The direct generation of efficient, tunable, and switchable circularly polarized laser emission (CPLE) would have far-reaching implications in photonics and material sciences. In this paper, we ...describe the first chiral simple organic molecules (SOMs) capable of simultaneously sustaining significant chemical robustness, high fluorescence quantum yields, and circularly polarized luminescence (CPL) ellipticity levels (|g lum|) comparable to those of similar CPL-SOMs. All these parameters altogether enable efficient laser emission and CPLE with ellipticity levels 2 orders of magnitude stronger than the intrinsic CPL ones.
A general and straightforward method for the synthesis of COO-BODIPYs from F-BODIPYs and carboxylic acids is established. The method is based on the use of boron trichloride to activate the involved ...substitution of fluorine, which leads to high yields through rapid reactions under soft conditions. This mild method opens the way to unprecedented laser dyes with outstanding efficiencies and photostabilities, which are difficult to obtain by the current methods.
The search for long‐lived red and NIR fluorescent dyes is challenging and hitherto scarcely reported. Herein, the viability of aza‐BODIPY skeleton as a promising system for achieving thermal ...activated delayed fluorescent (TADF) probes emitting in this target region is demonstrated for the first time. The synthetic versatility of this scaffold allows the design of energy and charge transfer cassettes modulating the stereoelectronic properties of the energy donors, the spacer moieties and the linkage positions. Delayed emission from these architectures is recorded in the red spectral region (695–735 nm) with lifetimes longer than 100 μs in aerated solutions at room temperature. The computational‐aided photophysical study under mild and hard irradiation regimes disclose the interplay between molecular structure and photonic performance to develop long‐lived fluorescence red emitters through thermally activated reverse intersystem crossing. The efficient and long‐lasting NIR emission of the newly synthesized aza‐BODIPY systems provides a basis to develop advanced optical materials with exciting and appealing photonic response.
Long‐lived NIR fluorescence: Aza‐BODIPYs are attractive source of NIR fluorescence and laser emission. Herein, their ability to display delayed fluorescence via RISC under hard irradiation regimes is demonstrated for the first time. The designed cassettes are appealing materials endowed with efficient and long‐lasting prompt NIR emission and with long‐lived delayed emission (hundreds of microseconds) even in aerated solutions at room temperature.
The generation of circularly polarized laser emission (CPLE) in photonic devices has attracted increasing attention due to the prospects of using CP light in displaying technologies or advanced ...microscopies. Organic systems excel as laser materials across the whole visible spectrum, and despite many of them displaying circularly polarized luminescence (CPL), none have been shown thus far to amplify their own CPL, let alone generate CPLE. Consequently, there is still a need to find alternative CPLE organic devices. Herein we demonstrate an effective strategy for achieving strong levels of CPLE (|g
| ∼ 0.1-0.2) by using solutions of an achiral dye dissolved in optically active solvents to exploit the full potential of the dynamic birefringence induced by the intense and polarized laser pumping. The present approach enables changing the CPLE handedness by changing the handedness of the solvent optical activity, opening new avenues for developing cost-effective and easily processable chiro-photonic materials.
We have established an easy synthetic protocol for selectively developing all-orthogonal BODIPY trimers with unprecedented geometries on the basis of selecting methyl oxidation versus electrophilic ...formylation of key dimeric precursors. Photophysical characterization together with biological assays unraveled the most suitable BODIPY–BODIPY geometrical arrangements within the trimer, forcing them to serve as molecular platforms for the development of new, advanced heavy-atom-free photosensitizers for photodynamic therapy and phototheragnosis.
Generation of triplet states in assemblies of organic chromophores is extremely appealing for their potential use in optoelectronic applications. In this work, we investigate the intricacies of ...triplet state generation in an orthogonal BODIPY dimer by combining delayed photoemission techniques with electronic structure calculations. Our analysis provides a deep understanding of the electronic states involved, and describes different competing deactivation channels beyond prompt radiative decay. In particular, we identify charge-transfer (CT) mediated intersystem crossing (ISC) as the most likely mechanism for the triplet state generation in this system. The different emission bands at long times can be associated with delayed fluorescence, CT emission and phosphorescence from multiple low-energy triplets. Interestingly, the dependence of the yield of triplet state population and emission profiles with the solvent polarity evidences the decisive role of the CT configuration in the fate of the photoactivated dimer, controlling the relative ISC, reverse ISC, and internal conversion efficiencies. Overall, the present results provide a rather complete description of the delayed photophysics in the BODIPY dimer, but are not able to fully rationalize the unexpected photoluminescence recorded at long wavelengths (≥ 900 nm). We hypothesize that the origin of this emission, not present in BODIPY monomers, emerges from intermonomer interactions triggered by intramolecular distortions opening up a new vision in the controverted mechanism driving the photophysical behavior from orthogonally linked organic monomers.
A series of fluorescent boron‐dipyrromethene (BODIPY, 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene) dyes have been designed to participate, as aglycons, in synthetic oligosaccharide protocols. As such, ...they served a dual purpose: first, by being incorporated at the beginning of the process (at the reducing‐end of the growing saccharide moiety), they can function as fluorescent glycosyl tags, facilitating the detection and purification of the desired glycosidic intermediates, and secondly, the presence of these chromophores on the ensuing compounds grants access to fluorescently labeled saccharides. In this context, a sought‐after feature of the fluorescent dyes has been their chemical robustness. Accordingly, some BODIPY derivatives described in this work can withstand the reaction conditions commonly employed in the chemical synthesis of saccharides; namely, glycosylation and protecting‐group manipulations. Regarding their photophysical properties, the BODIPY‐labeled saccharides obtained in this work display remarkable fluorescence efficiency in water, reaching quantum yield values up to 82 %, as well as notable lasing efficiencies and photostabilities.
A colorful solution: Boron‐dipyrromethene (BODIPY) fluorophores, conveniently substituted, can endure most of the reaction conditions involved in synthetic sequences leading to oligosaccharides. Thus, BODIPY dyes could be used as aglycons in synthetic routes leading to fluorescently labeled saccharides. Accordingly, BODIPYs display a dual role: as colorful glycosyl‐tags during the synthesis, and as fluorescent‐labels on the ensuing glycosides.
Chronic endometritis is a persistent inflammation of the endometrial mucosa caused by bacterial pathogens such as Enterobacteriaceae, Enterococcus, Streptococcus, Staphylococcus, Mycoplasma, and ...Ureaplasma. Although chronic endometritis can be asymptomatic, it is found in up to 40% of infertile patients and is responsible for repeated implantation failure and recurrent miscarriage. Diagnosis of chronic endometritis is based on hysteroscopy of the uterine cavity, endometrial biopsy with plasma cells being identified histologically, while specific treatment is determined based on microbial culture. However, not all microorganisms implicated are easily or readily culturable needing a turnaround time of up to 1 week.
We sought to develop a molecular diagnostic tool for chronic endometritis based on real-time polymerase chain reaction equivalent to using the 3 classic methods together, overcoming the bias of using any of them alone.
Endometrial samples from patients assessed for chronic endometritis (n = 113) using at least 1 or several conventional diagnostic methods namely histology, hysteroscopy, and/or microbial culture, were blindly evaluated by real-time polymerase chain reaction for the presence of 9 chronic endometritis pathogens: Chlamydia trachomatis, Enterococcus, Escherichia coli, Gardnerella vaginalis, Klebsiella pneumoniae, Mycoplasma hominis, Neisseria gonorrhoeae, Staphylococcus, and Streptococcus. The sensitivity and specificity of the molecular analysis vs the classic diagnostic techniques were compared in the 65 patients assessed by all 3 recognized classic methods.
The molecular method showed concordant results with histological diagnosis in 30 samples (14 double positive and 16 double negative) with a matching accuracy of 46.15%. Concordance of molecular and hysteroscopic diagnosis was observed in 38 samples (37 double positive and 1 double negative), with an accuracy of 58.46%. When the molecular method was compared to microbial culture, concordance was present in 37 samples (22 double positive and 15 double negative), a matching rate of 56.92%. When cases of potential contamination and/or noncultivable bacteria were considered, the accuracy increased to 66.15%. Of these 65 patients, only 27 patients had consistent histological + hysteroscopic diagnosis, revealing 58.64% of nonconcordant results. Only 13 of 65 patients (20%) had consistent histology + hysteroscopy + microbial culture results. In these cases, the molecular microbiology matched in 10 cases showing a diagnostic accuracy of 76.92%. Interestingly, the molecular microbiology confirmed over half of the isolated pathogens and provided additional detection of nonculturable microorganisms. These results were confirmed by the microbiome assessed by next-generation sequencing. In the endometrial samples with concordant histology + hysteroscopy + microbial culture results, the molecular microbiology diagnosis demonstrates 75% sensitivity, 100% specificity, 100% positive and 25% negative predictive values, and 0% false-positive and 25% false-negative rates.
The molecular microbiology method describe herein is a fast and inexpensive diagnostic tool that allows for the identification of culturable and nonculturable endometrial pathogens associated with chronic endometritis. The results obtained were similar to all 3 classic diagnostic methods together with a degree of concordance of 76.92% providing an opportunity to improve the clinical management of infertile patients with a risk of experiencing this ghost endometrial pathology.
COO-BODIPYs are highlighted as cutting edge scaffolds for easy access to a new generation of multichromophoric architectures with enhanced (photo)chemical stability, showing either boosted capability ...for excitation energy transfer, glow fluorescence and laser emission, or photoinduced electron transfer. The new finding paves the way for the rapid development of smarter organic dyes for advancing photonics and optoelectronics.
Synthesis and photonics avails a new design for multichromophoric arrays.
The development of highly efficient and stable blue‐emitting dyes to overcome some of the most important shortcomings of available chromophores is of great technological importance for modern ...optical, analytical, electronic, and biological applications. Here, we report the design, synthesis and characterization of new tailor‐made BODIPY dyes with efficient absorption and emission in the blue spectral region. The major challenge is the effective management of the electron‐donor strength of the substitution pattern, in order to modulate the emission of these novel dyes over a wide spectral range (430–500 nm). A direct relationship between the electron‐donor character of the substituent and the extension of the spectral hypsochromic shift is seen through the energy increase of the LUMO state. However, when the electron‐donor character of the substituent is high enough, an intramolecular charge‐transfer process appears to decrease the fluorescence ability of these dyes, especially in polar media. Some of the reported novel BODIPY dyes provide very high fluorescence quantum yields, close to unity, and large Stokes shifts, leading to highly efficient tunable dye lasers in the blue part of the spectrum; this so far remains an unexploited region with BODIPYs. In fact, under demanding transversal pumping conditions, the new dyes lase with unexpectedly high lasing efficiencies of up to 63 %, and also show high photostabilities, outperforming the laser action of other dyes considered as benchmarks in the same spectral region. Considering the easy synthetic protocol and the wide variety of possible substituents, we are confident that this strategy could be successfully extended for the development of efficient blue‐edge emitting materials and devices, impelling biophotonic and optoelectronic applications.
So simple, so efficient, and so blue: 8‐Amino‐BODIPY dyes were prepared in a straightforward and efficient fashion (up to 95 % yield). They emit in the blue spectral region (see figure) with ϕ values up to 1.00, high laser efficiencies (up to 62 %), and good photostabilities. These results demonstrate that these new tailor‐made chromophores can overcome some of the shortcomings of commercial blue‐emitting dyes.
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