Hemiindigo is a long known chromophore that absorbs in the blue part of the spectrum but has almost completely been ignored as potential photoswitch. Herein we show how the absorption of hemiindigo ...is shifted to the red part of the visible spectrum and how nearly perfect photoswitching can be achieved using blue or green and red light. Five derivatives were investigated giving very high isomeric yields in both switching directions, i.e. >90% E isomer after irradiation with 470 to 530 nm light and 99% Z isomer with 590 up to 680 nm light. At the same time the thermal bistability is extraordinarily high leading to half-lives of the pure isomeric states of up to 83 years at 25 °C. The herein developed photoswitches show photochromism in the visible enabling the two isomeric states to be distinguished by the naked eye. Substituted hemiindigos therefore constitute extremely promising new photoswitches with excellent properties for applications in biology, chemistry, or material sciences.
The non-thermal plasma (NTP) technique is an advanced oxidation technology (AOT) applied to the degradation of organic compounds in water. In this study, the degradation kinetics of indigo carmine ...was investigated systematically, applying N2-NTP, O2-NTP, ozonolysis and hydrogen peroxide and the results were compared. The transient species (OH, O and NO radicals) formed with the NTP discharge at the gas-liquid interface and their products (NO3−, NO2−, H2O2) stabilized by the water, were identified and quantified. These species contribute to the effects on the chemical characteristics of the water, such as a decrease in the pH and increase in the conductivity and redox potential. Additionally, the stabilization of the oxidative species was estimated from the degradation reactions induced by the post-discharge effect, which was significant in the case of N2-NTP, due to the presence of long-lived species, such as nitrite and nitrate. The kinetics study revealed first-order kinetics for IC color removal and the rate constant values followed the order: O2-NTP (3.0 × 10−1 min−1) > O3 (1.4 × 10−1 min−1) > N2-NTP (2.2 × 10−2 min−1) > H2O2 (negligible). Also the main by-products of N2-NTP, O2-NTP and ozonolysis degradation reaction were identified by ultra-fast liquid chromatography coupled with mass spectrometry. The route fragmentation showed the formation of indole intermediates, such as isatin, which is an important precursor in organic synthesis.
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•The species OH.• and NO• formed with the NTP discharge were identified•Degradation rate as follows: O2-NTP > O3 >, N2-NTP > H2O2.•Post-discharge effect was significant for N2-NTP.•IC degradation by-products identified were similar for O2-NTP, O3 and N2-NTP.
We report the first cellular application of the emerging near‐quantitative photoswitch pyrrole hemithioindigo, by rationally designing photopharmaceutical PHTub inhibitors of the cytoskeletal protein ...tubulin. PHTubs allow simultaneous visible‐light imaging and photoswitching in live cells, delivering cell‐precise photomodulation of microtubule dynamics, and photocontrol over cell cycle progression and cell death. This is the first acute use of a hemithioindigo photopharmaceutical for high‐spatiotemporal‐resolution biological control in live cells. It additionally demonstrates the utility of near‐quantitative photoswitches, by enabling a dark‐active design to overcome residual background activity during cellular photopatterning. This work opens up new horizons for high‐precision microtubule research using PHTubs and shows the cellular applicability of pyrrole hemithioindigo as a valuable scaffold for photocontrol of a range of other biological targets.
Pyrrole hemithioindigos can be near‐quantitatively photoisomerised by the laser wavelengths available on confocal microscopes. The first pyrrole hemithioindigo‐based photopharmaceuticals, PHTubs, which are photoswitchable tubulin inhibitors, have been developed. PHTubs optically inhibit microtubule dynamics in live cells with single‐cell, second‐scale spatiotemporal precision, with both lit‐active and dark‐active compounds demonstrated in action.
Druglike small molecules with photoswitchable bioactivity—photopharmaceuticals—allow biologists to perform studies with exquisitely precise and reversible, spatial and temporal control over critical ...biological systems inaccessible to genetic manipulation. The photoresponsive pharmacophores disclosed have been almost exclusively azobenzenes, which has limited the structural and substituent scope of photopharmacology. More detrimentally, for azobenzene reagents, it is not researchers’ needs for adapted experimental tools, but rather protein binding site sterics, that typically force whether the trans (dark) or cis (lit) isomer is the more bioactive. We now present the rational design of HOTubs, the first hemithioindigo‐based pharmacophores enabling photoswitchable control over endogenous biological activity in cellulo. HOTubs optically control microtubule depolymerisation and cell death in unmodified mammalian cells. Notably, we show how the asymmetry of hemithioindigos allows a priori design of either Z‐ or E‐ (dark‐ or lit)‐toxic antimitotics, whereas the corresponding azobenzenes are exclusively lit‐toxic. We thus demonstrate that hemithioindigos enable an important expansion of the substituent and design scope of photopharmacological interventions for biological systems.
Switch me off, switch me on: The first use of the hemithioindigo scaffold as a photoswitchable inhibitor pharmacophore is reported for the preparation of photopharmaceuticals to control endogenous cytoskeleton structure and cell cycle. Hemithioindigos allow a priori design of either Z‐ or E‐ (dark‐ or lit‐) bioactives, so they may address the problem of undesirable dark activity in the chemistry of cellular photopharmaceuticals.
Diagnosing the invasion depth of gastric cancer (GC) is necessary to determine the optimal method of treatment. Although the efficacy of evaluating macroscopic features and EUS has been reported, ...there is a need for more accurate and objective methods. The primary aim of this study was to test the efficacy of novel artificial intelligence (AI) systems in predicting the invasion depth of GC.
A total of 16,557 images from 1084 cases of GC for which endoscopic resection or surgery was performed between January 2013 and June 2019 were extracted. Cases were randomly assigned to training and test datasets at a ratio of 4:1. Through transfer learning leveraging a convolutional neural network architecture, ResNet50, 3 independent AI systems were developed. Each system was trained to predict the invasion depth of GC using conventional white-light imaging (WLI), nonmagnifying narrow-band imaging (NBI), and indigo-carmine dye contrast imaging (Indigo).
The area under the curve of the WLI AI system was .9590. The lesion-based sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the WLI AI system were 84.4%, 99.4%, 94.5%, 98.5%, and 92.9%, respectively. The lesion-based accuracies of the WLI, NBI, and Indigo AI systems were 94.5%, 94.3%, and 95.5%, respectively, with no significant difference.
These new AI systems trained with multiple images from different angles and distances could predict the invasion depth of GC with high accuracy. The lesion-based accuracy of the WLI, NBI, and Indigo AI systems was not significantly different.
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A new approach for removal of indigo carmine blue (IC) dye which is extensively used in jeans manufacture was successfully performed on novel mesoporous LDH nanoparticles prepared by sol-gel route ...using CTAB as shape and pore directing agent. The physicochemical features were monitored by X-ray diffraction (XRD), Fourier transformer infra-red (FTIR), N2 adsorption-desorption isotherm, Field emission electron microscope (FESEM) and high resolution transmission electron microscope (HRTEM). The influence of reaction parameters affecting dye adsorption including contact time, initial dye concentration, pH and temperature were investigated. Textural analysis and HRTEM images indicate the existence of mesoporous spherical nanoparticles of size = 26 nm connected to each other's and embedded large numbers of mesopores of average pore radius = 43.5 Å. A successful adsorption of IC on LDH nanoparticles of surface area = 85.6 m2/g at various pH with maximum adsorption capacity = 62.8 mg/g at pH = 9.5. Langmuir model is more favorable to describe the adsorption of IC rather than Freundlich model which reflecting the preferential formation of monolayer on the surface of LDH. Both film diffusion and the intraparticle diffusion affect the dye adsorption. The values of enthalpy change (ΔH) for and (ΔS) are + 28.18 and + 0.118 kJ/mol, respectively indicating that the removal process is endothermic. The results indicated that LDH nanoparticles conserved a good activity even after five consecutive cycles of reuse. Our results suggest that mesoporous LDH nanoparticles are considered a potential novel adsorbent for remediation of wastewater containing IC.
A successful removal of indigo carmine dye on mesoporous LDH nanoparticles. Display omitted
•A novel mesoporous LDH nanoparticle were prepared by sol-gel route.•CTAB was added to manipulate spherical nanoparticles.•Nanoparticles with various pore dimensions were obtained.•A successful removal of 95% of indigo carmine dye after 30-min is performed.•Regeneration of the solid after five consecutive cycles is performed.
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•For the first time, nine natural deep eutectic solvents were investigated for indigo carmine extraction.•New approach was presented for fast, simple and accurate determination of ...indigo carmine.•Central composite design with desirability function was used for experimental modeling and optimization.•Satisfactory repeatability, high enrichment, low LOD and wide linearity were obtained.
This study report optimization of vortex-assisted natural deep eutectic solvent based liquid-phase microextraction (VA-NADES-LPME) for determination of indigo-carmine in some food samples by UV–Visible spectrophotometer. To ensure efficient extraction, nine different NADES were prepared and tested for the extraction of indigo-carmine. In order to increase extraction efficiency of indigo-carmine, the effects of VA-NADES-LPME variables and their interactions were optimized with central composite design. The optimized method exhibited a linear range between 10 and 900 ng mL−1. Limit of detection, limit of quantification and enrichment factor were determined as 3.3 ng mL−1, 10 ng mL−1 and 135-fold, respectively. The applicability of the optimized method was investigated in selected food samples using the matrix-matching calibration curve. Using optimised experimental conditions (pH of 3.2, 75 µL of NADES-4, 285 µL of THF, and 4 min vortexing), satisfactory recovery results were found in the range of 95.9–104.2% with 1.4–3.7% of relative standard deviation. Finally, the optimized method was economical, simple, green, requires less laborious sampling, and provides superior accuracy and precision in trace-level analysis.
•Indigo carmine is useful to detect urinary tract injuries in benign vaginal surgery.•Indigo carmine could be use alone or in combined with cystoscopy.•Intravenous use of indigo carmine is safe and ...cost-effective.
Unrecognized ureteral and bladder injury increase morbidity and mortality in gynecologic surgery. The primary objective of this study is to analyze the efficiency of a systematic intra-venous (IV) injection of carmine indigo to detect bladder injury in gynecologic vaginal surgery for benign disease. The secondary objective is to analyze the cost and use of carmine indigo.
A retrospective, monocentric study was conducted in a tertiary hospital between January 2018 and October 2021. All patients undergoing a vaginal surgery of hysterectomy for benign disease or anterior prolapse were systematically included. Patients can be systematically included by the automatic coding of surgery. After anesthesia, during the patient's installation, an intravenous injection of 5 mL of intravenous indigo carmine (Carmyne®) diluted in 100 mL of physiological serum was systematically administered by the anesthesia team. Intraoperative cystoscopy was performed only in cases of suspected associated ureteral injury.
We recorded 443 vaginal hysterectomies for benign disease and 95 vaginal anterior prolapse surgeries. There were 6 (1,4%) bladder injuries during vaginal hysterectomies and 1 (1,1%) bladder injury during vaginal prolapse surgery. All bladder injuries were diagnosed intraoperatively. No ureteral injury was diagnosed in this series of patients. No complication related to IV indigo carmine injection was found. In this tertiary hospital, 1085 ampoules of carmine indigo were ordered during the same period, approximatively 270 per year. The total cost to the gynecology and obstetrics department was 19,600 euros, or about 4,900 euros per year. Half of the carmine indigo was used in vaginal surgery and half in laparotomy, caesarean section and endometriosis surgery for suspected bladder or ureteral injury.
Issues surrounding the reversible photocontrol of biological systems by the incorporation of molecular photoswitches are examined. Photoswitches are used for photoregulation of biological processes.
Background and Aim
Chromoendoscopy with the use of indigo carmine (IC) dye is a crucial endoscopic technique to identify gastrointestinal neoplasms. However, its performance is limited by the ...endoscopist's skill, and no standards are available for lesion identification. Thus, we developed an artificial intelligence (AI) model to replace chromoendoscopy.
Methods
This pilot study assessed the feasibility of our novel AI model in the conversion of white‐light images (WLI) into virtual IC‐dyed images based on a generative adversarial network. The predictions of our AI model were evaluated against the assessments of five endoscopic experts who were blinded to the purpose of this study with a staining quality rating from 1 (unacceptable) to 4 (excellent).
Results
The AI model successfully transformed the WLI of polyps with different morphologies and different types of lesions in the gastrointestinal tract into virtual IC‐dyed images. The quality ratings of the real IC‐dyed and AI images did not significantly differ concerning surface structure (AI vs IC: 3.08 vs 3.00), lesion border (3.04 vs 2.98), and overall contrast (3.14 vs 3.02) from 10 sets of images (10 AI images and 10 real IC‐dyed images). Although the score depended significantly on the evaluator, the staining methods (AI or real IC) and evaluators had no significant interaction (P > 0.05) with each other.
Conclusion
Our results demonstrated the feasibility of employing AI model's virtual IC staining, increasing the possibility of being employed in daily practice. This novel technology may facilitate gastrointestinal lesion identification in the future.
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