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Designing novel functional compounds is a key step in coordination and organic materials chemistry. Herein, 9-phenanthrenylvinyl-4′-pyridine (9-PheVP), as a new ligand, has been synthesized and structurally characterized for the first time, along with its N-methylated analogue (9-MPheVP). Both compounds have been explored for their photophysical and redox properties and their applicability in bioimaging. The effect of quaternization on the crystal structure, absorption, emission, and redox properties has been investigated. Bathochromic and hypochromic shifts were observed in the absorption and emission properties upon quaternization. Both neutral and cationic compounds showed large Stokes shifts of 9250 and 8000 cm–1, respectively. 9-MPheVPwas observed to photoisomerize in the solid state to its cis-configuration (9-MPheVP-cis) upon exposure to light. Crystal structure determination of 9-MPheVP-cisrevealed that with Z′ = 2, it represents a rare class of crystals for which Z′> 1. The utility of 9-MPheVPas an efficient ligand has also been established by structurally characterizing a silver(I) complex, [Ag(9-PheVP)2]BF4. Our results show that 9-PheVPcan serve as a promising ligand in coordination chemistry and offers a platform for developing multifunctional organic materials.

In the pathogenesis of microglia, brain immune cells promote nitrergic stress by overproducing nitric oxide (NO), leading to neuroinflammation. Furthermore, NO has been linked to COVID-19 progression, which has caused significant morbidity and mortality. SARS-CoV-2 infection activates inflammation by releasing excess NO and causing cell death in human microglial clone 3 (HMC3). In addition, NO regulates lysosomal functions and complex machinery to neutralize pathogens through phagocytosis. Therefore, developing lysosome-specific NO probes to monitor phagocytosis in microglia during the COVID-19 infection would be a significant study. Herein, a unique synthetic strategy was adopted to develop a NO selective fluorescent probe, PDM-NO, which can discriminate activated microglia from their resting state. The nonfluorescent PDM-NOexhibits a turn-on response toward NO only at lysosomal pH (4.5–5.5). Quantum chemical calculations (DFT/TD-DFT/PCM) and photophysical study revealed that the photoinduced electron transfer (PET) process is pivotal in tuning optical properties. PDM-NOdemonstrated good biocompatibility and lysosomal specificity in activated HMC3 cells. Moreover, it can effectively map the dynamics of lysosomal NO against SARS-CoV-2 RNA-induced neuroinflammation in HMC3. Thus, PDM-NOis a potential fluorescent marker for detecting RNA virus infection and monitoring phagocytosis in HMC3.

ABSTRACTIn this article, an incisive analysis had been carried out to investigate the impact of air pollution on groundwater through a water reservoir. The primary objective of the present work was to develop a mathematical model that shows the direct impact of air pollution on groundwater contamination. The advection-dispersion equation (ADE) was considered to model the contaminant transport through the different media. Due to its inherent complexities, contaminant transport through the different domains was often difficult to model. To overcome it, the simple solution was to consider different velocities and dispersion for different domains. It was considered that the air zone was directly connected with the groundwater through a large water body. Initially, water body and aquifer had been considered contaminant free along with the flux type boundary condition at the semi-infinite part of the boundary. The model had been solved analytically using Laplace transformations. The current study demonstrates that depending upon the length of the medium the impact of contaminant would vary significantly. The air pollution source height had a direct impact on the contaminant concentration level in the aquifer aquitard system. The current study also illustrates that around 25% of air pollutants were induced in the groundwater.

Mitochondrial functions are heavily influenced by acid–base homeostasis. Hence, elucidation of the mitochondrial pH is essential in living cells, and its alterations during pathologies is an interesting question to be addressed. Small molecular fluorescent probes are progressively applied to quantify the mitochondrial pH by fluorescence imaging. Herein, we designed a unique small molecular fluorescent probe, PM-Mor-OH, based on the lipophilic morpholine ligand-conjugated pyridinium derivative of “IndiFluors”. The morpholine-conjugated fluorescent probe usually localized the lysosome. However, herein, we observed unusual phenomena of morpholine-tagged PM-Mor-OHthat localized mitochondria explicitly. The morpholine ligand also plays a pivotal role in tuning optical properties via photoinduced electron transfer (PET) during internal pH alteration (ΔpHi). In the mitophagy process, lysosomes engulf damaged mitochondria, leading to ΔpHi, which can be monitored using our probe. It exhibited “ratiometric” emission at single wavelength excitation (ex. 488) and is suitable for monitoring and quantifying the ΔpHi using confocal microscope high-resolution image analysis during mitophagy. The bathochromic emission shifts due to intramolecular charge transfer (ICT) in basic pH were well explained by the time-dependent density functional theory (TD-DFT/PCM). Similarly, the change in the emission ratio (green/red) with pH variations was also validated by the PET process. In addition, PM-Mor-OHcan quantify the pH change during oxidative stress induced by rapamycin, mutant A53T α-synuclein-mediated protein misfolding stress in mitochondria, and during starvation. Rapamycin-induced mitophagy was further elucidated by the translocation of mCherry Parkin to damaged mitochondria, which well correlates with our probe. Thus, PM-Mito-OHis a valuable probe for visualizing mitophagy and can act as a suitable tool for the diagnosis of mitochondrial diseases.

Tumor initiating cells (TIC) are resistant to conventional anticancer therapy and associated with metastasis and relapse in cancer. Although various TIC markers and their antibodies have been proposed, it is limited to the use of antibodies for in vivo imaging or treatment of TIC. In this study, we discovered heme oxygenase 2 (HMOX2) as a novel biomarker for TIC and developed a selective small molecule probe TiNIR (tumor initiating cell probe with near infrared). TiNIR detects and enriches the functionally active TIC in human lung tumors, and through the photoacoustic property, TiNIR also visualizes lung TIC in the patient-derived xenograft (PDX) model. Furthermore, we demonstrate that TiNIR inhibits tumor growth by blocking the function of HMOX2, resulting in significantly increased survival rates of the cancer model mice. The novel therapeutic target HMOX2 and its fluorescent ligand TiNIR will open a new path for the molecular level of lung TIC diagnosis and treatment.

Chronic kidney disease (CKD) is rapidly heading towards epidemic proportion globally, requires dialysis or kidney transplantation. No generally applicable therapies to slow progression of renal disease are available. The aim of this study was to evaluate Lactobacillus plantarumAD3 as an effective probiotic strain for acetaminophen induced uremic patient.

Crystal packing-dependent photochemical reactions of several functional olefins have been explored, but not for 1-naphthylvinyl-4-quinoline (NVQ) and analogous N-methylated 1-naphthylvinyl-4-quinoline cation (MNVQ). Herein, crystal structure elucidation and photophysical and electrochemical properties for both NVQand MNVQ, and photodimerization reaction with a photosalient effect for MNVQhave been investigated for the first time. The neutral compound NVQstacks parallel in its crystal; however, having a distance of 4.43 Å between the C═C bonds, it remained photoinert. Upon methylation at the quinoline-N, the resulting MNVQcations stack parallel in a head-to-tailfashion with a distance of 3.6 Å between the C═C bonds, and consequently it underwent [2 + 2] photocycloaddition reaction quantitatively to MQNCBdication, when irradiated under visible light (∼410 nm). Monitoring closely the single crystals of MNVQunder blue light showed that they burst upon exposure for 1 min, signifying a photosalient behavior. Measurements of photophysical properties showed that MNVQexhibited a bathochromic shift in both absorption (by 4772 cm–1) and emission (by 6198 cm–1) compared to the neutral NVQ. Upon photodimerization, the MQNCBdication exhibited a hypsochromic and hypochromic shift both in absorption and emission compared to the MNVQcation, a signature of cessation of conjugation. Cyclic voltammetry (CV) measurements showed that all three compounds are redox active and exhibit a reversible reduction event in the range of −0.6 to −0.9 V (vs Ag/AgCl). Experimental results have been substantiated by theoretical calculations.

The differentiation of the distinct phenotypes of macrophages is essential for monitoring the stage of inflammatory diseases for accurate diagnosis and treatment. Recent studies revealed that the level of hypochlorite (OCl–) varies from activated M1 macrophages (killing pathogens) to M2 (resolution of inflammation) during inflammation. Thus, we developed a simple and efficient fluorescent probe for discriminating M1 from M0 and M2. Herein, fluorescent-based imaging is applied as an alternative to immunohistochemistry, which is challenging due to the tedious process and high cost. We developed a hypochlorite-specific probe PMS-Tto differentiate M1 and M2, employing a metabolism-oriented live-cell distinction. This probe enables the detection of inflammatory rheumatoid arthritis in an ex vivomouse model. Thus, it can be a potential chemical tool for monitoring inflammatory diseases, including rheumatoid arthritis, that may overcome the existing barriers of immunohistochemistry.

Zuverlässige Berichterstattung: Das Screening einer 80‐teiligen Tricarbocyanin‐Bibliothek lieferte CyNAMLA‐381 als Nahinfrarot‐SERS‐Reporter mit guter Signalstabilität und höherer Empfindlichkeit als der Standard (SERS=oberflächenverstärkte Raman‐Spektroskopie). Durch Verkapselung von CyNAMLA‐381 an der Oberfläche von Gold‐Nanopartikeln und Konjugation mit Antikörpern wurden SERS‐Nanomarker mit ausgezeichneter Empfindlichkeit, Stabilität und Tumorspezifität in Xenograft‐Modellen erhalten (siehe Bild).

Of good report: Synthesis and screening of an 80‐member tricarbocyanine library identified CyNAMLA‐381 as a near‐IR surface‐enhanced Raman spectroscopy (SERS) reporter with good signal stability and higher sensitivity than the standard. Encapsulation of CyNAMLA‐381 on gold nanoparticles and conjugation to an antibody afforded SERS nanotags with excellent sensitivity, stability, and tumor specificity in xenograft models (see picture).

A NIR death experience: A highly photostable NIR protein‐labeling dye (CyNE790) that maintained excellent fluorescent properties after protein conjugation has been synthesized. Furthermore, the adequacy of the dye for NIR imaging was confirmed by showing that the recognition properties of a labeled anti‐EGFR antibody remained unaffected.

In article number 1700870, Yoon‐Sik Lee and co‐workers demonstrate in vivo validation process of candidate antibodies against human colon cancer, using a ratiometric quantification method. The validation is performed on a single mouse and analyzed by multiplexed surface‐enhanced resonance Raman scattering (SERRS) with ultrasensitive and near‐infrared (NIR)‐active SERRS nanoprobes (NIR‐SERRS dots).

Immunotargeting ability of antibodies may show significant difference between in vitro and in vivo. To select antibody leads with high affinity and specificity, it is necessary to perform in vivo validation of antibody candidates following in vitro antibody screening. Herein, a robust in vivo validation of anti‐tetraspanin‐8 antibody candidates against human colon cancer using ratiometric quantification method is reported. The validation is performed on a single mouse and analyzed by multiplexed surface‐enhanced Raman scattering using ultrasensitive and near infrared (NIR)‐active surface‐enhanced resonance Raman scattering nanoprobes (NIR‐SERRS dots). The NIR‐SERRS dots are composed of NIR‐active labels and Au/Ag hollow‐shell assembled silica nanospheres. A 93% of NIR‐SERRS dots is detectable at a single‐particle level and signal intensity is 100‐fold stronger than that from nonresonant molecule‐labeled spherical Au NPs (80 nm). The result of SERRS‐based antibody validation is comparable to that of the conventional method using single‐photon‐emission computed tomography. The NIR‐SERRS‐based strategy is an alternate validation method which provides cost‐effective and accurate multiplexing measurements for antibody‐based drug development. In vivo validation of antibody leads against human colon canceris demonstrated in a single animal by ratiometric quantitative and multiplexed analysis with ultrasensitive and near‐infrared‐active surface‐enhanced resonance Raman scattering probes.

rational design of an amine tricarbocyanine structure with improved photostability and its combinatorial derivatization to render CyNA‐414 (I) as a near‐infrared fluorescent dye with stronger emission intensity and higher photostability than NIR standard IndoCyanine Green