Water striders are impervious to raindrop collision forces and submerged by collapsing craters.

Water striders are abundant in areas with high humidity and rainfall. Raindrops can weigh more than 40 times the adult water strider and some pelagic species spend their entire lives at sea, never contacting ground. Until now, researchers have not systematically investigated the survival of water striders when impacted by raindrops. In this experimental study, we use high-speed videography to film drop impacts on water striders. Drops force the insects subsurface upon direct contact. As the ensuing crater rebounds upward, the water strider is propelled airborne by a Worthington jet, herein called the first jet. We show the water strider's locomotive responses, low density, resistance to wetting when briefly submerged, and ability to regain a super-surface rest state, rendering it impervious to the initial impact. When pulled subsurface during a second crater formation caused by the collapsing first jet, water striders face the possibility of ejection above the surface or submersion below the surface, a fate determined by their position in the second crater. We identify a critical crater collapse acceleration threshold ∼ 5.7 gravities for the collapsing second crater which determines the ejection and submersion of passive water striders. Entrapment by submersion makes the water strider poised to penetrate the air-water interface from below, which appears impossible without the aid of a plastron and proper locomotive techniques. Our study is likely the first to consider second crater dynamics and our results translate to the submersion dynamics of other passively floating particles such as millimetric microplastics atop the world's oceans.

Development of Postanesthesia Care Unit Delirium Is Associated with Differences in Aperiodic and Periodic Alpha Parameters of the Electroencephalogram during Emergence from General Anesthesia: Results from a Prospective Observational Cohort Study.

BACKGROUND: Intraoperative alpha-band power in frontal electrodes may provide helpful information about the balance of hypnosis and analgesia and has been associated with reduced occurrence of delirium in the postanesthesia care unit. Recent studies suggest that narrow-band power computations from neural power spectra can benefit from separating periodic and aperiodic components of the electroencephalogram. This study investigates whether such techniques are more useful in separating patients with and without delirium in the postanesthesia care unit at the group level as opposed to conventional power spectra. METHODS: Intraoperative electroencephalography recordings of 32 patients who developed perioperative neurocognitive disorders and 137 patients who did not were considered in this post hoc secondary analysis. The power spectra were calculated using conventional methods and the "fitting oscillations and one over f" algorithm was applied to separate aperiodic and periodic components to see whether the electroencephalography signature is different between groups. RESULTS: At the group level, patients who did not develop perioperative neurocognitive disorders presented with significantly higher alpha-band power and a broadband increase in power, allowing a "fair" separation based on conventional power spectra. Within the first third of emergence, the difference in median absolute alpha-band power amounted to 8.53 decibels (area under the receiver operator characteristics curve, 0.74 [0.65; 0.82]), reaching its highest value. In relative terms, the best separation was achieved in the second third of emergence, with a difference in medians of 7.71% (area under the receiver operator characteristics curve, 0.70 [0.61; 0.79]). The area under the receiver operator characteristics curve values were generally lower toward the end of emergence with increasing arousal. CONCLUSIONS: Increased alpha-band power during emergence in patients who did not develop perioperative neurocognitive disorders can be traced back to an increase in oscillatory alpha activity and an overall increase in aperiodic broadband power. Although the differences between patients with and without perioperative neurocognitive disorders can be detected relying on traditional methods, the separation of the signal allows a more detailed analysis. This may enable clinicians to detect patients at risk for developing perioperative neurocognitive disorders in the postanesthesia care unit early in the emergence phase.

Investigation of the combined cytotoxicity induced by sodium butyrate and a flavonoid quercetin treatment on MCF-7 breast cancer cells.

Quercetin (QUE) belonging to the flavonoid class is a common phytochemical present in the daily diet of some individuals. Quercetin is an important source of free radical scavengers. This property makes this flavonoid a reliable antioxidant with the following properties: anti-inflammatory, anti-diabetic, antimicrobial and anti-carcinogenic. Sodium butyrate (NaBu) acts as a histone deacetylase inhibitor (HDACi) and is known to regulate apoptosis in cancer cells. Combining natural flavonoids such as QUE with different substances may synergistically enhance their anti-carcinogenic capacity. Thus, the aim of this study was to examine the combined treatment effects of QUE and NaBu in hormone-sensitive breast cancer cells in vitro. MCF-7 breast cancer cells were treated with QUE alone, NaBu alone, as well as QUE and NaBu combined to determine the following: cell proliferation, levels of protein annexin A5 (ANXA5) and reactive oxygen species (ROS), mRNA protein expression, as well as cell and nuclear morphology. Data demonstrated that either QUE or NaBu alone inhibited cell proliferation, and reduced levels protein ANXA5, ROS and mRNA protein expression, The combination of QUE and NaBu produced a significant synergistic inhibitory effect compared to treatment groups of QUE or NaBu alone. In conclusion, our findings showed that the combination treatment of QUE and NaBu may constitute a promising therapeutic approach to breast cancer treatment but this needs further molecular and in vivo investigations.

A cyanobiphenyl-based fluorescent ''lighting-up'' sensor for highly selective and sensitive recognition of Al3+: Theoretical, practical and bioimaging studies.

The recognition of toxic Al3+ in foods and biosystems has of great interest to researchers. Herein, a novel cyanobiphenyl-based chemosensor CATH (E)-N'-((4'-cyano-4-hydroxy-[1,1'-biphenyl]-3-yl)methylene)thiophene-2-carbohydrazide was fabricated and shown to recognize Al3+ in HEPES buffer:EtOH (90:10, v:v, pH = 7.4) by ''lighting-up'' fluorescence sensing. The CATH evidenced high sensitivity (LOD = 13.1 nM) and excellent selectivity to Al3+ over competing cations. The Job's plot, TOF-MS and theoretical computation studies were performed to probe the binding mechanism of Al3+ to CATH. Additionally; CATH was successfully utilized to practical applications and employed to recover of Al3+ from different food samples. More importantly, it was employed to intracellular Al3+ detection in living cells including THLE2 and HepG2.

The effect of quercetin on absence epilepsy in WAG/Rij rats.

AIM: In the present study, the effect of quercetin, a powerful antioxidant flavonoid, on genetic absence epilepsy was studied in WAG/Rij rats. MATERIAL AND METHOD: Tripolar electrodes were implanted into WAG/Rij rats. Basal electrocorticography (ECoG) was recorded following a recovery period. After basal ECoG recording, different doses of quercetin (QRC) (25, 50 and 100 mg/kg) were injected intraperitoneally (i.p.) for 30 days. ECoG recording was continued for 31 days, three hours a day. After recording, the rats were anesthetized and euthanized through cervical dislocation and their brains were excised. Biochemically, TNF-alpha, IL-6 and NO were studied in whole rat brains. RESULTS: In WAG/Rij rats, low-dose quercetin (25 mg/kg) reduced the number and duration of spike-wave discharges (SWDs) compared to the control group. However, 50 and 100 mg/kg quercetin doses increased SWDs. Duration of SWDs was prolonged only with 100 mg/kg dose. None of the quercetin doses had any effect on average amplitude of SWDs. In addition, it was observed in biochemical analyses that 25 mg/kg quercetin reduced TNF-alpha, IL-6 and NO levels compared to the control group. While TNF-alpha and IL-6 levels in rat brains were not affected by 50 or 100 mg/kg doses, both doses were found to increase NO levels in rat brains. CONCLUSION: Based on the results of the present study, 25 mg/kg low-dose quercetin may have reduced absence seizures by reducing proinflammatory cytokines and NO, but high-dose quercetin may have increased absence seizures through increasing the NO level. This contrasting effect of quercetin on absence seizures needs to be investigated by advanced mechanisms.

"Lighting up" fluorescence precise recognition of Al3+ with an effective fluorescence detection using a Bisphenol A-based sensor.

Although aluminum is a ubiquitous metal in the ecosystem and has numerous critical roles in both the medicinal and biological fields, human daily life is seriously threatened by its assorted harmful influences. By this virtue, tracking the amount of aluminum byrapid sensitive and selective recognition methodologies is of great importance. Based on this, a novel fluorescent chemosensor 4,4'-(propane-2,2-diyl)bis(2-(((-2-hydroxybenzylidene) hydrazineylidene)-methyl)phenol) (BFASA) capable of recognizing Al3+ in a medium was constructed via an easy Schiff-base reaction between bisphenol A-containing molecule and the salicylaldehyde. The metal-binding studies of BFASA indicated a drastically enhanced emission with color alteration from colorless to green establishing the utility of BFASA against monitoring of Al3+ and only Cu2+/Al3+ significantly enhanced the absorbance intensity of the probe solution at 433 and 406, respectively. Its ability to selectively sense Al3+ demonstrated "switch-on" fluorescence responses for Al3+ with a low detection limit (LOD) of 0.56 µM and good selectivity, and pH adaptation range (5-8). The stoichiometric ratio of BFASA against the Al3+ was verified by the Job's plot and TOF-MS analysis and determined as 1:2. To make the recognition process inexpensively, viable and straightforward, Smartphone application of BFASA was effectively applied to Al3+ sensing, which could benefit the on-site Al3+ recognition. In the fluorescence bio-imaging aspect, the BFASA could effectively monitor Al3+ in living cells.

The role of next-generation sequencing in the examination of signaling genes in Brca1/2-negative breast cancer cases.

INTRODUCTION: Breast cancer is the most prevalent malignancy in women worldwide. Although pathogenic variants in the BRCA1/2 genes are responsible for the majority of hereditary breast cancer cases, a substantial proportion of patients are negative for pathogenic variations in these genes. In cancers, the signal transduction pathways of the cell are usually affected first. Therefore, this study aimed to detect and classified genetic variations in non-BRCA signaling genes and investigate the underlying genetic causes of susceptibility to breast cancer. METHODS: Ninety-six patients without pathogenic variants in the BRCA1/2 genes who met the inclusion criteria were enrolled in the study, and 34 genes were analyzed using next-generation sequencing (NGS) for genetic analysis. RESULTS: Based on the ClinVar database or American College of Medical Genetics criteria, a total of 55 variants of 16 genes were detected in 43 (44.8%) of the 96 patients included in the study. The pathogenic variants were found in the TP53, CHEK2, and RET genes, whereas the likely pathogenic variants were found in the FGFR1, FGFR3, EGFR, and NOTCH1 genes. CONCLUSION: The examination of signaling genes in patients who met the established criteria for hereditary breast cancer but were negative for BRCA1/2 pathogenic variants provided additional information for approximately 8% of the families. The results of the present study suggest that NGS is a powerful tool for investigating the underlying genetic causes of occurrence and progression of breast cancer.

Ultrasensitive detection of Cu2+: A cyanobiphenyl-based colorimetric and fluorescence chemosensor and its Smartphone and food sample applications.

A new cyanobiphenyl-based compound 4-hydroxy-3-(((4-(phenylamino)phenyl)imino)methyl)-[1,1-biphenyl]-4-carbonitrile (PEBP) for Cu2+ detection was fabricated and successfully characterized. PEBP was employed as a sensor for Cu2+ sensing and used as an extremely fast responsive colorimetric and ''ON/OFF'' fluorescent sensor in H2O:CH3CN (40:60, v/v). Highly selective fluorescence response of PEBP to Cu2+ yielded an excellently low detection limit of 20.4 nM. Binding stoichiometry for PEBP-Cu2+ was found to be 2:1 by Job's plot study, as well MALDI TOF-MS data, and the binding constant was computed as 0.62 × 102 M-1/2. The validation study was employed using analytical parameters and statistical tests. To understand the binding capability, density functional theory (DFT) study was performed. Smartphone and applications for different food and drinking water samples were successfully constructed for Cu2+ detection, and the findings revealed that PEBP could be easily employed for in-site Cu2+detection without sophisticated instrument.

A novel ratiometric fluorescent and colorimetric sensor based on a 1,8-naphthalimide derivative for nanomolar Cu2+ sensing: smartphone and food applications.

A novel 1,8-naphthalimide-based chemical sensor 3-((2-(2-butyl-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinoline-6-yl)hydrazone-o)methyl)-4-hydroxy-[1,1-biphenyl]-4-carbonitrile (BUDIN) with ratiometric fluorescence behavior, as well as "naked-eye" response was developed for the sensitive and specific determination of Cu2+ at nanomolar levels. With the addition of different amounts of Cu2+, the emission of BUDIN varied continually, leading to colour changes from yellow to blue (λem = 532 nm to 462 nm) due to intra-ligand charge transfer (ILCT) and metal-ligand charge transfer (MCLT). BUDIN can detect Cu2+ quantitatively with a detection limit of 17 nM. Job's plot, MALDI TOF MS and TOF MS findings revealed that the binding stoichiometry of BUDIN and Cu2+ was 2 : 1. Furthermore, the theoretical computation data strongly supported the optical response of BUDIN toward Cu2+. Smartphone digital imaging studies proved that BUDIN can be utilized as an outstanding chemical sensor for the on-site detection of Cu2+ without the need for sophisticated equipment, with a detection limit of 17.8 µM. The findings also presented that BUDIN is a very effective chemosensor for Cu2+ in real food samples with quite a simple operation.

The diagnostic importance of pathogenic variants and variant coexistence determined by NGS-based liquid biopsy approach in patients with lung adenocarcinoma.

BACKROUND: Identification of driver mutations and rapid detection of genetic changes in lung cancer are critical in the management of the disease. Genetic structures of tumor tissues tend to change constantly and the possibility of emergence of new pathogenic variants that will create resistance to treatment. Liquid biopsy analysis has been one of the most effective approaches used to monitor and identify individual genetic changes. METHODS: In this study, TP53, EGFR, MET, ALK, PIK3CA, MAP2K, ERBB2 and ROS genes in cf DNA samples of 324 patients with lung adenocarcinoma were screened for genetic variations by NGS method. Analysis of the data showed that there were a total of 755 variations in 324 patients. RESULTS: Pathogenic and possibly pathogenic variations were identified in 178 patients (54.9%) on TP53, 118 (36.4%) on EGFR, 55 (17.0%) on MET, 46 (14.2%) on ALK, 39 (12.0%) on MAP2K, 6 (1.9%) on ERBB2 and in 2 (0,6%) patients ROS genes. The detailed variant data of the genes included in the study were compared with the patients' stage status, metastasis status, smoking, age distribution and life span data, and the presence of possible significant relationships and candidate biomarkers for the molecular pathogenesis of the disease were investigated. CONCLUSION: As a result of data analysis, genetic changes associated with metastasis and adenocarcinoma formation were identified. It has been shown that variations identified in TP53, PIK3CA, MAP2K1 and EGFR genes can play critical roles in the pathogenesis and development of the disease.

Redox-Responsive Hydrogels for Tunable and "On-Demand" Release of Biomacromolecules.

In recent years, stimuli-responsive degradation has emerged as a desirable design criterion for functional hydrogels to tune the release of encapsulated payload as well as ensure degradation of the gel upon completion of its function. Herein, redox-responsive hydrogels with a well-defined network structure were obtained using a highly efficient thiol-disulfide exchange reaction. In particular, gelation occurred upon combining thiol-terminated tetra-arm polyethylene glycol (PEG) polymers with linear telechelic PEG-based polymers containing pyridyl disulfide units at their chain ends. Rapid gelation proceeds with good conversions (>85%) to yield macroporous hydrogels possessing high water uptake. Furthermore, due to the presence of the disulfide linkages, the thus-obtained hydrogels can self-heal. The obtained hydrogels undergo complete degradation when exposed to environments rich in thiol-containing agents such as dithiothreitol (DTT) and L-glutathione (GSH). Also, the release profile of encapsulated protein, namely, bovine serum albumin, can be tuned by varying the molecular weight of the polymeric precursors. Additionally, it was demonstrated that complete dissolution of the hydrogel to rapidly release the encapsulated protein occurs upon treating these hydrogels with DTT. Cytotoxicity evaluation of the hydrogels and their degradation products indicated the benign nature of these hydrogels. Additionally, the cytocompatible nature of these materials was also evident from a live/dead cell viability assay. One can envision that the facile fabrication and their ability to degrade on-demand and release their payload will make these benign polymeric scaffolds attractive for various biomedical applications.

Lessening the toxic effect of the methylisothiazolinone via vermicompost tea on Pisum sativum.

Biocides, which are found in nature as persistent pollutants, pose a great danger to the ecosystem. Methylisothiazolinone (MIT), a widely used biocide, reaches plants by mixing with water and soil. Vermicompost tea (VCT), which strengthens the plant defence mechanism and increases its growth and development, is a liquid fertiliser consisting of the cooperation of worms with microbes. In the present study, after applying 0.4 g/L (EC50/2), 0.8 g/L (EC50), and 1.6 g/L (EC50 × 2) MIT concentrations without and with VCT on forage pea (Pisum sativum), root lengths, mitotic index data, chromosome and nuclei abnormalities, and DNA damage level were determined. When VCT applied and non-applied groups were compared, it was found that, especially in the VCT applied group, they cope with the stress conditions created by MIT. In addition, positive effects were observed in root lengths, mitotic index data, and amount of cell nuclei abnormalities. In line with other study results, VCT reduces cellular damage by regulating the normal life cycle disrupted in the cell due to mutagens using the curative-regulatory feature.

Evaluation of the antioxidative and genotoxic effects of sodium butyrate on breast cancer cells.

Oncogenic stimulation shows a rise in reactive oxygen species (ROS), and ROS can eventually induce carcinogenesis by causing DNA damage. In this context, this study aims to evaluate some biochemical and genotoxic changes in the control of cell death caused by NaBu (Sodium butyrate). treatment in breast cancer cells. NaBu's impact on cell proliferation was determined via WST-1 assay. The lipid peroxidation (MDA), reduced glutathione (GSH), Nitric Oxide (NO), hydrogen peroxide (H2O2), and superoxide dismutase (SOD) enzyme levels were determined biochemically. NaBu-induced genotoxic damage was estimated via single-cell gel electrophoresis (SCGE). NaBu reduced cell viability and potentially induced GSH, but decreased SOD enzyme activity and the level of MDA and NO decreased also H2O2 decreased at different times and NaBu concentrations. Higher NaBu concentrations amplified DNA damage in MCF-7 cells compared to the control group. NaBu shows anticancer and genotoxic effects, especially through antioxidant enzymes, one of the oxidative stress parameters in breast cancer. However, the anticancer and genotoxic effects of NaBu is changed in the oxidative stress parameters with time and treatment concentration of NaBu in MCF-7 cells. Furthermore, his oxidative stress-dependent effect changes need to be clarified by further evaluation with molecular and more biochemical parameters.

Phenolphthalein Conjugated Schiff Base as a Dual Emissive Fluorogenic Probe for the Recognition Aluminum (III) and Zinc (II) Ions.

In this study, a new phenolphthalein derivative, FFIZNA, has been planned and successfully prepared in an uncomplicated way. The probe FFIZNA could selectively monitor Al3+ and Zn2+ among other relevant cations with diverse colors through a turn-on emission response in EtOH:HEPES (9/1;v/v) media owing to the chelation enhanced fluorescence (CHEF), prevention of ESIPT, -C=N- isomerization and PET of the probe FFIZNA. The interactions of Al3+ and Zn2+ with the probe FFIZNA were confirmed by emission spectroscopy, Job's plot and 1H-NMR titration substantiated 1:2 reaction stoichiometry between FFIZNA and Al3+ and Zn2+. The time-response study displayed that the emission of FFIZNA with Al3+ and Zn2+, rapidly boosted and reached the stable value in less than 3.0 and 4.0 min, respectively. Therefore, the FFIZNA has successfully been utilized to the dual recognition of Al3+ and Zn2+ in solutions. Phenolphthalein conjugated schiff base as a dual emissive fluorogenic probe for the detection aluminum (III) and zinc (II) ions.

Fabrication and sensing properties of phenolphthalein based colorimetric and turn-on fluorogenic probe for CO32- detection and its living-cell imaging application.

Herein, an easy assembled colorimetric and ''turn-on'' fluorescent sensor (probe P4SC) based on phenolphthalein was developed for carbonate ion (CO32-) sensing in a mixture of EtOH/H2O (v/v, 80/20, pH = 7, Britton-Robinson buffer) media. The probe P4SC demonstrated high sensitive and selective monitoring toward CO32- over other competitive anions. Interaction of CO32- with the probe P4SC resulted in a significant increment in emission intensity at λem = 498 nm (λex = 384 nm) due to the strategy of blocking the photo induced electron transfer (PET) mechanism. 1H NMR titration and Job's methods, as well as the theoretical study were carried out to support the probable stoichiometry of the reaction (1:2) between P4SC and CO32-. The binding constant of the probe P4SC with CO32- was calculated as 2.56 × 1010 M-2. The probe P4SC providing rapid response time (~0.5 min) with a satisfactorily low detection limit (14.7 nM) may be useful as a valuable realistic sensor. The imaging studies on the liver cancer cells (HepG2) shows the great potential of the probe P4SC for the sensation of intracellular CO32- anions. Furthermore, the satisfactory recovery and RSD values obtained for water application confirming that the probe P4SC could be applied to sensing of CO32- ion.

A novel phenolphthalein-based fluorescent sensor for Al3+ sensing in drinking water and herbal tea samples.

In this study, 3,3-bis(4-hydroxy-3-((E)-((4-hydroxyphenyl)imino)methyl) phenyl)isobenzofuran-1(3H)-one (HMBP) was designed as a ''turn-on″ fluorogenic chemosensor to detect Al3+. Studies were performed in C2H5OH-HEPES (v/v, 9/1, pH 7.0) media at λem = 475 nm. The LOD value was found to be 0.113 µM. The stoichiometric ratio of HMBP-Al3+ was determined as 1:2 by Job's plot and ESI-MS as well as 1H NMR titration. The binding constant of chemosensor HMBP with Al3+ from the Benesi-Hildebrand equation was determined to be 1.21 × 108 M-1. The quantum (Φ) yields were obtained as 0.040 and 0.775 for the chemosensor HMBP and HMBP-Al3+, respectively. The response of the chemosensor HMBP towards Al3+ was attributed to the strategies of blocking the photo-induced electron transfer (PET) and CN isomerisation mechanisms. Finally, the sensing of the chemosensor HMBP for the determination of Al3+ in real food samples, drinking waters and herbal teas, were employed.

Photothermally Active Cryogel Devices for Effective Release of Antimicrobial Peptides: On-Demand Treatment of Infections.

There has been significant interest in the use of peptides as antimicrobial agents, and peptide containing hydrogels have been proposed as biological scaffolds for various applications. Limited stability and rapid clearance of small molecular weight peptides pose challenges to their widespread implementation. As a common approach, antibacterial peptides are physically loaded into hydrogel scaffolds, which leads to continuous release through the passive mode with spatial control but provides limited control over drug dosage. Although utilization of peptide covalent linkage onto hydrogels addresses partially this problem, the peptide release is commonly too slow. To alleviate these challenges, in this work, maleimide-modified antimicrobial peptides are covalently conjugated onto furan-based cryogel (CG) scaffolds via the Diels-Alder cycloaddition at room temperature. The furan group offers a handle for specific loading of the peptides, thus minimizing passive and burst drug release. The porous nature of the CG matrix provides rapid loading and release of therapeutic peptides, apart from high water uptake. Interfacing the peptide adduct containing a CG matrix with a reduced graphene oxide-modified Kapton substrate allows "on-demand" photothermal heating upon near-infrared (NIR) irradiation. A fabricated photothermal device enables tunable and efficient peptide release through NIR exposure to kill bacteria. Apart from spatial confinement offered by this CG-based bandage, the selective ablation of planktonic Staphylococcus aureus is demonstrated. It can be envisioned that this modular "on-demand" peptide-releasing device can be also employed for other topical applications by appropriate choice of therapeutic peptides.

An 'on-demand' photothermal antibiotic release cryogel patch: evaluation of efficacy on an ex vivo model for skin wound infection.

A myriad of topical therapies and dressings are available to the clinicians for wound healing skin, but only a very few have shown their effectiveness in promoting wound repair due to challenges in controlling drug release. To address this issue, in this work, a near infrared (NIR)-light activable cryogel based on butyl methacrylate (BuMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) incorporated with reduced graphene oxide (rGO) was fabricated. The obtained cryogel provides the required hydrophilicity beneficial for wound treatment. The excellent photo-thermal properties of rGO allow for heating the cryogel, which results in subsequent swelling of the cryogel (CG) followed by release of the encapsulated drug load, cefepime in our case. Without photothermal activation, no release of payload was observed. The potential of this bandage for wound healing was examined using an ex vivo human skin model infected with Staphylococcus aureus (S. aureus). Apart from the efficacy of the cryogel based wound healing system, our results also suggest that the ex vivo wound model evaluated here provides a rapid and valuable tool to study superficial skin infections in humans and test the efficacy of antimicrobial agents.

Thiazolidine based fluorescent chemosensors for aluminum ions and their applications in biological imaging.

Utilization of fluorescent techniques in detection of various metal ions actively pursued allow ultrasensitive and selective detections of metal ions and prevent the adverse effect of cations such as aluminum (III) ions. In this study, two novel fluorescent chemosensors containing thiazole derivatives, ((E)-2-(4-hydroxy-3-(((2-hydroxyphenyl)imino)methyl)phenyl)-3-phenyl thiazolidin-4-one) AM1 and (2,3-bis(4-hydroxy-3-((E)-((2-hydroxyphenyl)imino) methyl) phenyl) thiazolidin-4-one) AM2, have been fabricated. The probes AM1 and AM2 were prepared using the condensation reaction between 2-hydroxy-5-(4-oxo-3-phenyl thiazolidin-2-yl) benzaldehyde and 2-aminophenol for the probe AM1 and 5,5'-(4-oxothiazolidine-2,3-diyl)bis(2-hydroxy benzaldehyde) and 2-aminophenol for the probe AM2. Afterwards, they were analyzed by various types of NMR and FT-IR spectroscopy, ESI-MS spectra, and elemental anayzer. As a second step, each fabricated chemosensor was able to use turn on fluorescence sensing for detecting of Al3+ ions in ACN/H2O (v/v = 50/50, 10.0 µM, pH = 7.0) solution. Clear complexes formed between the probe AM1 and Al3+ ions and also the probe AM2 and Al3+ ions was determined by not only 1H NMR titration study but also calculated by using the Job's plot. The limit of detection (LOD) value was found to be 0.11 µM (AM1) and 4.4 µM (AM2) for Al3+ ions. Likewise, cell imaging and in vitro cytotoxicity experiments of Al3+ ions in Human epithelium Lovo cells exhibited that prepared chemosensors had low cytotoxicity and blue fluorescence when they treated with of Al3+ ions in the cellular system.

Fluorescence "Turn On-Off" Sensing of Copper (II) Ions Utilizing Coumarin-Based Chemosensor: Experimental Study, Theoretical Calculation, Mineral and Drinking Water Analysis.

Herein, we report the preparation of a fluorescent sensor based on coumarin derivative for copper (II) ion sensing in CH3CN/HEPES media. 6,7-dihydroxy-3-(4-(trifluoro)methylphenyl)coumarin (HMAC) sensor was fabricated and analyzed by spectroscopic techniques. The sensor demonstrates "turn on-off" fluorescence quenching in the presence of copper (II) ions at 458 nm. A clear complex between the chemosensor HMAC and copper (II) ions was characterized by ESI-MS as well as the Job's method. Also, the limit of detection (LOD, 3σ/k) value was determined as 24.5 nM in CH3CN/HEPES (95/5, v/v) buffer media (pH = 7.0). This value is lower than the admissible level of copper (II) ions in drinking water (maximum 31.5 µM) reported by EU Water Framework Directive (WFD) and World Health Organization (WHO) guidelines. The theoretical calculations (density functional theory, DFT) have been performed for the geometric optimized structures. As a final stage, real sample analyses have successfully been performed by using HMAC, as well as ICP-OES method. The relative standard deviation for copper (II) in mineral and drinking water samples has been determined to be below 0.15% and recovery values are in the range of 95.48-109.20%.