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The interest in research to enhance the ability of sensitizers to generate singlet oxygen using light and/or ultrasound in cancer treatment has increased significantly in recent years, and studies have attracted considerable interest. In addition, phthalocyanines (Pcs) have become increasingly important as sensitizers in photodynamic therapy (PDT) (stimulation source: light) and/or sonodynamic therapy (SDT) (stimulation source: light and ultrasound). Sonophotodynamic therapy (SPDT), a new technique that gives more effective results than PDT, is now gaining in importance. Although there are published articles on SPDT studies, studies in this field are limited. In this context, we synthesized a zinc(II) phthalocyanine molecule bearing 4-(pyridine-4-ylthio) substituents to determine its potential as a sensitizer in SPDT applications as well as PDT applications, and the structure of the synthesized complex was illuminated using FTIR,1H-NMR, UV-Vis, and MS spectroscopic techniques. When light and ultrasound were combined, the calculated ΦΔ value for zinc (II) phthalocyanine (3) increased to greater than 1, even though it was 0.76 after light excitation. When evaluating the two methods, it was observed that singlet oxygen production was greatly enhanced by the SPDT method. In this way, the research will add to the enhancement of knowledge on the subject of the SPDT method's enhancement of singlet oxygen generation.

The operation of DSSC is similar to that of photosynthesis. This technology evolves from the concept of "artificial photosynthesis". Instead of chlorophyll, a light-absorbing dye is used in DSSCs. Generally, four categories of dyes include inorganic, organic, natural, and perovskite-based dyes. are used in DSSC. Replacing organic dyes in DSSCs with nature-friendly, biodegradable, and low-cost natural dyes paves the way for new opportunities in the commercialization of this technology. In this paper, we have investigated the use of various natural dyes as photosensitizers and the different parameters that improve cell efficiency. [ABSTRACT FROM AUTHOR]

ABSTRACT Dye‐sensitized solar cells (DSSCs) are considered a promising solution to current energy challenges. In this study, three porphyrin sensitizers ZnP1–ZnP3 with donor‐π‐acceptor (D‐π‐A) configurations were synthesized. The donors included 9,9‐dimethylfluorene, 4‐biphenyl, and 1,1′:3′,1″‐terphenyl groups, whereas alkynylbenzoic acid was used as the acceptor. The modification of the side alkyl chain addressed the poor solubility of the porphyrin sensitizer. The synthesized porphyrin sensitizers were structurally characterized by nuclear magnetic resonance, high‐resolution mass spectrometry, and ultraviolet absorption spectroscopy. The introduction of electron donor groups into 1,1′:3′,1″‐terphenyl and alkynylbenzoic acid into the acceptor group improved the light‐harvesting ability of the sensitizer, increased the short‐circuit photocurrent density, and enhanced cell efficiency (η = 3.6%). Finally, density functional theory was used to verify the experimental results. [ABSTRACT FROM AUTHOR]

Organic light‐emitting diodes (OLEDs) employing multi‐resonance (MR) emitters have attracted much attention due to their high luminescent efficiency and color purity, however, the development of deep‐blue multi‐resonance OLEDs is hindered by the lack of suitable sensitizers. Here a novel design strategy is reported for thermally activated delayed fluorescence sensitizer with high reverse intersystem crossing (kRISC) and radiative transition (kR) rate by regulating atom distribution of a spatially‐aligned carbazole donor/diphenylpyrimidine acceptor structure to manipulate through‐space charge transfer (CT) process. It is found that diphenylpyrimidine acceptor with 1,3‐position nitrogen atoms is un‐conjugated to bridging phenyl moiety by the conjugation node of pyrimidine, while the acceptor with 1,5‐position nitrogen atoms is conjugated to bridging phenyl through conjugation site, opening through‐bond CT pathway via bridging phenyl besides through‐space CT from spatial donor‐acceptor interactions. As a result, the sensitizer with 1,5‐position nitrogen atoms exhibits enhanced oscillator strength by 3.5 folds and accelerated kR of 3.57 × 107 s−1, while keeping high kRISC of 4.03 × 106 s−1 and high singlet (S1) state (2.88 eV). Solution‐processed OLEDs using the sensitizer and deep‐blue multi‐resonance emitter exhibit efficient narrowband electroluminescence with CIE coordinates of (0.14, 0.13) and EQEmax of 15.6%, representing the state‐of‐the‐art device performance for deep‐blue multi‐resonance OLEDs by solution process. [ABSTRACT FROM AUTHOR]

Co2+ and Ni2+ were investigated as potential sensitizers for the continuous flow UV-induced Hg vapor generation utilizing 10% (v/v) HCOOH as a low-molecular weight carboxylic acid and a modified multimode sample introduction system (MSIS) as a gas–liquid separator (GLS) coupled with microwave plasma atomic emission spectrometry (MP-AES). In contrast with Co2+, Ni2+ was found to suppress the sensitivity at different concentration levels. Thus, Co2+ was selected as a suitable sensitivity enhancement reagent and its concentration (1.50 mg dm−3) was optimized improving the empirical and the instrumental limit of detection (LOD) for Hg2+ to 0.10 µg dm−3 and 0.01 µg dm−3, respectively. The possible reasons for the observed effects of Co2+ and Ni2+ on the sensitivity were discussed. The Co2+—assisted UV-induced Hg vapor generation coupled with the modified MSIS GLS and MP-AES provided significantly lower instrumental LOD (ILOD) in comparison with other hyphenated Hg vapor generation procedures in the atomic spectrometry previously reported in the literature. [ABSTRACT FROM AUTHOR]

The interest in research to enhance the ability of sensitizers to generate singlet oxygen using light and/or ultrasound in cancer treatment has increased significantly in recent years, and studies have attracted considerable interest. In addition, phthalocyanines (Pcs) have become increasingly important as sensitizers in photodynamic therapy (PDT) (stimulation source: light) and/or sonodynamic therapy (SDT) (stimulation source: light and ultrasound). Sonophotodynamic therapy (SPDT), a new technique that gives more effective results than PDT, is now gaining in importance. Although there are published articles on SPDT studies, studies in this field are limited. In this context, we synthesized a zinc(II) phthalocyanine molecule bearing 4-(pyridine-4-ylthio) substituents to determine its potential as a sensitizer in SPDT applications as well as PDT applications, and the structure of the synthesized complex was illuminated using FTIR,1H-NMR, UV-Vis, and MS spectroscopic techniques. When light and ultrasound were combined, the calculated ΦΔ value for zinc (II) phthalocyanine (3) increased to greater than 1, even though it was 0.76 after light excitation. When evaluating the two methods, it was observed that singlet oxygen production was greatly enhanced by the SPDT method. In this way, the research will add to the enhancement of knowledge on the subject of the SPDT method's enhancement of singlet oxygen generation. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) remains one of the most common types of cancer, ranking fifth among cancer-related deaths worldwide. Chemotherapy is an effective treatment for advanced GC. However, the development of chemotherapy resistance, which involves the malfunction of several signaling pathways and is the consequence of numerous variables interacting, seriously affects patient treatment and leads to poor clinical outcomes. Therefore, in order to treat GC, it is imperative to find novel medications that will increase chemotherapy sensitivity and reverse chemotherapy resistance. Traditional Chinese medicine (TCM) has been extensively researched as an adjuvant medication in recent years. It has been shown to have anticancer benefits and to be crucial in enhancing chemotherapy sensitivity and reducing chemotherapy resistance. Given this, the mechanism of treatment resistance in GC is summed up in this work. The theoretical foundation for TCM as a sensitizer in adjuvant treatment of GC is established by introducing the primary signal pathways and possible targets implicated in improving chemotherapy sensitivity and reversing chemotherapy resistance of GC by TCM and active ingredients.

Triplet‐triplet annihilation upconversion (TTA‐UC) has made significant progress in recent years in several key applications, including solar energy harvesting, photocatalysis, stereoscopic 3D printing, and disease therapeutics. In TTA‐UC research, photosensitizers serve the vital function of harvesting low‐energy photons. The photophysical characteristics of photosensitizers, including absorbance, triplet state quantum yield, triplet state energy level, triplet state lifetime, etc. determine the performance of TTA‐UC. Thus, the study of photosensitizers has been a key aspect of TTA‐UC. In recent years, multi‐resonance thermally activated delayed fluorescence (MR‐TADF) molecules have received extensive attention due to their excellent photophysical properties and electroluminescent device performance. MR‐TADF molecules not only present a narrow energy gap between the singlet and triplet excited states, but also have stronger absorption and better wavelength regulation than conventional TADF molecules. Nowadays, the preliminary attempts in TTA‐UC using MR‐TADF molecules as photosensitizers have resulted in the development of green to ultraviolet, blue to ultraviolet, and even near‐infrared to blue emission. This concept will summarize the research progress of MR‐TADF molecules as photosensitizers in TTA‐UC, analyzing the challenges and giving possible solutions. Finally, we prospect the future development of MR‐TADF molecules as photosensitizers, including the molecular design as well as the possible application areas. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the value of Synechococcus 7942 (Syne) as a sensitizer for photo-sonodynamic therapy (PSDT). Syne was characterized. The efficacy of Syne-mediated PSDT were verified in vitro (in 4T1 breast cancer cells) and in vivo (in a breast tumor-bearing mouse model). The safety of Syne-mediated PSDT was verified in vivo. Results indicated that Syne triggered the generation of oxygen and ROS during PSDT, thereby inducing cell death in 4T1 cells. Syne-mediated PSDT induced the death of tumor cells both in vitro and in vivo. The speed of tumor growth was delayed in animals receiving PSDT. Syne-mediated PSDT was more effective than photodynamic therapy or sonodynamic therapy alone. In addition, administration of a Syne monomer resulted in satisfactory tumor targeting. Syne-mediated PSDT affected neither the animal body weight nor the major organs, indicating satisfactory safety. Accordingly, Syne is an efficient, safe, and readily available sensitizer that is ideal for potential clinical use of PSDT to treat breast cancer. The findings of this study are useful for exploration of a novel sensitizer for PSDT, which might be a promising alternative therapy against breast cancer. [ABSTRACT FROM AUTHOR]

A sensitizer or crosslinking promoter must be utilized to improve electron beam irradiation (EBI) vulcanization and achieve optimal results. This work investigated the effect of sensitizers, that is, sulfur and trimethylolpropane trimethacrylate (TMPT), on the properties of EBI‐vulcanized natural rubber (NR). The experiments focused on analyzing the effect of different amounts of sensitizers, that is, 2 and 3 phr, on the swelling, crosslink density, entanglement, and mechanical properties of NR latex. A sample without sensitizers was taken as a reference. Results revealed that the crosslink density of the samples with sensitizers had improved compared with that of the sample without a sensitizer. The sample with sulfur exhibited higher crosslink density than the NR with TMPT. The sulfur‐containing NR exhibited superior mechanical properties, i.e., modulus, tensile strength, and tear strength, as its crosslink density increased. In addition, increasing the sulfur content reduced the crosslink density of the NR latex, resulting in inferior mechanical properties. Furthermore, the different forms, that is, latex and film, of NR were compared. The latex form revealed higher crosslink density than the film form, thus presenting high mechanical properties because it contained water, which could induce the formation of free radical species and enhance crosslinking. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescent (TADF) and phosphorescent blue organic light‐emitting diodes (OLEDs) have been developed to overcome the relatively low triplet exciton utilization of traditional fluorescent OLEDs. However, broad emission spectra originating from charge transfer process limits the commercial application of such blue OLEDs. Herein, an effective phosphor‐sensitized fluorescent (PSF) OLED device structure was designed. PSF OLED exhibited a maximum blue index (BI) of 508 cd/A/CIEy with CIEy of 0.060, which has been the highest efficiency result reported for PSF deep‐blue OLEDs. Impressively, the sensitized OLEDs maintained blue index of 407 cd/A/CIEy, narrow emission spectra (FWHM = 17 nm) and high color purity (CIEy = 0.046), revealing the attractive technical advantages and commercial application potential. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescent (TADF) and phosphorescent blue organic light‐emitting diodes (OLEDs) have been developed to overcome the relatively low triplet exciton utilization of traditional fluorescent OLEDs. However, broad emission spectra originating from charge transfer process limit the commercial application of such blue OLEDs. Herein, an effective phosphor‐sensitized fluorescent (PSF) OLED device structure was designed. PSF OLED exhibited a maximum blue index (BI) of 508 cd/A/CIEy with CIEy of 0.060, which has been the highest efficiency result reported for PSF deep‐blue OLEDs. A nearly 100% improvement in operational lifetime LT95 (L/L0 = 95%) was achieved successfully by using lower triplet energy (T1) and deuterated host materials. Impressively, the sensitized OLEDs maintained BI of 407 cd/A/CIEy, narrow emission spectra (FWHM = 17 nm), and high color purity (CIEy = 0.046), revealing the attractive technical advantages and commercial application potential. [ABSTRACT FROM AUTHOR]

A series of CaWO4 ∶Eu3 + ,Bi3 + red phosphors were successfully synthesized by high temperature solid-state reaction. The crystal structure, microstructure, optical property, energy transfer mode, fluorescence lifetime, and thermal stability of samples were characterized by X-ray diffraction, scanning electron microscope and fluorescence spectrophotometer, etc. The results show that when the doping concentrations of Eu3 + and Bi3 + are 7% and 2% (mole fraction), respectively, the red luminescence (615 nm) is the strongest. Theoretical calculations show that the size of this fluorescent powder particle is around 50. 27 nm. This is consistent with the observation results of the electron microscope. The main mode of energy transfer is the interaction between electric dipoles and electric quadrupoles. The fluorescence lifetime of CaWO4∶7%Eu3 + ,xBi3 + (x =0 ~6%) series phosphors were measured, and their fluorescence lifetimes were basically the same, all around 0. 56 ms. By comparing the spectra of CaWO4 ∶7% Eu3 + ,2% Bi3 + phosphors at different temperatures, and the corresponding chromaticity coordinates were calculated. It was found that the overall chromaticity coordinates shift to the left, and the luminescence intensity becomes weaker as the temperature increases, but overall, the thermal stability is good. The good thermal stability and bright red emission indicate that this fluorescent powder can be used as a potential commercial red fluorescent powder. [ABSTRACT FROM AUTHOR]

Cancer remains one of the diseases with the highest incidence and mortality globally. Conventional treatment modalities have demonstrated threatening drawbacks including invasiveness, non-controllability, and development of resistance for some, including chemotherapy, radiation, and surgery. Sono-photodynamic combinatorial therapy (SPDT) has been developed as an alternative treatment modality which offers a non-invasive and controllable therapeutic approach. SPDT combines the mechanism of action of sonodynamic therapy (SDT), which uses ultrasound, and photodynamic therapy (PDT), which uses light, to activate a sensitizer and initiate cancer eradication. The use of phthalocyanines (Pcs) as sensitizers for SPDT is gaining interest owing to their ability to induce intracellular oxidative stress and initiate toxicity under SDT and PDT. This review discusses some of the structural prerequisites of Pcs which may influence their overall SPDT activities in cancer therapy.

Sensitization of wide-gap metal oxides by the porphyrins has been promising to utilize the major fraction of solar light for photocatalytic reactions. In this context, rutile-SnO2 was anchored with hemin complex and their performance was evaluated for the 4-nitro phenol (4-NP) degradation under UV/visible light. Driven by the significant interactions between -COOH and surface -OH functional groups of hemin and SnO2 respectively, a new linkage O=CO-Sn was formed at the interface, which was vital for charge carrier transfer between them. Both X-ray diffraction studies and scanning electron microscope analysis confirmed that the surface hemin adsorption did not alter the crystal structure and the morphology of pristine SnO2. The light absorption properties revealed a red shift in the optical response of the composite, which facilitated the photocatalytic reactions to operate under visible light. The electrochemical and photoluminescence measurements collectively attested to the enhanced charge carrier separation in the composite compared to pure SnO2. The synergism arising from the photo-Fenton and photocatalytic reactions was derived from the cyclic reactions of Fe(II)/Fe(III) and oxidation of hydroxyl radicals by the valence band holes of SnO2 with H2O2 under UV light. In contrast, the sensitization process resulted in electron transfer from the excited state of hemin to the conduction band (CB) of SnO2 under visible light. Such distinct mechanistic pathways by the metal oxide-porphyrin composite would be promising for wastewater purification under UV–visible light region in near future.

The sensitizer is one of the most essential dye-sensitized solar cell (DSSC) components. In the present research, a Znastaxanthin complex was investigated as a sensitizer, compared to pure astaxanthin. The complex with a 1:1 mole ratio between astaxanthin and Zn2+ was synthesized in a reflux reactor at 37-60 °C. The product was analyzed using Proton Nuclear Resonance (1H-NMR), which indicates the presence of chelate formation between Zn2+ with two atoms of oxygen on the terminal cyclohexane ring of astaxanthin. The interaction of sensitizers (astaxanthin and Zn-astaxanthin) on the photoelectrode surface in this study was analyzed using a Fourier Transform Infra-Red (FTIR) and Ultraviolet-Visible Diffuse Reflectance Spectroscopy (UV-Vis DRS). The FTIR spectra of photoelectrode immersed in Zn-astaxanthin show peaks of C=O stretching and vibration -OH group at 1730 and 1273 cm-, respectively, and H-C-H stretching vibration with high intensity in 2939, 2923, and 2853 cm-. The UV-Vis DRS analysis shows the band gap of photoelectrode (PE), photoelectrode immersed in astaxanthin (PE/astaxanthin), and Zn-astaxanthin (PE/Zn-astaxanthin) are 3.19, 1.65, and 1.59 eV, respectively. Under illumination intensity of 300 W/m2, the maximum energy conversion efficiency of DSSC with Zn-astaxanthin as sensitizer is (0.03 + 0.0022)%, higher than DSSC with astaxanthin as sensitizer ((0.12 + 0.0052)%). Up to 70 h of illumination, DSSC with Zn-astaxanthin as a sensitizer also has better stability than astaxanthin-based DSSC. [ABSTRACT FROM AUTHOR]

Cancer remains one of the diseases with the highest incidence and mortality globally. Conventional treatment modalities have demonstrated threatening drawbacks including invasiveness, non-controllability, and development of resistance for some, including chemotherapy, radiation, and surgery. Sono-photodynamic combinatorial therapy (SPDT) has been developed as an alternative treatment modality which offers a non-invasive and controllable therapeutic approach. SPDT combines the mechanism of action of sonodynamic therapy (SDT), which uses ultrasound, and photodynamic therapy (PDT), which uses light, to activate a sensitizer and initiate cancer eradication. The use of phthalocyanines (Pcs) as sensitizers for SPDT is gaining interest owing to their ability to induce intracellular oxidative stress and initiate toxicity under SDT and PDT. This review discusses some of the structural prerequisites of Pcs which may influence their overall SPDT activities in cancer therapy. Discussing the possible roles of phthalocyanines' structural designs on their sono-photodynamic combinatorial therapy activities for enhanced cancer treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) and time dependent DFT (TD‐DFT) techniques are used to explore six donor‐pi‐acceptor (D−A) type sensitizers that comprise coumarin as the donor unit and cyanoacrylic acid as the acceptor unit. It is examined how adding a spacer bridge like 3,4‐ethylenedioxythiophene (EDOT) affects the system. The introduction of EDOT leads to destabilization of highest occupied molecular orbital (HOMO) in both bare and TiO2 anchored sensitizers. The frontier molecular orbital (FMO) also depicts an effective intramolecular charge transfer from the EDOT unit to the acceptor unit in bare sensitizers and to the TiO2 core in TiO2 anchored sensitizers respectively. The FMO diagram of TiO2 anchored non‐bridged sensitizers reveals an electron‐deficient sensitizer unit coupled to an electron‐rich TiO2 core resulting in a poor charge transfer. The calculated Voc values are also found to be more for EDOT based sensitizers and hence making the EDOT bridged sensitizers efficient for DSSC application. According to the TD‐DFT investigation, the EDOT bridging sensitizers exhibit red‐shifted vertical excitation when compared to the corresponding non bridged sensitizers, which is consistent with the experimental data reported previously. [ABSTRACT FROM AUTHOR]

The aim of this work was finding new flurescent dyes as sensitizers for chemiluminescence (CL) determination some of narcotics. In this way 6 different dyes incloding rhodamine 6G, brilliant blue, orange G, chromatrope, eosin‌‌Y and [Ru(phen)3]2+ and 14 drugs incloding pethidine hydrochloride, thebaine, dextromethorphan, acetaminophen, codeine, oxymorphone, oxycodone, morphine, pholcodine, naltrexone, buprenorphine, methadone, tramadol, diphenoxylate were investigated. In the preliminary experiments, we found that pethidine hydrochloride in CL system of [Ru(phen)3]2+- Ce(IV) and thebaine in CL system of rhodamine 6G- Ce(IV) could be determined. After optimizing the important variables, linear dynamic range for pethidine hydrochloride and thebaine were 5.6×10-7 to 1.4×10-3 mol L-1 and 1.0×10-5 to 4.0×10-4 mol L-1 and limit of detection were 7.1×10-8 mol L-1 and 4.3×10-6 mol L-1, respectively. The percent of relative standard deviation for pethidine hydrochloride and thebaine were 5.7 and 4.0%, respectively.

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An increasing number of studies have documented atypical protein kinase C isoform ι (PKCι) as an oncoprotein playing multifaceted roles in pancreatic carcinogenesis, including sustaining the transformed growth, prohibiting apoptosis, strengthening invasiveness, facilitating autophagy, as well as promoting the immunosuppressive tumor microenvironment of pancreatic tumors. In this study, we present novel evidence that PKCι overexpression increases STAT3 phosphorylation at the Y705 residue while decreasing STAT3 phosphorylation at the S727 residue in pancreatic cancer cells. We further demonstrate that STAT3 phosphorylation at Y705 and S727 residues is mutually antagonistic, and that STAT3 Y705 phosphorylation is positively related to the transcriptional activity of STAT3 in pancreatic cancer cells. Furthermore, we discover that PKCι inhibition attenuates STAT3 transcriptional activity via Y705 dephosphorylation, which appears to be resulted from enhanced phosphorylation of S727 in pancreatic cancer cells. Finally, we investigate and prove that by modulating the STAT3 activity, the PKCι inhibitor can synergistically enhance the antitumor effects of pharmacological STAT3 inhibitors or reverse the anti-apoptotic side effects incited by the MEK inhibitor, thereby posing as a prospective sensitizer in the treatment of pancreatic cancer cells. [ABSTRACT FROM AUTHOR]

The determination of phosphorus in rain water is of great significance. In this paper the optimum conditions of phosphorus molybdenum blue spectrophotometric method for the determination of phosphorus content were obtained. At the maximum absorption wavelength 690 nm, the apparent molar absorptivity is e690 nm = 1.44 × 104 L·mol-1·cm-1. Beer's law is followed over the range of 0.02-1.8 µg·mL-1 for phosphorus(V) content. Bismuth(III) and antimony(III) as the sensitizer has a sensitization effect on the phosphomolybdenum blue photometry. The addition of both simultaneously increases the sensitivity by 71.3%. The present method has been used for the determination of phosphorus in water samples. The recovery of method is between 99.20 - 100.1% and the relative standard deviation is between 1.31-1.33% for eleven determination. The results determined by the present method were in agreement with those of atomic absorption spectrometry. This method can avoid the harm of organic reagent to human body and to environmental pollution without organic solvent extraction. This method does not need heating with room temperature color development. Compared with other methods, it has the advantages that the operation is simple, fast and the sensitivity is high. [ABSTRACT FROM AUTHOR]

Two newly designed and synthesized [3+2+1] iridium complexes through introducing bulky trimethylsiliyl (TMS) groups are doped with a terminal emitter of v-DABNA to form an coincident overlapping spectra between the emission of these two phosphors and the absorption of v-DABNA, creating cascade resonant energy transfer for efficient triplet harvesting. To boost the color quality and efficiency, the fabricated hyper-OLEDs have been optimized to achieve a high external quantum efficiency of 31.06%, which has been among the highest efficiency results reported for phosphor sensitized saturated-blue hyper-OLEDs, and pure blue emission peak at 467 nm with the full width at half maxima (FWHM) as narrow as 18 nm and the CIE[sub y] values down to 0.097, satisfying the National Institute of Standards and Technology (NIST) requirement for saturated blue OLEDs display. Surprisingly, such hyper-OLEDs have obtained the converted lifetime (LT50) up to 4552 h at the brightness of 100 cd m-2, demonstrating effective Förster resonance energy transfer (FRET) process. Therefore, employing these new bulky TMS substituent [3+2+1] iridium(III) complexes for effective sensitizers can greatly pave the way for further development of high efficiency and stable blue OLEDs in display and lighting applications. [ABSTRACT FROM AUTHOR]

Combining phytochemicals with chemotherapeutic drugs has demonstrated the potential to surmount drug resistance. In this paper, we explore the efficacy of pentagalloyl glucose (PGG) in modulating P-gp and reversing multidrug resistance (MDR) in drug-resistant leukemic cells (K562/ADR). The cytotoxicity of PGG was evaluated using a CCK-8 assay, and cell apoptosis was assessed using flow cytometry. Western blotting was used to analyze protein expression levels. P-glycoprotein (P-gp) activity was evaluated by monitoring the kinetics of P-gp-mediated efflux of pirarubicin (THP). Finally, molecular docking, molecular dynamics simulation, and molecular mechanics with generalized Born and surface area solvation (MM-GBSA) calculation were conducted to investigate drug–protein interactions. We found that PGG selectively induced cytotoxicity in K562/ADR cells and enhanced sensitivity to doxorubicin (DOX), indicating its potential as a reversal agent. PGG reduced the expression of P-gp and its gene transcript levels. Additionally, PGG inhibited P-gp-mediated efflux and increased intracellular drug accumulation in drug-resistant cells. Molecular dynamics simulations and MM-GBSA calculation provided insights into the binding affinity of PGG to P-gp, suggesting that PGG binds tightly to both the substrate and the ATP binding sites of P-gp. These findings support the potential of PGG to target P-gp, reverse drug resistance, and enhance the efficacy of anticancer therapies. [ABSTRACT FROM AUTHOR]

Metal‐organic framework (MOF)‐sensitized solar cells (MSSC) were fabricated using aniline‐doped MOF‐199. The light harvesting and semiconductor properties of MOF‐199 were fine‐tuned by introducing aniline as guest molecules. After doping with aniline structural changes were not depicted in the powder X‐ray diffraction pattern confirming the undisturbed 3D framework of MOF‐199. A clear color change was observed after doping due to which enhanced absorbance peaks were observed in the UV‐visible spectra. The modified MOF‐199 was then utilized in MOF‐sensitized solar cells as the light‐absorbing material that demonstrated a 73 % enhancement in the overall device efficiency when compared to MSSC fabricated with unmodified/neat MOF‐199. [ABSTRACT FROM AUTHOR]

Organic lanthanide complexes have garnered significant attention in various fields due to their intriguing energy transfer mechanism, enabling the upconversion (UC) of two or more low-energy photons into high-energy photons. In comparison to lanthanide-doped inorganic nanoparticles, organic UC complexes hold great promise for biological delivery applications due to their advantageous properties of controllable size and composition. This review aims to provide a summary of the fundamental concept and recent developments of organic lanthanide-based UC materials based on different mechanisms. Furthermore, we also detail recent applications in the fields of bioimaging and solar cells. The developments and forthcoming challenges in organic lanthanide-based UC offer readers valuable insights and opportunities to engage in further research endeavors. [ABSTRACT FROM AUTHOR]

Background: Hair dye is a concoction of various ingredients that can result in allergic contact dermatitis (ACD) which is a common problem encountered by dermatologists. Objectives: To find out the presence of potent contact sensitizers in commercially available hair dyes in Puducherry, a union territory in South India, and to compare the findings with similar studies conducted in different countries. Methods: Ingredients labels of 159 hair dye products from 30 brands that were manufactured and marketed in India screened for the presence of contact sensitizers. Results: A total of 25 potent contact sensitizers were found in 159 hair dye products. p‐Phenylenediamine and resorcinol were the most frequent contact sensitizer found in the study. The mean contact sensitizer concentration in a single hair dye product is 3.72 ± 1.81. The number of potent contact sensitizers in individual hair dye products ranged from 1 to 10. Conclusion: We observed that most of the consumer‐available hair dyes contain multiple contact sensitizers. Also, an inadequacy in mentioning the p‐Phenylenediamine content, and appropriate warning contents regarding hair dye use were not mentioned in the cartons. [ABSTRACT FROM AUTHOR]

Nanostructured oxides (SiO2, TiO2) were synthesized using the sol–gel method and modified with noble metal nanoparticles (Pt, Au) and ruthenium dye to enhance light harvesting and promote the photogeneration of reactive oxygen species, namely singlet oxygen (1O2) and hydroxyl radical (•OH). The resulting nanostructures were embedded in a transparent polyvinyl alcohol (PVA) hydrogel. Morphological and structural characterization of the bare and modified oxides was performed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), UV–Vis spectroscopy, and X-ray photoelectron spectroscopy (XPS). Additionally, electrokinetic potential measurements were conducted. Crystallinity data and elemental analysis of the investigated systems were obtained through X-ray diffraction and X-ray fluorescence analyses, while the chemical state of the elements was determined using XPS. The engineered materials, both as simple powders and embedded in the hydrogel, were evaluated for their ability to generate reactive oxygen species (ROS) under visible and simulated solar light irradiation to establish a correlation with their antibacterial activity against Staphylococcus aureus. The generation of singlet oxygen (1O2) by the samples under visible light exposure can be of significant importance for their potential use in biomedical applications. [ABSTRACT FROM AUTHOR]

Intensity of the bands of upconversion luminescence of β-NaYF4:Yb3+/Tm3+ nanopowders in DMSO suspensions vs intensity of exciting radiation were analyzed. Ranges of changes in the intensity of excitation have been established, in which either the processes of energy transfer from the sensitizer ion to the activator ion or the decay of intermediate levels of activator ions dominate. [ABSTRACT FROM AUTHOR]

This paper aims at preparing UV-curable coatings for hot-dip aluminum-zinc coated steel plates.Using trimethylolpropane triacrylate (TMPTA) and 2-phenoxyethyl acrylate as active diluents,the mixture of modified epoxy acrylate and modified polyester acrylate in a certain proportion as the oligomer,2-methyl-1-[4-(methylthio)benzene]-2-morpholinacetone (907) as the free radical photoinitiator,and isopropyl thioxanthone (ITX) as the sensitizer,the free radical light curing agent formula was compounded using high pressure mercury lamp as radiation source.The as-obtained light curing agent was coated on the surface of hot-dip aluminum-zinc coated steel plate.After curing treatment,the passivation film was characterized by neutral salt spray testing,electrochemical testing and other means.Results showed that the passivation films of this system could be cured at an energy of 600 mJ/cm2,and their general performance and resistance to neutral salt spray test (NSST) were able to meet the basic requirements of downstream users of hot-dip aluminum-zinc coated steel plate.

Triplet‐triplet annihilation upconversion (TTA‐UC) with near‐infrared (NIR) photosensitizers is highly desirable for a variety of emerging applications. However, the development of NIR‐to‐blue TTA‐UC with a large anti‐Stokes shift is extremely challenging because of the energy loss during the intersystem crossing (ISC). Here, we develop the first NIR‐absorbing B,N‐heteroarene‐based sensitizer (BNS) with multi‐resonance thermally activated delayed fluorescence (MR‐TADF) characters to achieve efficient NIR‐to‐blue TTA‐UC. The small energy gap between the singlet and triplet excited states (0.14 eV) of BNS suppresses the ISC energy loss, and its long‐delayed fluorescence lifetime (115 μs) contributes to efficient triplet energy transfer. As a result, the largest anti‐Stokes shift (1.03 eV) among all heavy‐atom‐free NIR‐activatable TTA‐UC systems is obtained with a high TTA‐UC quantum yield of 2.9 % (upper limit 50 %). [ABSTRACT FROM AUTHOR]

[Display omitted] Luminescence thermometry using sharp line emission of lanthanide ions has become an active area of research as it offers the advantages of remote temperature sensing with high sensitivity and superior spatial resolution. The most widely applied method relies on the temperature dependence of the luminescence intensity ratio of emission lines from two thermally coupled levels. However, the usable temperature range for this type of Boltzmann thermometer is limited. In addition, the weak and narrow line absorption of the parity forbidden 4f-4f transitions of lanthanides forms a serious drawback. To solve both problems, we here report a new dual functionality luminescence thermometer: Gd 2 O 2 S co-doped with Eu3+ and Nd3+. This material combines Boltzmann and energy transfer thermometry to extend the temperature range and uses the strong and broad charge transfer absorption band of Eu3+ for sensitization. In the T -range of 300–500 K efficient energy transfer from Eu3+ to Nd3+ allows for charge transfer-sensitized luminescence thermometry using near infrared emission from the thermally coupled 4F 3/2 and 4F 5/2 levels of Nd3+. Above 500 K a high temperature sensitivity is obtained using the strong temperature dependence of the luminescence intensity ratio of red Eu3+ to near infrared Nd3+ emission. The dual-functionality provides a single thermometer combining strong absorption and high relative sensitivity (0.6 – 1.4%) over a wide temperature range (300 to 650 K). Finally, it is proposed that this dual-function luminescent thermometer has promising potential for multifunctional applications in biosensors and in situ temperature measurements of chemical reaction process. [ABSTRACT FROM AUTHOR]

BODIPY heterochromophores, asymmetrically substituted with perylene and/or iodine at the 2 and 6 positions were prepared and investigated as sensitizers for triplet‐triplet annihilation up conversion (TTA‐UC). Single‐crystal X‐ray crystallographic analyses show that the torsion angle between BODIPY and perylene units lie between 73.54 and 74.51, though they are not orthogonal. Both compounds show intense, charge transfer absorption and emission profiles, confirmed by resonance Raman spectroscopy and consistent with DFT calculations. The emission quantum yield was solvent dependent but the emission profile remained characteristic of CT transition across all solvents explored. Both BODIPY derivatives were found to be effective sensitizers of TTA‐UC with perylene annihilator in dioxane and DMSO. Intense anti‐Stokes emission was observed, and visible by eye from these solvents. Conversely, no TTA‐UC was observed from the other solvents explored, including from non‐polar solvents such as toluene and hexane that yielded brightest fluorescence from the BODIPY derivatives. In dioxane, the power density plots obtained were strongly consistent with TTA‐UC and the power density threshold, the Ith value (the photon flux at which 50 % of ΦTTAUC is achieved), for B2PI was observed to be 2.5x lower than of B2P under optimal conditions, an effect ascribed to the combined influence of spin‐orbit charge transfer intersystem crossing (SOCT‐ISC) and heavy metal on the triplet state formation for B2PI. [ABSTRACT FROM AUTHOR]

Context: Comparatively, metal-free sensitizers featuring the chalcogen family receive less attention despite known electronic properties for metal-chalcogenide materials. This work reports an array of optoelectronic properties using quantum chemical methods. Observed red-shifted bands within the UV/Vis to NIR regions with absorption maxima > 500 nm were consistent with increasing chalcogenide size. There is a monotonic down-shift in the LUMO and ESOP energy consistent with O 2p, S 3p, Se 4p, to Te 5p atomic orbital energies. Excited-state lifetime and charge injection free energies follow the decreasing order of chalcogenide electronegativity. Adsorption energies of dyes on TiO2 anatase (101) range between − 0.08 and − 0.77 eV. Based on evaluated properties, selenium- and tellurium-based materials show potential use in DSSCs and futuristic device applications. Therefore, this work motivates continued investigation of the chalcogenide sensitizers and their application. Methods: The geometry optimization was performed at B3LYP/6–31 + G(d,p) and B3LYP/LANL2DZ level of theory for lighter and heavier atoms, respectively, using Gaussian 09. The equilibrium geometries were confirmed by the absence of imaginary frequencies. Electronic spectra were obtained at CAM-B3LYP/6-31G + (d,p)/LANL2DZ level of theory. Adsorption energies for dyes on a 4 × 5 supercell TiO2 anatase (101) were obtained using VASP. The dye-TiO2 optimizations were employed using GGA and PBE with the PAW pseudo-potentials. The energy cutoff was set at 400 eV and convergence threshold for self-consistent iteration was set to 10−4, and van der Waals were accounted using DFT-D3 model and on-site Coulomb repulsion potential set at 8.5 eV for Ti. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sensitized photooxidation of Tyr yields formation of three types of products: di-Tyr, Tyr-CBH adducts and Tyr-2 Da. • Blocking of amine or carboxylic group induce formation of more isomers of di-Tyr, while the Tyr-CBH is not visible. • N-Ac-Tyr-OEt derivative with both groups blocked showed the formation of ten different isomers of di-Tyr. One-electron oxidation of tyrosine primarily results in the formation of di-tyrosine, which can induce crosslinks leading to protein damage. In this study, we investigated the 3-carboxybenzophenone-sensitized photo-oxidation of Tyr derivatives through time-resolved and steady-state photolysis under anaerobic conditions to analyze the effects of blocking groups. The mechanism for primary and secondary photoreactions in the sensitized photo-oxidation of Tyr derivatives in aqueous solution was presented based on time-resolved analysis and mass spectrometric characterization of photo-oxidation products. Identified di-Tyr products (in addition to those mentioned more often in the literature, such as 3,3′/3,O') were in some samples presented together with Tyr-CBH adduct (resulting from radical recombination between the tyrosyl radical and CBH•). This publication discusses the possible coulombic effects of interacting ionic species (sensitizer and quencher) on quenching rate constants and the effect of amine groups and steric factors on the distribution of stable products. However, a crucial finding of this work is that the more blocked the Tyr is, the more di-Tyr isomers are formed, suggesting that Tyr residue in proteins may form several forms of di-Tyr cross-links. [ABSTRACT FROM AUTHOR]