A Fluorescent Furan-based Probe with Protected Functional Groups for Highly Selective and Non-Toxic Imaging of HT-29 Cancer Cells and 4T1 Tumors.

Most of the previously reported fluorescent organic probes for cancer cell and tumor imaging have significant limitations including chemical toxicity, structural instability, low Stokes shift value, and the inability for selective accumulations in tumors during in vivo imaging. To overcome the mentioned challenges, we synthesized the fluorescent probes with protected polar functional groups to enhance the non-toxicity nature and increase the selectivity toward tumors. In addition, the structural rigidity of the fluorescent probes was increased by embedding aromatic rings in the probe structure. This issue enables us to obtain ultrabright cell images due to enhanced fluorescence quantum yield (ΦFL) values. After synthesis and spectral characterizations, the applicability of two furan-based and imidazole-based fluorescent probes ( abbreviated as DCPEF and DBPPI, respectively) was investigated for ultrabright in vitro and in vivo imaging of cancer cells. The probe DCPEF shows the ΦFL value of 0.946 and the Stocks shift of 86 nm. In addition, probe DBPPI offers the ΦFL value of 0.400 and a Stocks shift of 150 nm. The MTT colorimetric cytotoxicity assay showed that probe DCPEF has minimal effects against HT-29 (cancer) and Vero (normal) cells. The probe DCPEF produced ultrabright fluorescence images from HT-29 cells. In addition, in vivo imaging of cancer cells showed that probe DCPEF selectively accumulates in the 4T1 tumor in mice. The spectral and chemical stability, minimal cytotoxicity, significant Stokes shift, and high degree of selectivity for tumor cells during in vivo imaging make DCPEF an appropriate candidate to be used as a standard probe for cancer cell imaging.

Reinvigorating aza-Michael reactions under ionic liquid catalysis: a greener approach.

Cholinium α-amino carboxylates, which debuted in the ionic liquid arena over a decade ago, exhibit superior stability and suitable physical properties relative to other RTILs. Although synthetic pursuits in such media, leveraging their dual role as solvents and catalysts, have been scarce so far, we herein illustrate their catalytic advantage in aza-Michael reactions in terms of low loading, acceleration and improved yields with respect to conventional conditions and other imidazolium-based ILs. These highly structured salts most likely act through multiple and cooperative non-covalent interactions. These mechanistic features have also been investigated through high-level computational analyses as well.

Unlocking the Potential of Chemically Modified Carbon Gels in Gallic Acid Adsorption.

This study deals with the preparation of adsorbents from a commercial xerogel by chemically modifying its surface with concentrated mineral acids and alkali metal chlorides, their physicochemical characterization, and their use as adsorbents for gallic acid in aqueous solution. Although there are publications on the use of carbon xerogels as adsorbents, we propose and study simple modifications that can change their chemical properties and, therefore, their performance as adsorbents. The adsorbate of choice is gallic acid and, to our knowledge, there is no history of its adsorption with carbon xerogels. The prepared adsorbents have a high specific surface area (347-563 m2 g-1), better pore development for samples treated with alkali metal chlorides than with mineral acids, and are more acidic than the initial xerogel (p.z.c range 2.49-6.87 vs. 7.20). The adsorption equilibrium is reached in <16 h with a kinetic constant between 0.018 and 0.035 h-1 for the pseudo-second-order model. The adsorption capacity, according to the Langmuir model, reaches 62.89 to 83.33 mg g-1. The adsorption properties of the commercial xerogel improved over a wide range of pH values and temperatures. The experimental results indicate that the adsorption process is thermodynamically favored.

Hydrothermal Carbon Coating of an Activated Carbon-A New Adsorbent.

A new adsorbent material was prepared by coating an activated carbon with hydrothermal carbon obtained from sucrose. The material obtained has different properties from the sum of the properties of the activated carbon and the hydrothermal carbon, which shows that a new material was obtained. It has a high specific surface area (1051.9 m2 g-1) and is slightly more acidic than the starting activated carbon (p.z.c.-point of zero charge 8.71 vs. 9.09). The adsorptive properties of a commercial carbon (Norit RX-3 Extra) were improved over a wide pH and temperature range. The capacity values of the monolayer according to Langmuir's model reached 588 mg g-1 for the commercial product and 769 mg g-1 for the new adsorbent.

Ring Opening Polymerization Used for the Production of VOC Free High-Performance Ecofriendly Novel PBZ/PDA/CeO2 Nanocomposites.

This study analyzed the fabrication and characterization of polybenzoxazine/polydopamine/ceria as tertiary nanocomposites. To this end, a new benzoxazine monomer (MBZ) was fabricated based on the well-known Mannich reaction of naphthalene-1-amine, 2-tert-butylbenzene-1,4-diol and formaldehyde under ultrasonic-assisted process. Polydopamine (PDA) was used as dispersing polymer nanoparticles and surface modifier for CeO2 by in-situ polymerization of dopamine with the assistance of ultrasonic waves. Then, nanocomposites (NC)s were manufactured by in-situ route under thermal conditions. The FT-IR and 1H-NMR spectra confirmed the preparation of the designed MBZ monomer. The FE-SEM and TEM results showed the morphological aspects of prepared NCs and illustrated the distribution of CeO2 NPs in the polymer matrix. The XRD patterns of NCs showed the presence of crystalline phases of nanoscale CeO2 in an amorphous matrix. The TGA results reveal that the prepared NCs are classified as thermally stable materials.

Synthesis and application of the fluorescent furan and imidazole probes for selective in vivo and in vitro cancer cell imaging.

Development of imaging probes for identification of tumors in the early stages of growth can significantly reduce the tumor-related health hazards and improve our capacity for treatment of cancer. In this work, three different furan and imidazole fluorescent derivatives abbreviated as Cyclo X, SAC and SNO are introduced for in vivo and in vitro imaging of cancer cells. The fluorescence quantum yield values were 0.226, 0.400 and 0.479 for Cyclo X, SAC and SNO, respectively. The excitation and emission wavelengths of maximum intensity were (360, 452), (350, 428) and (350, 432) nm for Cyclo X, SAC and SNO, respectively. The MTT reduction assay was used to estimate the cytotoxic activity of the proposed derivatives against HT-29 (cancer) and Vero (normal) cell lines. Cyclo X showed no cytotoxic effect, while SAC and SNO showed significantly higher cytotoxicity against the tested cell lines than cisplatin as a well-known anticancer drug. In vitro fluorescence microscopic images obtained using HT-29 cells showed that Cyclo X produced very bright images. The in vivo cancer cell imaging using 4T1 tumor-bearing mice revealed that Cyclo X is selectively accumulated in the tumor without distribution in the mice body organs. The spectral and structural stability, large Stokes shift, non-cytotoxicity and high level of selectivity for in vivo imaging are properties that make Cyclo X a suitable candidate to be used for long-term monitoring of cancer cells.

Synthesis and characterisation of acid/basic modified adsorbents. Application for chlorophenols removal.

A commercial activated carbon was modified with acid and basic reagents -an acidic one via treatment with sulphuric acid and a basic via treatment with pentaethylenehexamine- to yield adsorbents with different surface acid/base character. These modified adsorbents were characterised by elemental and immediate analysis, N2 adsorption, XPS and point zero charge measurements. The new adsorbents were tested for chlorophenols removal in water (4-chlorophenol, 3,5-dichlorophenol, 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol) at different temperatures. Although the calculated process enthalpy was positive for all cases, indicating an endothermic process, the entropy was positive, resulting in a negative Gibbs free energy and spontaneous process. The adsorption capacity increases with temperature and decreases when the phenols' number of substituents increases. The modified acid-activated carbon demonstrated an exciting higher adsorbing capacity from 426.9 to 742.3 mg g-1 for 2,4,6-trichlorophenol, whereas the adsorption capacity for the basic ranged between 142.9 and 238.0 mg g-1. The Langmuir model satisfactorily fitted the adsorption equilibrium data for all chlorophenol contaminants.