2 mol:mol) were used to prepare 0.2% w/v drug solutions. Photo stability studies evidenced the protective effect of HPβCD, revealing a reduction of up to 75% in the drug degradation rate after 1 h of exposure to UV radiation. Storage stability studies showed unchanged physical–chemical properties and almost constant drug concentration after 6 months and under accelerated conditions (40 °C), despite the less aggressive pH (≈5.5) of the solution. The electronic tongue test proved that the HPβCD taste-masking properties improved the formulation palatability, with a 30% reduction in drug bitterness. [ABSTRACT FROM AUTHOR]

Self assembly is that the ability of the biological entities to join with one another to form supramolecular structures. Such basic self assembled structures of peptides and amino acids to nanotubes, nanovesicles and nanorods are studied well. Here it is accounted completely as an uniquecategory of self-assembled N‑(3,5-bis-trifluoromethyl) benzyl-2-amino-3-phenyl propanamide (BTBP) nanotubes behaves like classic dipeptides. Characterization techniques viz., UV–Vis, UV-DRS, XRD, SEM, AFM, and TEM are accustomed to perceive the structure of these benzylamine derived amino acid (BTPNTs) nanotubes.The obtained self assembly is tested for its economical water filtration ability supported by its tubular structure. It is found that these nanotubes are extremely photo stable and removing poisonous metals by sorption and filtration. Hence the results provided a brand new data relating to the water filtration at cheap duplicated storable novel material. In the current study the portrayal of self-assembled BTPNTs covered separating material BTFM shows various benefits in the water filtration measure is proposed. Interestingly the benzylamine subsidiary of single amino acid phenyl alanine is a novel light responsive, productive adsorbent and filtering material to eliminate the natural toxins and hardness producing is exposed. This investigations like XRD, UV-DRS, SEM, AFM, and TEM are further supports the mechanism of the findings. Hence it is proposed as affordable water cleanup material in future technology which is warranted in this pandemic time. The results shoes that the self assembled nanotubes coated filter paper is ideal for providing clean water in terms of the removal of hardness and poisonous materials. The reusability of the proposed material is being tested and seems to be promising. [ABSTRACT FROM AUTHOR]

In the past decade, there has been a rapid development in perovskite solar cells, and their highest device efficiency has reached 25.7%. But their poor stability is still one of the critical factors hindering commercialization. Compared with 3D‐structured perovskites, 2D perovskites have better structural stability especially 2D Dion−Jacobson (D–J) perovskites. However, their degradation mechanism under light is not clear. Herein, the changes in the absorption spectra of D–J perovskites (PDA(FA)n−1PbnI3n−1) under continuous light illumination (100 mW cm−2) are investigated. The absorption spectra of D–J perovskites with different n values change in different degrees after two hours of continuous light illumination. It is found that the absorption intensity near the band edge of all these films has been enhanced, which indicates that some more absorbing species are produced. X‐Ray diffraction patterns confirm that the PDA(FA)n−1PbnI3n−1 2D D–J perovskite is transformed into 3D α‐FAPbI3 after illumination, and further transformed into δ‐FAPbI3 and PbI2. The proposed work contributes to understanding the degradation mechanism of 2D D–J perovskite under illumination and improving the stability of 2D D–J perovskite materials. [ABSTRACT FROM AUTHOR]

In recent years, halide perovskite quantum dots (HP-QDs) based composites have been widely developed and used in various applications owing to their unique photonic, electronic and mechanical properties, as well as high stability to water, oxygen, heat and illumination. Remarkable efforts have been made in the synthesis and applications of these materials in photonics, electronics, sensors and other fields. Besides these topics, we also cover enhancement of optoelectronic properties as well as chemical, thermal and photostability of HP-QDs-based composites. We hope this review will promote both the development and applications of perovskite-based materials.

We present the latest status of high performance OLED material development based on conjugated polymer technologies. The material which shows high performance is very suitable for printed OLED panel fabrication. New materials to reduce degradation from exciton realized better device lifetime. New materials which show PL spectrum with narrow line width and suitable peak wavelength have been developed to improve efficiency by enhancing the outcoupling on top‐emission (TE) devices. [ABSTRACT FROM AUTHOR]

We present the latest status of high performance OLED material development based on conjugated polymer technologies. The material which shows high performance is very suitable for printed OLED panel fabrication. New materials to reduce degradation from exciton realized better device lifetime. Key parameters have been identified to achieve high performance of ink jet printed (IJP) device. New materials for higher resolution panel fabrication have been developed and they provide wider application of IJP devices. [ABSTRACT FROM AUTHOR]

ZnS QDs were synthesized by chemical co precipitation method and then embedded in polyvinyl alcohol (PVA) with different concentrations of ZnS. The samples of ZnS/PVA were characterized by X-ray diffraction (XRD), transmission electron microscopy and Scanning Electron Microscopy. The XRD study showed that the crystallite size was around 9 nm. UV/VIS optical spectroscopy studies were used to determine the energy band gap of ZnS/PVA nanoparticles films against the increase of concentration. The photo stability of QDs ZnS/PVA composites are highlighted. The photo stability rate was enhanced to 48% after 420 min for UV–VIS irradiation. The nanocomposite ZnS/PVA has the optimum properties as a proper candidate for flat panel display, LED and solar collector. [ABSTRACT FROM AUTHOR]

We present the latest status of high performance OLED material development based on conjugated polymer technologies. The material which shows high performance is very suitable for printed OLED panel fabrication. New emitter development has realized better outcoupling on top‐emission device and wider color gamut. Key parameters have been identified to achieve high performance of ink jet printed (IJP) device. New materials for higher resolution panel fabrication have been developed and they provide wider application of IJP devices. [ABSTRACT FROM AUTHOR]

In recent years, halide perovskite quantum dots (HP-QDs) based composites have been widely developed and used in various applications owing to their unique photonic, electronic and mechanical properties, as well as high stability to water, oxygen, heat and illumination. Remarkable efforts have been made in the synthesis and applications of these materials in photonics, electronics, sensors and other fields. Besides these topics, we also cover enhancement of optoelectronic properties as well as chemical, thermal and photostability of HP-QDs-based composites. We hope this review will promote both the development and applications of perovskite-based materials. [ABSTRACT FROM AUTHOR]

We present the latest status of high performance OLED material development based on conjugated polymer technologies. The material which shows high performance is very suitable for printed OLED panel fabrication. New emitter development has realized better outcoupling on top‐emission device and wider color gamut. Key parameters have been identified to achieve high performance of ink jet printed (IJP) device. New materials for higher resolution panel fabrication have been developed and they provide wider application of IJP devices. [ABSTRACT FROM AUTHOR]

Fluorescein itself is a synthetic organic compound and a prominent member of the xanthene dye family. It exhibits strong fluorescence under ultraviolet (UV) or blue light excitation, making it widely used in various applications, including fluorescence microscopy, flow cytometry, immunoassays, and molecular biology techniques. One of the reasons fluorescein derivatives are highly valuable is their tunable fluorescence properties. Through chemical modifications of the fluorescein structure, different functional groups or substituents can be introduce, altering the compound's fluorescence characteristics such as emission wavelength, intensity, and photo stability. This flexibility allows for tailoring of fluorescent probes to specific experimental requirements, enhancing their utility in a range of scientific disciplines. Fluorescein derivatives also possess excellent antimicrobial and antioxidant activity. This review sheds light on the significant impact of fluorescein derivatives as biological active compounds, highlighting their potential in designing new therapeutic agents with antimicrobial properties. Additionally, their role as antioxidants is discussed. A major aspect covered in the review is the application of fluorescein derivatives as powerful cell imaging probes. Their unique fluorescent properties make them valuable tools for visualizing cellular structures and processes, opening up new possibilities for studying cellular dynamics and interactions. [Display omitted] • Significant impact of fluorescein derivatives as biologically active compounds. • Potential for designing new antimicrobial therapeutic agents. • Extensive discussion on their role as antioxidants in combating oxidative stress. • Application as powerful cell imaging probes for visualizing cellular structures and processes. • Utilization as highly selective and sensitive sensors for detecting anions, cations, and neutral compounds. [ABSTRACT FROM AUTHOR]

Abstract Irradiation with intense blue LED light of Lumogen orange 240 (1) in non-reactive solvents led to bleaching. The products of these photochemical reactions were not possible to determine. Contrarily, irradiation in ethanol or propanol led to red color shifts caused by the formation of the ethoxy or propoxy derivative of Lumogen orange 240, respectively. These new reaction products are only formed when both light and oxygen are present. A possible mechanism for these photo-oxidation reactions, the implication for the stability of perylene type of fluorescent dyes under LED lamp conditions and possible preparative applications are discussed. [ABSTRACT FROM AUTHOR]

In this work, we synthesis a new electron-transporting layer material for inverted organic solar cells(i-OSCs) based on organosilica nanodots. The material is synthesized by a simple one-step hydrothermal reaction of 3-[2-(2-aminoethylamino)ethylamino] propyl-trimethoxysilane (AEEA) with carminic acid in water solvent (OSi-CA). Compared with ZnO-based devices, OSi-CA based devices show improved carrier extraction, higher PCE, and greatly increased device stability under UV irradiation. With PM6:Y6 as the active layer, OSi-CA based device has a PCE of 16.01 %. In addition, the OSi-CA electron-transporting layer significantly improves the photostability of OSCs. After 600 min of continuous UV lamp (5 mW cm−2) irradiation, the OSi-CA based i-OSC retained 95.5 % of its initial performance, whereas the ZnO-based device had only 71.2 %. [Display omitted] • A cost-effective organosilica nanodots (OSi-CA) aqueous solution with one-step processing has been prepared. • The PCE reaches 16.01 % by using the organosilica nanodots (OSi-CA) as cathode interlayer. • 95.5 % initial efficiency was maintained under 600 min continuous UV illumination. [ABSTRACT FROM AUTHOR]

Abstract Fluorescent InP-based quantum dots (QDs) have attracted much attention as materials for display applications. Over the past few years, persistent effort has focused on improving photoluminescence (PL) quantum yields and narrowing PL bandwidths through synthesis; as a consequence, the PL properties of InP-based QDs are now comparable to of those of CdSe QDs. Unfortunately, the lack of PL stability in degradable environments has hindered investigations into the applications of these materials. Herein, we report the synthesis of green-emitting In(Zn,Ga)P/ZnSeS/ZnS small-core/thick-multishell QDs that exhibit 78% of the maximum PL quantum yield. Zn and Ga impurities in the InP-QD cores reduce the lattice constant of the InP QDs, which facilitates the growth of thick ZnSeS/ZnS shells. Due to protection of the QD exciton, which is spread away from the surface of the In(Zn,Ga)P/ZnSeS (core/shell) structure by the perfect passivating properties of the thick ZnS shell, the green-emitting In(Zn,Ga)P/ZnSeS/ZnS (core/multishell) QDs are significantly more photostable than In(Zn,Ga)P/ZnSeS QDs. A close-packed QD film displayed bright green (532 nm) emission with suppressed concentration quenching, which is useful for environmentally friendly QD-based displays. [ABSTRACT FROM AUTHOR]

The demand for bioactive molecules, such as ß- carotene (ß-car), has increased, but some characteristics such as low water solubility and low photo stability limit its application in many formulations. The bioactive entrapment into milk proteins may overcome this barrier. Thus, the aim of this work was to study the interaction between ß-car and bovine serum albumin (BSA) or ß-casein and the photo stability of this bioactive in the presence of the proteins. Fluorescence spectroscopy showed that at pH 7.0, increasing concentrations of ß-carotene reduced the fluorescence intensity of both proteins, and the fluorescence-quenching mechanism is mainly static. The stoichiometry of the ß-car/protein complex varied between proteins, being 1:1 to native BSA, 1:3 to denatured BSA (d-BSA), and 1:2 for ß-casein. The standard Gibbs-free energy (ΔG°) of complex formation was negative for all systems studied and followed the order ΔG°BSA <ΔG°ß-casein <ΔG°d-BSA. The formation of ß-car/protein complex was driven by entropy increasing in all studied conditions. Both proteins improved ß-car photo stability, but ß-casein micelle was more efficient, reducing and increasing four times, respectively, the bioactive degradation constant and the halftime of ß-car. The overall results pointed to the strategic use of milk proteins, especially ß-casein micelles as nanovehicle for ß-car in food and other systems. [ABSTRACT FROM AUTHOR]

Five novel triarymethine derivatives containing a two chromophore moiety within the molecule have been designed, synthesized and investigated as potential color filter dyes. These new “dimer-type” triarylmethines showed increased photostability and thermal stability compared to the Victoria Blue BO unit and notably manipulation of the dye counter ion also led to increased thermal stability. To evaluate the dyes in color filters, filters were fabricated and the photo- and thermo-stability was determined after heat treatment (230 °C for 30 min). The fabricated color filters showed approximately 80% transmittance at 450 nm and the ΔE ab values were in the range 3.03–9.26. These results indicate that the synthesized dimer-type triarylmethine derivatives have the potential for application as color filters for blue dyes. [ABSTRACT FROM AUTHOR]

Solution-processed small molecule-fullerene bulk heterojunction (SM BHJ) solar cells now have power conversion efficiency (PCE) greater than 10%. However, degradation of SM BHJ solar cells has not been well studied. This work reports the first stability study of six high performance molecules including the record SM BHJ solar cells under device operating conditions. Solar cells with a range of donor molecular weight from 1200 to 2300 Da giving 6–10% PCE are monitored in nitrogen gas under 1 sun illumination with maximum power point tracking as well as at 25 °C and 70 °C in the dark. Both heat and light contribute to initial exponential decay or burn-in with total reduction in efficiency from 31% to 66%. Larger molecules are found to be resistant to heat induced burn-in, while more crystalline active layers are more resistant to light induced burn-in. After burn-in, the linear degradation is observed to be governed by thermal processes. Stabilized TS80 lifetimes of the SM BHJ solar cells range from 3450 h to 5600 h. Molecular design towards higher stability should aim at increasing thermal stability while maintaining crystallinity for photostability. [ABSTRACT FROM AUTHOR]

Wide bandgap MAPb(I1-yBry)3 perovskites show promising potential for application in tandem solar cells. However, unstable photovoltaic performance caused by phase segregation has been observed under illumination when y is above 0.2. Herein, we successfully demonstrate stabilization of the I/Br phase by partially replacing Pb2+ with Sn2+ and verify this stabilization with X-ray diffractometry and transient absorption spectroscopy. The resulting MAPb0.75Sn0.25(I1-yBry)3 perovskite solar cells show stable photovoltaic performance under continuous illumination. Among these cells, the one based on MAPb0.75Sn0.25(I0.4Br0.6)3 perovskite shows the highest efficiency of 12.59% with a bandgap of 1.73 eV, which make it a promising wide bandgap candidate for application in tandem solar cells. The engineering of internal bonding environment by partial Sn substitution is believed to be the main reason for making MAPb0.75Sn0.25(I1-yBry)3 perovskite less vulnerable to phase segregation during the photostriction under illumination. Therefore, this study establishes composition engineering of the metal site as a promising strategy to impart phase stability in hybrid perovskites under illumination. [ABSTRACT FROM AUTHOR]

Some derivatives of 3-ethyl-2-mercapto-thieno[2,3- d ]pyrimidin-4(3 H )-ones were synthesized using ethyl 2-aminothiophene-3-carboxylates as precursors in order to estimate their cytotoxicity, respectively proliferative activity. Thienopyrimidinones containing thiosemicarbazide as well as 1,3,4-thiadiazole moieties were evaluated for their cytotoxical effect on four cancer cell lines: HT-29, breast cancer cells MDA-MB-231, HeLa, HepG2 as well as human diploid cell line Lep-3. Compounds 5b , 6a and 6b revealed cytotoxicity to the four studied cancer cell lines. The highst cytotoxicity against MDA-MB-31 exhibited the thiosemicarbazide 5b with IC 50 2.31.10 −4 μM, but most active towards HT-29 cell lines was thienopyrimidine 6c with IC 50 0.001 μM. Compound 6 a showed the highest inhibitory activity with IC 50 - 0.99 μM to human liver carcinoma HepG2 cells and low cytotoxicity towards Lep3 (IC 50 = 191 μM). The thienopyrimidine derivative linked to thiadiazole 6b was toxic to the four studied cancer cell lines, especially to HeLa (IC50–0.83 μM), and besides that the compound demonstrated toxicity to Lep 3 cells at very high concentration 89 × 10 3 μM. The solid-state photostability of the derivatives 5a-c and 6a-c was tested by irradiation with UV light. All of the studied compounds show solid-state photostability in 240 min of irradiation. Using MOE software molecular docking of the three ligands 5b , 6b and 7 was accomplished into an internal pocket formed by the activation segment and the P-loop of V599E B-Raf. It was established that the binding of the ligands to V599E B-Raf promotes an inactive conformation of the enzyme. [ABSTRACT FROM AUTHOR]

The ultraviolet (UV) absorption spectra of the liquid crystalline dimer complexes of 4-n-alkoxycinnamic acids (nOCNA: n = 4, 6, 8, where n is the number of carbon atoms in the alkoxy chain) have been presented. The nOCNA structures have been optimized using the density functional Becke3-Lee-Yang-Parr (B3LYP) hybrid functional with 6-31 + G (d) basis set using the crystallographic geometry as input. The electronic structures of the dimer molecules have been evaluated using the optimized geometries. The spectra of the dimer molecules have been calculated by employing the density functional theory (DFT), semiempirical complete neglect of differential overlap/spectroscopy (CNDO/S), and intermediate neglect of differential overlap/spectroscopy (INDO/S) parameterizations. The features of electronic transitions and excited states have been calculated via configuration interaction singles (CIS) with the semiempirical Hamiltonian Zerner intermediate neglect of differential overlap (ZINDO). The effect of molecular interactions and the end chain length may be reasonably useful for the progress and efforts in developing the photo-addressed color displays. [ABSTRACT FROM AUTHOR]

Highlights: [•] P3HT–PCBM composites find application in bulk-hetero junction (BHJ) solar cells. [•] P3HT–PCBM degrade under UV-irradiation due to presence of oxygen and moisture. [•] Nanocomposites of P3HT–PCBM with MWCNT show very high photo stability. [•] Solution and film studies confirm excellent photo stability of P3HT–PCBM–MWCNT. [Copyright &y& Elsevier]

[Display omitted] • Monomers and polymers were synthesized with thiocarbohydrazone unit via condensation and oxidative, respectively. • The quantum yields of Poly-SATCH, Poly-MSATCH and Poly-NATCH were found to be 4.1%, 11.4% and 7.4%, respectively. • Poly-MSATCH was demonstrated multichromic properties such as white, blue, green and yellow emissions. In this study, a family of azomethine-based thiocarbohydrazone monomers and polymers prepared and their structurally characterized by FT-IR, 1H–13C NMR and UV–Vis techniques. The electrochemical behaviors, fluorescent activities, thermal characteristics, antioxidant effectiveness of synthesized compounds were determined by cyclic voltammetry (CV), fluorescence (FL) spectroscopy, thermogravimetric-differential thermal analysis (TG-DTA), differential scanning calorimeter (DSC) and CUPRAC techniques, respectively. Fluorescence quantum yields of Poly-SATCH, Poly-BSATCH, Poly-MSATCH, Poly-NATCH were calculated to be 4.1, 9.4, 11.4 and 7.4 % in 0.025 mg mL−1 concentrations in DMF solutions in the range of 3 nm slit at 440, 420, 400 and 340 nm, respectively. The antioxidant values of monomer and polymers were changed between 0.30 ± 0.029 and 3.54 ± 0.719 against CUPRAC technique. The glass transition temperatures of Poly-SATCH, Poly-BSATCH, Poly-MSATCH and Poly-NATCH were found to be 116, 134, 138 and 139, respectively. [ABSTRACT FROM AUTHOR]

Interface engineering is one of the promising strategies for the long-term stabilization of perovskite solar cells (PSCs), preventing chemical decomposition induced by external agents and promoting fast charge transfer. Recently, MXenes-2D structured transition metal carbides and nitrides with various functionalization (O, -F, -OH) have demonstrated high potential for mastering the work function in halide perovskite absorbers and have significantly improved the n-type charge collection in solar cells. This work demonstrates that MXenes allow for efficient stabilization of PSCs besides improving their performances. A mixed composite bathocuproine:MXene, that is, (BCP:MXene) interlayer, is introduced at the interface between an electron-transport layer (ETL) and a metal cathode in the p-i-n device structure. The investigation demonstrates that the use of BCP:MXene interlayer slightly increases the power conversation efficiency (PCE) for PSCs (from 16.5 for reference to 17.5%) but dramatically improves the out of Glove-Box stability. Under ISOS-L-2 light soaking stress at 63 ± 1.5 °C, the T80 (time needed to reduce efficiency down to 80% of the initial one) period increases from 460 to > 2300 hours (h)., (© 2022 Wiley-VCH GmbH.)

Abstract: Topical application of lutein as an innovative antioxidant, anti-stress and blue light filter, which is able to protect skin from photo damage, has got a special cosmetic and pharmaceutical interest in the last decade. Lutein is poorly soluble, and was therefore incorporated into nanocarriers for dermal delivery: solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and a nanoemulsion (NE). Nanocarriers were produced by high pressure homogenization. The mean particle size was in the range of about 150nm to maximum 350nm, it decreased with increasing oil content of the carriers. The zeta potential in water was in the range −40 to −63mV, being in agreement with the good short term stability at room temperature monitored for one month. In vitro release was studied using a membrane free model. Highest release in 24h was observed for the nanoemulsion (19.5%), lowest release (0.4%) for the SLN. Release profiles were biphasic (lipid nanoparticles) or triphasic (NE). In vitro penetration study with a cellulose membrane showed in agreement highest values for the NE (60% in 24h), distinctly lower values for the solid nanocarriers SLN and NLC (8–19%), lowest values for lutein powder (5%). Permeation studies with fresh pig ear skin showed that no (SLN, NLC) or very little lutein (0.4% after 24h) permeated, that means the active remains in the skin and is not systemically absorbed. The nanocarriers were able to protect lutein against UV degradation. In SLN, only 0.06% degradation was observed after irradiation with 10 MED (Minimal Erythema Dose), in NLC 6–8%, compared to 14% in the NE, and to 50% as lutein powder suspended in corn oil. Based on size, stability and release/permeation data, and considering the chemical protection of the lutein prior to its absorption into the skin, the lipid nanoparticles are potential dermal nanocarriers for lutein. [Copyright &y& Elsevier]

Degradation of liquid crystal cell under a blue-violet laser beam irradiation has been investigated for an evaluation of a LC cell photostability. The laser beam was focused on the LC layer in the cell. A far field pattern (FFP) was caused by the change of the LC alignment at the focused point after a few minutes irradiation. The FFP changed as a progress of the alignment degradation and it depended on LC materials, polymer materials and their combinations. [ABSTRACT FROM AUTHOR]