Telomerase is essential for cardiac differentiation and sustained metabolism of human cardiomyocytes.

Telomeres as the protective ends of linear chromosomes, are synthesized by the enzyme telomerase (TERT). Critically short telomeres essentially contribute to aging-related diseases and are associated with a broad spectrum of disorders known as telomeropathies. In cardiomyocytes, telomere length is strongly correlated with cardiomyopathies but it remains ambiguous whether short telomeres are the cause or the result of the disease. In this study, we employed an inducible CRISPRi human induced pluripotent stem cell (hiPSC) line to silence TERT expression enabling the generation of hiPSCs and hiPSC-derived cardiomyocytes with long and short telomeres. Reduced telomerase activity and shorter telomere lengths of hiPSCs induced global transcriptomic changes associated with cardiac developmental pathways. Consequently, the differentiation potential towards cardiomyocytes was strongly impaired and single cell RNA sequencing revealed a shift towards a more smooth muscle cell like identity in the cells with the shortest telomeres. Poor cardiomyocyte function and increased sensitivity to stress directly correlated with the extent of telomere shortening. Collectively our data demonstrates a TERT dependent cardiomyogenic differentiation defect, highlighting the CRISPRi TERT hiPSCs model as a powerful platform to study the mechanisms and consequences of short telomeres in the heart and also in the context of telomeropathies.

Combined Nucleophilic and Electrophilic Functionalization to Optimize Blue Phosphorescence in Cyclometalated Platinum Complexes.

Ligand-based functionalization strategies have emerged as powerful approaches to tune and optimize blue phosphorescence, which can involve nucleophilic addition to coordinated ligands or electrophilic functionalization via the coordination of exogenous Lewis acids. Whereas both have been used separately to enhance the photophysical properties of organometallic compounds with high-energy triplet states, in this work, we show that these two strategies can be used together on the same platform. Isocyanide-supported cyclometalated platinum compounds undergo nucleophilic addition with diethylamine to form a strong σ-donor acyclic diaminocarbene-supporting ligand. In a subsequent step, a cyanide ancillary ligand is converted into a more strongly π-acidic isocyanoborate via the coordination of a borane Lewis acid. Importantly, both of these ligand-based functionalization steps improve the quantum yields and lifetimes of the blue-phosphorescent complexes. This synergy results in complexes with photoluminescence quantum yields up to 0.40 for deep blue and 0.75 for sky blue regions and PL lifetimes on the order of 10-5 s.

A study on a broadband photodetector based on hybrid 2D copper oxide/reduced graphene oxide.

These days, photodetectors are a crucial part of optoelectronic devices, ranging from environmental monitoring to international communication systems. Therefore, fabricating these devices at a low cost but obtaining high sensitivity in a wide range of wavelengths is of great interest. This report introduces a simple solution-processed hybrid 2D structure of CuO and rGO for broadband photodetector applications. Particularly, 2D CuO acts as the active material, absorbing light to generate electron-hole pairs, while 2D rGO plays the role of a transport layer, driving charge carriers between two electrodes. Our device exhibits remarkable sensitivity to a wide wavelength range from 395 nm to 945 nm (vis-NIR region). Interestingly, our devices' responsivity and photoconductive gain were calculated (under 395 nm wavelength excitation) to be up to 8 mA W-1 and 28 fold, respectively, which are comparable values with previous publications. Our hybrid 2D structure between rGO and CuO enables a potential approach for developing low-cost but high-performance optoelectronic devices, especially photodetectors, in the future.

Computationally defined and in vitro validated putative genomic safe harbour loci for transgene expression in human cells.

Selection of the target site is an inherent question for any project aiming for directed transgene integration. Genomic safe harbour (GSH) loci have been proposed as safe sites in the human genome for transgene integration. Although several sites have been characterised for transgene integration in the literature, most of these do not meet criteria set out for a GSH and the limited set that do have not been characterised extensively. Here, we conducted a computational analysis using publicly available data to identify 25 unique putative GSH loci that reside in active chromosomal compartments. We validated stable transgene expression and minimal disruption of the native transcriptome in three GSH sites in vitro using human embryonic stem cells (hESCs) and their differentiated progeny. Furthermore, for easy targeted transgene expression, we have engineered constitutive landing pad expression constructs into the three validated GSH in hESCs.

Improved transition metal photosensitizers to drive advances in photocatalysis.

To function effectively in a photocatalytic application, a photosensitizer's light absorption, excited-state lifetime, and redox potentials, both in the ground state and excited state, are critically important. The absorption profile is particularly relevant to applications involving solar harvesting, whereas the redox potentials and excited-state lifetimes determine the thermodynamics, kinetics, and quantum yields of photoinduced redox processes. This perspective article focuses on synthetic inorganic and organometallic approaches to optimize these three characteristics of transition-metal based photosensitizers. We include our own work in these areas, which has focused extensively on exceptionally strong cyclometalated iridium photoreductants that enable challenging reductive photoredox transformations on organic substrates, and more recent work which has led to improved solar harvesting in charge-transfer copper(i) chromophores, an emerging class of earth-abundant compounds particularly relevant to solar-energy applications. We also extensively highlight many other complementary strategies for optimizing these parameters and highlight representative examples from the recent literature. It remains a significant challenge to simultaneously optimize all three of these parameters at once, since improvements in one often come at the detriment of the others. These inherent trade-offs and approaches to obviate or circumvent them are discussed throughout.

A visible-light photodetector based on heterojunctions between CuO nanoparticles and ZnO nanorods.

Optoelectronic devices have various applications in medical equipment, sensors, and communication systems. Photodetectors, which convert light into electrical signals, have gained much attention from many research teams. This study describes a low-cost photodetector based on CuO nanoparticles and ZnO nanorods operating in a wide range of light wavelengths (395, 464, 532, and 640 nm). Particularly, under 395 nm excitation, the heterostructure device exhibits high responsivity, photoconductive gain, detectivity, and sensitivity with maximum values of 1.38 A·W-1, 4.33, 2.58 × 1011 Jones, and 1934.5% at a bias of 2 V, respectively. The sensing mechanism of the p-n heterojunction of CuO/ZnO is also explored. Overall, this study indicates that the heterostructure of CuO nanoparticles and ZnO nanorods obtained via a simple and cost-effective synthesis process has great potential for optoelectronic applications.

Sterically Encumbered Heteroleptic Copper(I) ß-Diketiminate Complexes with Extended Excited-State Lifetimes.

One of the main challenges in developing effective copper(I) photosensitizers is their short excited-state lifetimes, usually attributed to structural distortion upon light excitation. We have previously introduced copper(I) charge-transfer chromophores of the general formula Cu(N^N)(ArNacNac), where N^N is a conjugated diimine ligand and ArNacNac is a substituted ß-diketiminate ligand. These chromophores were promising regarding their tunable redox potentials and intense visible absorption but were ineffective as photosensitizers, presumably due to short excited-state lifetimes. Here, we introduce sterically crowded analogues of these heteroleptic chromophores with bulky alkyl substituents on the N^N and/or ArNacNac ligand. Structural analysis was combined with electrochemical and photophysical characterization, including ultrafast transient absorption (UFTA) spectroscopy to investigate the effects of the alkyl groups on the excited-state lifetimes of the complexes. The molecular structures determined by single-crystal X-ray diffraction display more distortion in the ground state as alkyl substituents are introduced into the phenanthroline or the NacNac ligand, showing smaller τ4 values due to the steric hindrance. UFTA measurements were carried out to determine the excited-state dynamics. Sterically encumbered Cu5 and Cu6 display excited-state lifetimes 15-20 times longer than unsubstituted complex Cu1, likely indicating that the incorporation of bulky alkyl substituents inhibits the pseudo-Jahn-Teller (PJT) flattening distortion in the excited state. This work suggests that the steric properties of these heteroleptic copper(I) charge-transfer chromophores can be readily modified and that the excited-state dynamics are strongly responsive to these modifications.

Splenic ectopic pregnancy: Rare location of ectopic pregnancy, how does it present?

Splenic ectopic pregnancy (SEP) is a rare high-mortality condition, particularly relating to life-threatening intraperitoneal bleeding due to a high risk of spontaneous rupture. Diagnosing in a timely fashion is extremely crucial and the patients could benefit from active treatment strategies and early management. In this article, we reviewed a case of 40 years-old female who complained of lower quadrant abdominal pain and amenorrhea with a history of intrauterine device (IUD) insertion for over 6 years. Elevating b-human chorionic gonadotropin (HCG) blood levels were documented, raising concern about pregnancy-related emergency conditions. Ultrasound and magnetic resonance imaging results suggested a splenic ectopic pregnancy entity with a high rupture rate. The patient subsequently underwent laparoscopic resection for splenic mass removal. Ectopic pregnancy should cautiously be excluded in all cases of abdominal pain in childbearing-age women.

Reductive photoredox transformations of carbonyl derivatives enabled by strongly reducing photosensitizers.

Visible-light photoredox catalysis is well-established as a powerful and versatile organic synthesis strategy. However, some substrate classes, despite being attractive precursors, are recalcitrant to single-electron redox chemistry and thus not very amenable to photoredox approaches. Among these are carbonyl derivatives, e.g. ketones, aldehydes, and imines, which in most cases require Lewis or Brønsted acidic additives to activate via photoinduced electron transfer. In this work, we unveil a range of photoredox transformations on ketones and imines, enabled by strongly reducing photosensitizers and operating under simple, general conditions with a single sacrificial reductant and no additives. Specific reactions described here are umpolung C-C bond forming reactions between aromatic ketones or imines and electron-poor alkenes, imino-pinacol homocoupling reactions of challenging alkyl-aryl imine substrates, and γ-lactonization reactions of aromatic ketones with methyl acrylate. The reactions are all initiated by photoinduced electron transfer to form a ketyl or iminyl that is subsequently trapped.

Complementary HLH susceptibility factors converge on CD8 T-cell hyperactivation.

Hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening hyperinflammatory syndromes. Familial HLH is caused by genetic impairment of granule-mediated cytotoxicity (eg, perforin deficiency). MAS is linked to excess activity of the inflammasome-activated cytokine interleukin-18 (IL-18). Though individually tolerated, mice with dual susceptibility (Prf1⁻/⁻Il18tg; DS) succumb to spontaneous, lethal hyperinflammation. We hypothesized that understanding how these susceptibility factors synergize would uncover key pathomechanisms in the activation, function, and persistence of hyperactivated CD8 T cells. In IL-18 transgenic (Il18tg) mice, IL-18 effects on CD8 T cells drove MAS after a viral (lymphocytic choriomeningitis virus), but not innate (toll like receptor 9), trigger. In vitro, CD8 T cells also required T-cell receptor (TCR) stimulation to fully respond to IL-18. IL-18 induced but perforin deficiency impaired immunoregulatory restimulation-induced cell death (RICD). Paralleling hyperinflammation, DS mice displayed massive postthymic oligoclonal CD8 T-cell hyperactivation in their spleens, livers, and bone marrow as early as 3 weeks. These cells increased proliferation and interferon gamma production, which contrasted with increased expression of receptors and transcription factors associated with exhaustion. Broad-spectrum antibiotics and antiretrovirals failed to ameliorate the disease. Attempting to genetically "fix" TCR antigen-specificity instead demonstrated the persistence of spontaneous HLH and hyperactivation, chiefly on T cells that had evaded TCR fixation. Thus, drivers of HLH may preferentially act on CD8 T cells: IL-18 amplifies activation and demand for RICD, whereas perforin supplies critical immunoregulation. Together, these factors promote a terminal CD8 T-cell activation state, combining features of exhaustion and effector function. Therefore, susceptibility to hyperinflammation may converge on a unique, unrelenting, and antigen-dependent state of CD8 T-cell hyperactivation.

Intracytoplasmic sperm injection versus conventional in vitro fertilisation in couples with males presenting with normal total sperm count and motility.

BACKGROUND: Starting over 40 years ago, in vitro fertilisation (IVF) has become the cornerstone for fertility treatment. Since then, in 1992, Palermo and colleagues successfully applied the technique intracytoplasmic sperm injection (ICSI) to benefit couples where conventional in vitro fertilisation (c-IVF) and sub-zonal insemination (SUZI) proved unsuccessful. After this case report, ICSI has become the treatment of choice for couples with severe male factor subfertility. Over time, ICSI has been used in the treatment of couples with mild male and even unexplained infertility. This review is an update of the review, first published in 1999, comparing ICSI with c-IVF for couples with males presenting with normal total sperm count and motility. OBJECTIVES: To evaluate the effectiveness and safety of ICSI relative to c-IVF in couples with males presenting with normal total sperm count and motility. SEARCH METHODS: We searched the following databases and trial registers: Cochrane Central Register of Controlled Trials (CENTRAL), Embase (excerpta Medica Database), MEDLINE (Medical Literature Analysis and Retrieval System Online) and PsycINFO (Psychological literature database) for articles between January 2010 and 22 February 2023. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared ICSI with c-IVF in couples with males presenting with normal total sperm count and motility. DATA COLLECTION AND ANALYSIS: We used standard methodical procedures recommended by Cochrane. The primary review outcomes were live birth and adverse events. Secondary outcomes included clinical pregnancy, viable intrauterine pregnancy and miscarriage. MAIN RESULTS: The original review published in 2003 included one RCT. In this 2023 update, we identified an additional two RCTs totalling a cohort of 1539 couples, comparing ICSI with c-IVF techniques. Two studies reported on live birth. Using the GRADE method, we assessed the certainty of evidence and reported evidence as low-certainty for live birth. We are uncertain of the effect of ICSI versus c-IVF for live birth rates (risk ratio (RR) 1.11, 95% confidence interval (CI 0.94 to 1.30, I2 = 0%, 2 studies, n = 1124, low-certainty evidence). The evidence suggests that if the chance of live birth following c-IVF is assumed to be 32%, the chance of live birth with ICSI would be between 30% and 41%. For adverse events; multiple pregnancy, ectopic pregnancy, pre-eclampsia and prematurity, there was probably little or no difference between the two techniques. No study reported the primary outcome stillbirth. For secondary outcomes, we are uncertain of the effect of ICSI versus c-IVF for clinical pregnancy rates (RR 1.00, 95% CI 0.88 to 1.13, I2 = 45%, 3 studies, n = 1539, low-certainty evidence). Comparison of viable intrauterine pregnancy rates showed probably little or no difference between ICSI and c-IVF (RR 1.00, 95% CI 0.86 to 1.16, I2=75%, 2 studies, n = 1479 couples, moderate-certainty evidence). The high heterogeneity may have been caused by one older study conducted when protocols were less rigorous. The evidence suggests that if the chance of viable intrauterine pregnancy following c-IVF is assumed to be 33%, the chance of viable intrauterine pregnancy with ICSI would be between 28% and 38%. Miscarriage rates also showed probably little or no difference between the two techniques. AUTHORS' CONCLUSIONS: The current available studies that compare ICSI and c-IVF in couples with males presenting with normal total sperm count and motility, show neither method was superior to the other, in achieving live birth, adverse events (multiple pregnancy, ectopic pregnancy, pre-eclampsia and prematurity), also alongside secondary outcomes, clinical pregnancy, viable intrauterine pregnancy or miscarriage.

Endocytosis of red blood cell extracellular vesicles by macrophages leads to cytoplasmic heme release and prevents foam cell formation in atherosclerosis.

Extracellular vesicles (EVs) can be produced from red blood cells (RBCs) on a large scale and used to deliver therapeutic payloads efficiently. However, not much is known about the native biological properties of RBCEVs. Here, we demonstrate that RBCEVs are primarily taken up by macrophages and monocytes. This uptake is an active process, mediated mainly by endocytosis. Incubation of CD14+ monocytes with RBCEVs induces their differentiation into macrophages with an Mheme-like phenotype, characterized by upregulation of heme oxygenase-1 (HO-1) and the ATP-binding cassette transporter ABCG1. Moreover, macrophages that take up RBCEVs exhibit a reduction in surface CD86 and decreased secretion of TNF-α under inflammatory stimulation. The upregulation of HO-1 is attributed to heme derived from haemoglobin in RBCEVs. Heme is released from internalized RBCEVs in late endosomes and lysosomes via the heme transporter, HRG1. Consequently, RBCEVs exhibit the ability to attenuate foam cell formation from oxidized low-density lipoproteins (oxLDL)-treated macrophages in vitro and reduce atherosclerotic lesions in ApoE knockout mice on a high-fat diet. In summary, our study reveals the uptake mechanism of RBCEVs and their delivery of heme to macrophages, suggesting the potential application of RBCEVs in the treatment of atherosclerosis.

Developing low-cost nanohybrids of ZnO nanorods and multi-shaped silver nanoparticles for broadband photodetectors.

Photodetectors are essential elements for various applications like fiber optic communication systems, biomedical imaging, and so on. Thus, improving the performance and reducing the material costs of photodetectors would act as a motivation toward the future advancement of those applications. This study introduces the development of a nanohybrid of zinc oxide nanorods (ZnONRs) and multi-shaped silver nanoparticles MAgNPs through a simple solution process; in which ZnONRs are hybridized with MAgNPs to enable visible absorption through the surface plasmon resonance (SPR) effect. The photodetector based on ZnONRs/MAgNPs is responsive to visible light with representative wavelengths of 395, 464, 532 and 640 nm, and it exhibits high responsivity (R), photoconductive gain (G) and detectivity (D). The maximum R is calculated from the fitting curve of the responsivity-power relation with the value of 5.35 × 103 (mA W-1) at 395 nm excitation. The highest G and D reach 8.984 and 3.71 × 1010 Jones at that wavelength. This reveals the promise of our innovative broadband photodetector for practical usage.

PROMPT: Prospective Meta-analysis for Pessary Trials Study Protocol.

OBJECTIVE: Preterm birth, defined as birth before 37 weeks of gestation, is a leading cause of perinatal and infant mortality throughout the world. Preterm birth is also associated with long-term neurological disabilities and other significant health issues in children. A short cervix in the second trimester has been noted to be one of the strongest predictors of subsequent spontaneous preterm birth in both singleton and multiple pregnancies. Some studies have shown that cervical support in the form of an Arabin pessary lowers the risk of preterm birth in women with a singleton gestation and short cervical length; however, other studies have conflicting results. Our objective was to form an international collaborative of planned or ongoing randomized trials of pessary in singleton and twin gestations with a short cervix. STUDY DESIGN: In November 2014, an international group of investigators, who had initiated or were planning randomized trials of pessary for pregnant people with a short cervix and singleton or twin gestation to prevent preterm birth, formed a collaboration to plan a prospective individual patient data (IPD) meta-analysis of randomized trials (PROspective Meta-analysis of Pessary Trials [PROMPT]). The PROMPT investigators agreed on meta-analysis IPD hypotheses for singletons and twins, eligibility criteria, and a set of core baseline and outcome measures. The primary outcome is a composite of fetal death or preterm delivery before 32 weeks' gestation. Secondary outcomes include maternal and neonatal morbidities. The PROMPT protocol may be viewed as a written agreement among the study investigators who make up the PROMPT consortium (PROSPERO ID# CRD42018067740). RESULTS: Results will be published in phases as the individual participating studies are concluded and published. Results of the first phase of singleton and twin pessary trials are expected to be available in late 2022. Updates are planned as participating trials are completed and published. KEY POINTS: · Short cervical length predicts preterm birth.. · Results of prior cervical pessary trials are mixed.. · Meta-analysis of pessary trials protocol..

Chemical composition, anti-inflammatory and cytotoxic activity of essential oils from two Luvunga species (L. scandens and L. hongiaoensis) from Vietnam.

New essential oils (EOs) extracted from different parts of two Luvunga species (L. scandens and L. hongiaoensis) from Vietnam were investigated for their chemical composition, anti-inflammatory and cytotoxic activity. Sixty-nine total compounds were identified in the EOs by GC/MS. The major constituent of the leaf, fruit, and root EOs from L. scandens was ß-caryophyllene (71.5%, 63.0%, and 31.5% respectively). The main compounds in L. hongiaoensis EOs were ß-elemene (34.3% in leaf oil) and caryophyllene oxide (21.2% in root oil, 19.4% in stem oil). The EO from L. scandens fruits significantly inhibited nitric oxide production on LPS-induced RAW264.7 cells (IC50 = 37.95 ± 2.76 µg/mL). The EOs from L. hongiaoensis roots and L. scandens leaves and fruits exhibited cytotoxic activity against MCF-7, SK-LU-1, and HepG2 (IC50 from 49.74 ± 3.36 to 97.82 ± 8.61 µg/mL). This is the first report on L. hongiaoensis EOs and significantly complements the composition and bioactivity of L. scandens EOs.

Efficient blue-phosphorescent trans-bis(acyclic diaminocarbene) platinum(ii) acetylide complexes.

The lack of efficient and robust deep-blue phosphorescent metal complexes remains a significant challenge in the context of electroluminescent color displays. The emissive triplet states of blue phosphors are deactivated by low-lying metal-centered (3MC) states, which can be ameliorated by increasing the σ-donating ability of the supporting ligands. Here we unveil a synthetic strategy to access blue-phosphorescent complexes with two supporting acyclic diaminocarbenes (ADCs), known to be even stronger σ-donors than N-heterocyclic carbenes (NHCs). This new class of platinum complexes has excellent photoluminescence quantum yields, with four of six complexes affording deep-blue emission. Experimental and computational analyses are consistent with a pronounced destabilization of the 3MC states by the ADCs.

Development of children born to women with twin pregnancies treated with cervical pessary or vaginal progesterone: Follow-up of a randomized controlled trial.

INTRODUCTION: Preterm birth is the most common cause of neonatal morbidity and mortality. Women with twin pregnancies and a short cervical length are at high risk for preterm birth. Vaginal progesterone and cervical pessary have been proposed as potential strategies to reduce preterm birth in this high-risk population. Therefore, we aimed to compare the effectiveness of cervical pessary and vaginal progesterone in improving developmental outcomes of children born to women with twin pregnancies and mid-trimester short cervical length. MATERIAL AND METHODS: This was a follow-up study (NCT04295187) of all children at 24 months of age, born from women treated with cervical pessary or progesterone to prevent preterm birth in a randomized controlled trial (NCT02623881). We used a validated Vietnamese version of Ages & Stages Third Edition Questionnaires (ASQ-3) and a red flag questionnaire. In surviving children, we compared the mean ASQ-3 scores, abnormal ASQ-3 scores, the number of children with any abnormal ASQ-3 scores and red flag signs between the two groups. We reported the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in offspring. These outcomes were also calculated in a subgroup of women with a cervical length ≤28 mm (<25th percentile). RESULTS: In the original randomized controlled trial, we randomized 300 women to pessary or progesterone. After counting the number of perinatal deaths and lost to follow-up, 82.8% parents in the pessary group and 82.5% parents in progesterone group returned the questionnaire. The mean ASQ-3 scores of the five skills and red flag signs did not differ significantly between the two groups. However, the percentage of children having abnormal ASQ-3 scores in fine motor skills was significantly lower in the progesterone group (6.1% vs 1.3%, P = 0.01). There were no significant differences in the composite outcome of perinatal death or survival with any abnormal ASQ-3 score in unselected women and in those with cervical length ≤28 mm. CONCLUSIONS: Cervical pessary and vaginal progesterone may have comparable effects on developmental outcomes in children at ≥24 months of age, born to women with twin pregnancies and short cervical length. However, this finding could be likely due to a lack of study power.

Active pulmonary tuberculosis in a patient with secukinumab treatment.

Numerous investigations have documented active tuberculosis (TB) infection following biologic treatment. One of the most secure biologic medications for infections is secukinumab. Additionally, no cases of active TB while receiving secukinumab therapy were recorded. Secukinumab 150 mg per month has been administered for a 19-year-old man with spondyloarthritis since May 2020. A diagnosis of pulmonary TB was made when the patient complained of a moderate fever, a productive cough, and weight loss after 2 years. His fever and respiratory symptoms were relieved after 6 weeks of treatment by stopping secukinumab and utilizing 4 antibiotics: isoniazid, rifampicin, pyrazinamide, and ethambutol, while non-steroidal anti-inflammatory drugs reduced his joint and back discomfort. During biological therapy, even with secukinumab, annual screening for latent and active TB is crucial. We require additional study on secukinumab-treated patients with active TB in nations with high TB burdens, including Vietnam.

Functionalized silver nanoparticles for SERS amplification with enhanced reproducibility and for ultrasensitive optical fiber sensing in environmental and biochemical assays.

Plasmonic sensors have broad application potential in many fields and are promising to replace most bulky sensors in the future. There are various method-based chemical reduction processes for silver nanoparticle production with flexible structural shapes due to their simplicity and rapidity in nanoparticle fabrication. In this study, self-assembled silver nanoparticles (Ag NPs) with a plasmon peak at 424 nm were successfully coated onto -NH2-functionalized glass and optical fiber sensors. These coatings were rapidly produced via two denaturation reactions in plasma oxygen, respectively, and an APTES ((3-aminopropyl)triethoxysilane) solution was shown to have high strength and uniformity. With the use of Ag NPs for surface-enhanced Raman scattering (SERS), excellent results and good stability with the detection limit up to 10-10 M for rhodamine B and 10-8 M for methylene blue, and a signal degradation of only ∼20% after storing for 30 days were achieved. In addition, the optical fiber sensor with Ag NP coatings exhibited a higher sensitivity value of 250 times than without coatings to the glycerol solution. Therefore, significant enhancement of these ultrasensitive sensors demonstrates promising alternatives to cumbersome tests of dye chemicals and biomolecules without any complicated process.

Electrocatalytic CO2 Reduction by [Re(CO)3Cl(3-(pyridin-2-yl)-5-phenyl-1,2,4-triazole)] and [Re(CO)3Cl(3-(2-pyridyl)-1,2,4-triazole)].

The exploration of novel electrocatalysts for CO2 reduction is necessary to overcome global warming and the depletion of fossil fuels. In the current study, the electrocatalytic CO2 reduction of [Re(CO)3Cl(N-N)], where N-N represents 3-(2-pyridyl)-1,2,4-triazole (Hpy), 3-(pyridin-2-yl)-5-phenyl-l,2,4-triazole (Hph), and 2,2'-bipyridine-4,4' dicarboxylic acidic (bpy-COOH) ligands, was investigated. In CO2-saturated electrolytes, cyclic voltammograms showed an enhancement of the current at the second reduction wave for all complexes. In the presence of triethanolamine (TEOA), the currents of Re(Hpy), Re(Hph), and Re(bpy-COOH) enhanced significantly by approximately 4-, 2-, and 5-fold at peak potentials of -1.60, -150, and -1.69 VAg/Ag+, respectively (in comparison to without TEOA). The reduction potential of Re(Hph) was less negative than those of Re(Hpy) and Re(COOH), which was suggested to cause its least efficiency for CO2 reduction. Chronoamperometry measurements showed the stability of the cathodic current at the second reduction wave for at least 300 s, and Re(COOH) was the most stable in the CO2-catalyzed reduction. The appearance and disappearance of the absorption band in the UV/vis spectra indicated the reaction of the catalyst with molecular CO2 and its conversion to new species, which were proposed to be Re-DMF + and Re-TEOA and were supposed to react with CO2 molecules. The CO2 molecules were claimed to be captured and inserted into the oxygen bond of Re-TEOA, resulting in the enhancement of the CO2 reduction efficiency. The results indicate a new way of using these complexes in electrocatalytic CO2 reduction.