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This study introduces a new in-syringe homogeneous liquid-phase microextraction method for the rapid on-site extraction of chloroanilines from water samples. Extraction was performed using a plastic syringe, eliminating the use of any electrical power source. Di-(2-ethylhexyl) phosphoric acid (DEHPA) served as the extractant. The process initially involved dissolving DEHPA in an alkaline solution to obtain a homogeneous solution. Subsequently, the sodium salt of DEHPA was precipitated by salting-out, and the resulting heterogeneous mixture was filtered using a syringe filter. The precipitate containing the analytes was then dissolved in methanol for analysis by high-performance liquid chromatography. Under optimal conditions, extraction recovery for chloroanilines ranged from 26% to 71%. Method linearity was evaluated within a concentration range of 1.0-100 µg/L, resulting in coefficients of determination exceeding 0.9987 for all analytes. Method detection limits ranged from 0.28 to 0.41 µg/L. Intra and inter-day precision values were below 9.5% and 10.8%, respectively. The developed method was applied to determine chloroanilines in real waters, yielding acceptable recoveries ranging from 80% to 109% for spiked tap, rain, and stream waters. Additionally, the method was successfully employed for on-site extraction of target contaminants, demonstrating no statistically significant differences compared to laboratory results.
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Borondipyrromethene (BODIPY) chromophores are composed of a functional-COOH group at meso position with or without a biphenyl ring, and their compounds with heavy iodine atoms at -2, -6â positions of the BODIPY indacene core were synthesized. The photophysical properties of the compounds were studied with steady-state absorption and fluorescence measurements. It was observed that the absorption band is significantly red-shifted, and fluorescence signals are quenched in the presence of iodine atoms. In addition to that, it was indicated that the biphenyl ring does not affect the spectral shifting in the absorption as well as fluorescence spectra. In an attempt to investigate the effect of π-expanded biphenyl moieties and heavy iodine atoms on charge transfer dynamics, femtosecond transient absorption spectroscopy measurements were carried out in the environment of the tetrahydrofuran (THF) solution. Based on the performed ultrafast pump-probe spectroscopy, BODIPY compounds with iodine atoms lead to intersystem crossing (ISC) and ISC rates were determined as 150â ps and 180â ps for iodine BODIPY compounds with and without π-expanded biphenyl moieties, respectively. According to the theoretical results, the charge transfer in the investigated compounds mostly appears to be intrinsic local excitations, corresponding to high photoluminescence efficiency. These experimental findings are useful for the design and study of the fundamental photochemistry of organic triplet photosensitizers.
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PURPOSE: The aim of this study was to evaluate the effect of compression bandage applied with different pressures on the skin and subcutaneous thickness in individuals with breast cancer-related lymphedema (BCRL). METHODS: 21 individuals with stage 2 unilateral BCRL participated in the study. Individuals were randomly allocated into two groups as low-pressure bandage (20-30 mmHg) (n: 11) and high-pressure bandage (45-55 mmHg) (n: 10). Skin and subcutaneous tissue thickness, extremity volume, sleep quality, treatment benefit, and comfort were evaluated by ultrasound from 6 reference points (as hand dorsum, wrist volar, forearm volar, arm volar, forearm dorsum, and arm dorsum), volumetric measurement, Pittsburgh Sleep Quality Index, Patient Benefit Index-Lymphedema, and visual analog scale, respectively. Complex decongestive physiotherapy was applied to both groups. Compression bandage was applied according to their group. Individuals were evaluated at the baseline, 1st session, 10th session, 20th session, and at 3-month follow-up. RESULTS: Skin thickness decreased significantly in the volar reference points of the extremity in the high-pressure bandage group (p = 0.004, p = 0.031, and p = 0.003). Subcutaneous tissue thickness significantly decreased at all reference points in the high-pressure bandage group (p < 0.05). In the low-pressure bandage group, skin thickness only decreased in the forearm dorsum and the arm dorsum (p = 0.002, p = 0.035) and subcutaneous tissue thickness changed for all points (p < 0.05) except for hand and arm dorsum (p = 0.064, p = 0.236). Edema decreased in a shorter time in the high-pressure bandage group (p < 0.001). No significant differences were found in sleep quality, treatment benefit, and comfort for both groups (p = 0.316, p = 0.300, and p = 0.557, respectively). CONCLUSION: High pressure was more effective in reducing subcutaneous tissue thickness in the dorsum of hand and arm. The usage of high-pressure can be recommended especially in cases which have edema in the dorsum of hand and arm which is difficult to resolve. Also, high-pressure bandage can provide faster edema resolution and can be used in rapid volume reduction as desired. Treatment outcomes may improve with high-pressure bandage without any impairment in comfort, sleep quality, and treatment benefit. TRIAL REGISTRATION NUMBER AND DATE: NCT05660590, 12/26/2022 retrospectively registered.
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Linfedema Relacionado a Câncer de Mama , Neoplasias da Mama , Linfedema , Humanos , Feminino , Tela Subcutânea , Neoplasias da Mama/complicações , Neoplasias da Mama/terapia , Linfedema Relacionado a Câncer de Mama/terapia , Modalidades de Fisioterapia , Linfedema/terapia , Bandagens Compressivas , Edema , Resultado do TratamentoRESUMO
INTRODUCTION AND HYPOTHESIS: Pelvic organ prolapse (POP) is a common morbidity and 10-20% of the patients need surgical correction. Sacrocolpopexy or sacrohysteropexy procedures are satisfactory but still difficult. Lateral suspension (LS) as a safe and simple technique has become an alternative technique recently. Vaginal natural orifice transluminal endoscopic surgery (V-NOTES) is also a new modality and LS using V-NOTES has not been performed previously and should be promising. METHODS: This prospective observational pilot study was conducted with a total of 38 women with stage 3 and 4 POP according to the Pelvic Organ Prolapse Quantification grading system (POP-Q). Lateral suspension via V-NOTES was performed with the Salman-Ketenci Gencer technique using a mesh for POP. The preoperative and postoperative 6-month POP-Q stages together with Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12) scores were recorded and compared. RESULTS: Comparison of the preoperative and postoperative 6-month POP-Q stages of the patients were statistically significant except for the total vaginal length (p<0.01). Compared with the preoperative total and subscale scores of PISQ-12, the postoperative values were considerably improved (p<0.001). CONCLUSIONS: With the Salman-Ketenci Gencer technique not only good anatomical but also good functional results were obtained with V-NOTES. Surgeons may focus on uterine sparing while using the Salman-Ketenci Gencer technique for apical prolapse owing to the higher rate of complications related to the colposuspension and better sexual results after the cervicosuspension.
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Prolapso de Órgão Pélvico , Vagina , Feminino , Humanos , Resultado do Tratamento , Estudos Prospectivos , Vagina/cirurgia , Prolapso de Órgão Pélvico/cirurgia , Útero/cirurgia , Inquéritos e Questionários , Telas Cirúrgicas , Procedimentos Cirúrgicos em Ginecologia/métodosRESUMO
AIM: To determine whether there was a significant difference between serum endocan levels of pregnant women with and without gestational diabetes mellitus (GDM). METHODS: A total of 90 pregnant women, 45 with gestational diabetes and 45 healthy pregnant women, between 24 and 28 gestational weeks, were included in this prospective case-control study. The pregnant women were screened for gestational diabetes using a two-step protocol. Serum endocan levels were measured using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. A p-value of <0.05 was considered statistically significant. RESULTS: Serum endocan level was significantly higher in the GDM group than in healthy controls (168.46 ± 160.6 vs. 105.66 ± 26.52 pg/mL, respectively; p < 0.001). Serum endocan concentrations were positively correlated with the results of 50 g oral glucose challenge test (GCT) (p < 0.001). Receiver operating characteristic curve analysis showed that endocan with a cut-off point of 133.9 ng/dL indicated women with GDM with a sensitivity of 55.6% and specificity of 88.9% (area under the curve [AUC]: 0.737, 95% CI: 0.634-0.824). The overall differential performance of endocan according to the GDM groups was determined as 73.7% (p < 0.001). Maternal serum endocan level was positively correlated with fasting glucose, postprandial glucose, and glycated hemoglobin (HbA1c) (p < 0.001). CONCLUSIONS: Elevated endocan levels in gestational diabetes were correlated with fasting glucose, postprandial glucose, HbA1c, and oral glucose tolerance test (OGTT) results. Despite the low sensitivity of 55.6% and the high specificity of 88.9%, we found a high differential performance rate indicating that serum endocan levels were important for the pathophysiology of GDM and should be investigated for the possibility of being a novel marker in larger populations.
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Diabetes Gestacional , Feminino , Humanos , Gravidez , Glicemia/análise , Estudos de Casos e Controles , Diabetes Gestacional/diagnóstico , Glucose , Teste de Tolerância a Glucose , Hemoglobinas GlicadasRESUMO
BACKGROUND: There are limited studies focusing on hemodynamic changes between elective and emergent C/S cases. We considered that a better understanding of the alterations and physiological reactions in both situations with non-invasive novel technologies might be useful in managing maternal and fetal sides. METHODS: In this prospective observational study, non-invasive hemodynamic changes were observed by using the whole-body impedance method using the NICaS™ device. CO, cardiac index (CI), stroke volume (SV), stroke index (SI), total peripheric resistance (TPR), and cardiac reserve (GGI) parameters were evaluated with a non-invasive method. Measurements were done initiating before surgery, 9 times of 5 min intervals. RESULTS: All 95 patients finished the study. 47 cesarean sections were in the elective group, 48 were in the emergent group. SV in 4.5.6. time intervals were statistically increased in the elective group (p values: SvMl4: 0.025, SvMl5: 0.049, SvMl6: 0.044) (p < 0.05). SI in the second-time interval was statistically increased in the emergent group (p-value SI2: 0.047) (p < 0.05). SI in the 4th time interval was statistically increased in the elective group (p-value SI4: 0.047) (p < 0.05). CO measurements were not statistically different between groups in all time intervals for all comparisons. CI in the second time interval was statistically decreased in the elective group (p-value CI2: 0.012) (p < 0.05). GGI in the 4th time interval was statistically increased in the elective group (p-value GGI4: 0.035) (p < 0.05). TPRI in the second time interval was statistically increased in the elective group (p-value TPRI 2: 0.014) (p < 0.05). CONCLUSIONS: Understanding normal hemodynamic values before, during, and after C/S is feasible and might help the clinician assess patients' cardiac performance with a reliable noninvasive technique. NICaS might be a reliable tool to evaluate patients' baseline values and diagnose complications earlier during the surgery.
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Background/aim: To evaluate whether there is a relationship between serum myosin-binding protein C (MyBP-C) levels measured in the first trimester and the timing of delivery, and, if a relationship is detected, the potential of this relationship in distinguishing between preterm and term labor. Materials and methods: This prospective case-control study was conducted with 701 pregnant women who applied to the Obstetrics Outpatient Clinic of Gaziosmanpasa Training and Research Hospital in the first trimester, between 11 and 14 gestational weeks. MyBP-C serum samples from the first trimester were stored under appropriate conditions until the time of delivery. Of these pregnant women, 628 completed the study. According to the delivery time, the pregnant women were divided into two groups, as those who delivered prematurely before 37 weeks and those who gave birth at term. The case group comprised 45 women who gave birth prematurely, while 583 women gave birth at term. A control group was formed with 45 pregnant women of the same age, who were selected by randomization using a simple random sampling method from the 583 pregnant women. The MyBP-C levels were measured and compared from the first-trimester serum materials of both groups. Results: The MyBP-C levels of the preterm delivery group were significantly higher than those of the term delivery control group (4.51 ± 1.69 vs. 3.09 ± 1.44 pg/mL, respectively; p < 0.001). Receiver operating characteristic (ROC) curve analysis showed that the MyBP-C levels in the first trimester with a cut-off value of 4.76 ng/dL indicated women with preterm delivery with a sensitivity of 42.22% and specificity of 95.56% (AUC: 0.734, 95% CI: 0.630-0.822). The overall differential diagnosis performance of the MyBP-C level for preterm delivery was determined as 73.4% (p < 0.001). The MyBP-C levels were found to be significantly higher both in the early preterm group compared with the late preterm group (p < 0.001), and in those with premature rupture of membranes (PROM) compared with those without (p < 0.001). Conclusion: The preterm delivery group exhibited high serum MyBP-C levels in the serum samples taken in the first trimester. First-trimester serum MyBP-C levels seem to be a simple and easy way to exclude preterm delivery risk in a significant manner. In addition, levels are significantly higher for early preterm compared with late preterm and early PROM compared with intact membranes.
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Biomarcadores , Proteínas de Transporte , Primeiro Trimestre da Gravidez , Nascimento Prematuro , Humanos , Feminino , Gravidez , Nascimento Prematuro/sangue , Estudos Prospectivos , Biomarcadores/sangue , Adulto , Estudos de Casos e Controles , Proteínas de Transporte/sangue , Primeiro Trimestre da Gravidez/sangue , Curva ROCRESUMO
Aza-BODIPY compounds with methoxy groups at -3 and -5 and triphenylamine moieties at -1 and -7 positions with and without heavy bromine atoms at -2 and -6 positions have been designed and synthesized. The chemical structures of the novel compounds were fully characterized using 1H NMR, 13C NMR, FTIR, and HRMS-TOF-ESI techniques. Steady-state absorption and emission features were investigated to analyze ground-state interactions. The effects of triphenylamine moieties and bromine atoms on charge transfer dynamics and two-photon absorption (TPA) properties were investigated using femtosecond transient absorption spectroscopy measurements and open-aperture (OA) Z-scan experiments, respectively. Contrary to popular belief, the compound containing heavy bromine atoms and triphenylamine moieties did not demonstrate any triplet transition. Since the triphenylamine moiety has high electron-donating properties and a long conjugation length, it exhibited intramolecular charge transfer (ICT) features from electron-donating moieties to the aza-BODIPY core. Additionally, it is concluded that the excited-state lifetime is shortened in the presence of a bromine atom with triphenylamine moieties. This result is rather interesting since the triplet excited state is quenched by the triphenylamine moiety despite the presence of a heavy bromine atom. The performed OA Z-scan experiments revealed that the aza-BODIPY compound containing bromine atoms has a higher TPA cross-section value (116 GM) due to efficient intramolecular charge transfer compared to that without bromine atoms (89 GM). Additionally, in the theoretical calculations, it was found that the charge transfer percentage (CT%) was the strongest in compounds containing bromine atoms.
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Compostos Aza , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/química , Bromo , Teoria Quântica , Compostos de Boro/química , Compostos Aza/químicaRESUMO
The replacement of traditional ruthenium-based photosensitizers with low-cost and abundant iron analogs is a key step for the advancement of scalable and sustainable dye-sensitized water splitting cells. In this proof-of-concept study, a pyridinium ligand coordinated pentacyanoferrate(II) chromophore is used to construct a cyanide-based CoFe extended bulk framework, in which the iron photosensitizer units are connected to cobalt water oxidation catalytic sites through cyanide linkers. The iron-sensitized photoanode exhibits exceptional stability for at least 5â h at pHâ 7 and features its photosensitizing ability with an incident photon-to-current conversion capacity up to 500â nm with nanosecond scale excited state lifetime. Ultrafast transient absorption and computational studies reveal that iron and cobalt sites mutually support each other for charge separation via short bridging cyanide groups and for injection to the semiconductor in our proof-of-concept photoelectrochemical device. The reorganization of the excited states due to the mixing of electronic states of metal-based orbitals subsequently tailor the electron transfer cascade during the photoelectrochemical process. This breakthrough in chromophore-catalyst assemblies will spark interest in dye-sensitization with robust bulk systems for photoconversion applications.
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Ferro , Água , Ferrocianetos , OxirreduçãoRESUMO
Invited for the cover of this issue is the Ferdi Karadas and Ekmel Ozbay groups at Bilkent University and co-workers. The image presents an utopic city in Iron Age, which is powered by an iron photosensitizer that bridges semiconductor buildings (TiO2 nanowires) and the catalyst (cobalt site). Read the full text of the article at 10.1002/chem.202100654.
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Ferro , Água , Catálise , Ferrocianetos , HumanosRESUMO
A 4-amino-2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) radical was attached to the bay position of perylene-3,4 : 9,10-bis(dicarboximide) (perylenebisimide, PBI) to study the radical-enhanced intersystem crossing (REISC) and electron spin dynamics of the photo-induced high-spin states. The dyads give strong visible light absorption (ϵ=27000â M-1 cm-1 at 607â nm). Attaching a TEMPO radical to the PBI unit transforms the otherwise non-radiative decay of S1 state (fluorescence quantum yield: ΦF =2.9 %) of PBI unit to ISC (singlet oxygen quantum yield: ΦΔ =31.8 %, ΦF =1.6 %). Moreover, the REISC is more efficient as compared to the heavy atom effect-induced ISC (ΦΔ =17.8 % for 1,8-dibromoPBI). For the dyad, ISC takes 245â ps and triplet state lifetime is 1.5 µs, much shorter than the native PBI (τT =126.6 µs). X- and Q-band time-resolved electron paramagnetic resonance spectroscopy shows that the exchange interaction in the photoexcited radical-chromophore dyad is larger than the triplet zero-field splitting (ZFS) and the difference of Zeeman energies of the radical and chromophore. The inversion of electron spin polarization from emissive to absorptive was observed and attributed to the initial completion of the quartet state population and the subsequent depopulation processes induced by the zero-field splitting.
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In this study, a sensitive analytical method was developed to determine some pesticides (cyprodinil, trifloxystrobin, prometryn, propachlor, fenitrothion, chlorpyrifos, profenofos, and phosalone) in molasses samples. Pesticides were extracted from samples by dispersive liquid-liquid microextraction method combined with sugaring-out homogeneous liquid-liquid extraction and determined by gas chromatography-mass spectrometry analysis. In this method, pesticides in molasses samples were first extracted using a water-miscible solvent (acetonitrile) in the sugaring-out homogeneous liquid-liquid extraction stage. The sugar in the ratio of 84-88% naturally contained in the molasses sample enabled phase separation in the acetonitrile-water homogeneous mixture. Then acetonitrile phase containing pesticides was used as dispersing solvent in the second step of the process. Under the specified optimum conditions, the limit of detection was calculated between 0.8-6.1 ng/g and the limit of quantification was in the range of 2.5-20 ng/g. The relative standard deviation values of molasses samples containing 150 ng/g of each analyte were found to be lower than 4.9% intra-day and 5.6% for inter-day. This validated method has been successfully applied to different types of molasses.
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ABSTRACT: The gluten-free cookies were produced by replacing rice flour (RF) and sucrose content with almond flour (AF) and stevia. Supplementation of AF caused to decrease the moisture content of the gluten-free cookies; while ash, total protein, total fat and total dietary fiber content increased. Regarding of total phenolics; extractable, hydrolyzable and bioaccessible fractions of gluten-free cookie samples that were produced with 30% of AF supplementation, were increased by 43.69-73% compared with the control group that was prepared with 100% RF (p ≤ 0.01). Gluten was detected in the cookies with neither RF nor AF. No cross-contamination was detected during the production, too. Quality characteristics of the gluten-free cookies reached the acceptable level while AF and stevia contents were increased. Protein and dietary fiber contents of the cookie with AF and stevia were enriched to 82 and 96%, while the total carbohydrate amount decreased 19% (p ≤ 0.01). The contents of TEACABTS and TEACFRAP of gluten-free cookies with AF and stevia were 5.72 ± 0.07 and 26.08 ± 0.49 µmol Trolox/g and higher than the control (100% RF + sucrose). It has found that physicochemical, nutrition and sensorial properties of gluten-free cookies that were produced with AF + stevia supplementation provided to produce more acceptable products.
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Five different tea varieties (white, green, oolong, black and pu-erh) were infused, drained and used for kombucha production. Antioxidant capacity, total phenolic content and bioaccessibility values were determined. Extractable, hydrolysable and bioaccessible fractions were used for antioxidant capacity and total phenolic content (TPC) and expressed as µmole TEAC/mL and mg GAE/100 mL, respectively. Antioxidant capacity and TPC were determined by Folin Ciocalteu's, ABTS and CUPRAC methods. In vitro digestion enzymatic extraction was used to determine bioaccessible fractions. It has found that kombucha fermentation with the tea extracts caused to elevate antioxidant capacity, TPC, and bioaccessibility. The green tea kombucha had the highest antioxidant capacity (4153.23 µmole TEAC/mL) and bioaccessibility (50.18%). Therefore, it can be suggested as a good supplement with high nutritional value in kombucha production. In general, TPC content increased significantly. The extractable fractions and bioaccessibility values of the kombucha tea varieties increased due to the fermentation, while the hydrolysable fractions decreased. Antioxidant capacity in the extractable fractions of the green tea kombucha samples was measured to increase by ABTS and CUPRAC methods. Bioaccessibility values of pu-erh tea by ABTS and white tea by CUPRAC were found to increase by the kombucha production.
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Intersystem crossing (ISC) was observed for naphthalimide (NI)-derived Tröger's base, and the ISC was confirmed to occur by a spin-orbital charge-transfer (SOCT) mechanism. Conventional electron donor/acceptor dyads showing SOCT-ISC have semirigid linkers. In contrast, the linker between the two chromophores in Tröger's base is rigid and torsion is completely inhibited, which is beneficial for efficient SOCT-ISC. Femtosecond transient absorption (TA) spectra demonstrated charge-separation and charge-recombination-induced ISC processes. Nanosecond TA spectroscopy confirmed the ISC, and the triplet state is long-lived (46â µs, room temperature). The ISC quantum yield is dependent on solvent polarity (8-41 %). The triplet state was studied by pulsed-laser-excited time-resolved EPR spectroscopy, and both the NI-localized triplet state and triplet charge-transfer state were observed, which is in good agreement with the spin-density analysis. The Tröger's base was confirmed to be a potent photodynamic therapy reagent with HeLa cells (EC50 =5.0â nm).
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1-Naftilamina/análogos & derivados , Naftalimidas/química , Fotoquimioterapia , Quinolonas/química , Solventes/química , 1-Naftilamina/química , Espectroscopia de Ressonância de Spin Eletrônica , Células HeLa , HumanosRESUMO
Two anthryl platinum(II) N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-benzenediamine Schiff base complexes were synthesized, with the anthryl attached via its 9 position (Pt-9An) or 2 position (Pt-2An) to the platinum (Pt) Schiff base backbone. The complexes show unusually small Stokes shifts (0.23 eV), representing a very small energy loss for the photoexcitation/intersystem crossing process, which is beneficial for applications as triplet photosensitizers. Phosphorescence of the Pt(II) coordination framework (ΦP = 11.0%) is quenched in the anthryl-containing complexes (ΦP = 4.0%) and shows a biexponential decay (τP = 3.4 µs/87% and 18.2 µs/13%) compared to the single-exponential decay of the native Pt(II) Schiff base complex (τP = 3.7 µs). Femtosecond/nanosecond transient absorption spectroscopy suggests an equilibrium between triplet anthracene (3An) and triplet metal-to-ligand charge-transfer (3MLCT) states, with the dark 3An state slightly lower in energy (1.96 eV for Pt-9An and 1.90 eV for Pt-2An) than the emissive 3MLCT state (1.97 eV for Pt-9An and 1.91 eV for Pt-2An). Intramolecular triplet-triplet energy transfer (TTET) and reverse TTET take 4.8 ps/444 ps for Pt-9An and 55 ps/1.7 ns for Pt-2An, respectively. The triplet-state equilibrium extends the triplet-state lifetime of the complexes to 103 µs (Pt-2An) or 163 µs (Pt-9An), in comparison to the native Pt(II) complex, which shows a lifetime of 4.0 µs. The complexes were used for triplet-triplet-annihilation upconversion with perylene as the triplet acceptor. The upconversion quantum yield is up to 15%, and a large anti-Stokes shift (0.75 eV) is achieved by excitation into the singlet metal-to-ligand charge-transfer absorption band (589 nm) of the complexes (anti-Stokes shift is 0.92 eV with 9,10-diphenylanthracene as the acceptor).
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Herein, we establish a simple synthetic strategy affording a heterogeneous, precious metal-free, dye-sensitized photoelectrode for water oxidation, which incorporates a Prussian blue (PB) structure for the sensitization of TiO2 and water oxidation catalysis. Our approach involves the use of a Fe(CN)5 bridging group not only as a cyanide precursor for the formation of a PB-type structure but also as an electron shuttle between an organic chromophore and the catalytic center. The resulting hetero-functional PB-modified TiO2 electrode demonstrates a low-cost and easy-to-construct photoanode, which exhibits favorable electron transfers with a remarkable excited state lifetime on the order of nanoseconds and an extended light absorption capacity of up to 500â nm. Our approach paves the way for a new family of precious metal-free robust dye-sensitized photoelectrodes for water oxidation, in which a variety of common organic chromophores can be employed in conjunction with CoFe PB structures.
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The purpose of this study was to determine the suitability of coffee silverskin (CSS) supplementation to enhance phenolic content and antioxidant capacity of cookies. Cookie samples were prepared with partial replacement of wheat flour by CSS (2.5, 5.0, and 7.5%). Spread ratios were found lower in all cookies with CSS than in control. Cookies became darker with increasing levels of CSS. This is due to the fact that CSS has a dark color like cocoa. CSS supplementation had improved functional quality of cookies by increasing phenolic contents, antioxidant capacities, and in vitro bioaccessibilities of them. According to the sensory evaluation, all samples with CSS received 6 and above scores (6: like slightly, 7: like moderately) for all attributes from the panelists. The results demonstrated that CSS supplementation have a good potential for developing functional and acceptable cookies and similar bakery products.
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A compact naphthalenediimide (NDI)-2,2,6,6-tetramethylpiperidinyloxy (TEMPO) dyad has been prepared with the aim of studying radical-enhanced intersystem crossing (EISC) and the formation of high spin states as well as electron spin polarization (ESP) dynamics. Compared with the previously reported radical-chromophore dyads, the present system shows a very high triplet state quantum yield (ΦT =74 %), a long-lived triplet state (τT =8.7â µs), fast EISC (1/kEISC =338â ps), and absorption in the red spectral region. Time-resolved electron paramagnetic resonance (TREPR) spectroscopy showed that, upon photoexcitation in fluid solution at room temperature, the D0 state of the TEMPO moiety produces strong emissive (E) polarization owing to the quenching of the excited singlet state of NDI by the radical moiety (electron exchange J>0). The emissive polarization then inverts into absorptive (A) polarization within about 3â µs, and then relaxes to a thermal equilibrium while quenching the triplet state of NDI. The formation and decay of the quartet state were also observed. The dyad was used as a three-spin triplet photosensitizer for triplet-triplet annihilation upconversion (quantum yield ΦUC =2.6 %). Remarkably, when encapsulated into liposomes, the red-light-absorbing dyad-liposomes show good biocompatibility and excellent photodynamic therapy efficiency (phototoxicity EC50 =3.22â µm), and therefore is a promising candidate for future less toxic and multifunctional photodynamic therapeutic reagents.
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Óxidos N-Cíclicos/química , Imidas/química , Naftalenos/química , Fármacos Fotossensibilizantes/química , Sobrevivência Celular/efeitos dos fármacos , Técnicas Eletroquímicas , Espectroscopia de Ressonância de Spin Eletrônica , Células HeLa , Humanos , Luz , Lipossomos/química , Lipossomos/metabolismo , Microscopia Confocal , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Teoria Quântica , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Fluorescência , TermodinâmicaRESUMO
An analytical method is presented for the determination of paraben preservatives in semisolid cream samples by matrix solid-phase dispersion combined with supramolecular solvent-based microextraction. Due to the oily and sticky nature of the sample matrix, parabens were first extracted from the samples by matrix solid-phase dispersion using silica as sorbent material with a clean-up performed with tetrahydrofuran in the elution step. The eluate (500 µL), 1-decanol (120 µL), and water (4.4 mL) were then mixed in a polyethylene pipette to form supramolecular solvent. Finally, the analytes in the supramolecular solvent were separated and determined by liquid chromatography with ultraviolet detection. Under optimal extraction conditions, the extraction recoveries of the studied compounds were obtained in the range of 63-83%. The limits of detection for the analytes were between 0.03 and 0.04 µg/g. The precision of the method varied between 4.0-6.7 (intraday) and 6.2-7.9% (interday). Finally, the optimized procedure was applied to the determination of the target preservatives in a variety of cream samples (diaper rash, skin allergy, face and hand moisturizing) with satisfactory recoveries (86-102%).