Chitosan biosorbents for the recovery of palladium and platinum from aqueous waste streams.

Heterogenization of RuL 3 complexes on a support with proper anchor points provides a route toward design of green catalysts. In this paper, Ru(II) polypyridyl complexes are investigated with the aim to unravel the influence on the photocatalytic properties of varying nitrogen content in the ligands and of embedding the complex in a triazine-based covalent organic framework. To provide fundamental insight into the electronic mechanisms underlying this behavior, a computational study is performed. Both the ground and excited state properties of isolated and anchored ruthenium complexes are theoretically investigated by means of density functional theory and time-dependent density functional theory. Varying the ligands among 2,2′-bipyridine, 2,2′-bipyrimidine, and 2,2′-bipyrazine allows us to tune to a certain extent the optical gaps and the metal to ligand charge transfer excitations. Heterogenization of the complex within a CTF support has a significant effect on the nature and energy of the electronic transitions. The allowed transitions are significantly red-shifted toward the near IR region and involve transitions from states localized on the CTF toward ligands attached to the ruthenium. The study shows how variations in ligands and anchoring on proper supports allows us to increase the range of wavelengths that may be exploited for photocatalysis.

The market shareo fn oncontact temperature sensors is expending due to fast technological and medical evolutions. In the wide varietyo fn oncontact sensors, lanthanide-based temperature sensors stand out. They benefit from high photostability,r elativelyl ong decay times and high quantum yields. To circumvent their low molar light absorption, the incorporationo falight-harvesting antenna is required. This Review provides an overview of the nitrogenrich antennae in lanthanide-based temperature sensors, emitting in the visible light spectrum, and discusses their temperature sensor ability.T he N-rich ligandsa re incorporated in many different platforms. The investigation of different antennae is required to developt emperature sensors with diverse optical properties andt oc reate ad iverse offer for the multiple application fields. Molecular probes, consisting of small molecules, are first discussed. Furthermore, the thermometerp roperties of ratiometric temperature sensors, based on di-and polynuclear complexes,m etal-organic frameworks, periodic mesoporouso rganosilicas andp orous organicp olymers, are summarized. The antenna mainly determines the application potential of the ratiometric thermometer. It can be observed that molecular probesa re operational in the broad physiological range, metal-organic frameworks are generally very useful in the cryogenic region,p eriodic mesoporous organosilica show temperature dependency in the physiological range, and porous organic polymers are operativei n the cryogenic-to-medium temperature range.

Recent studies point towards the possible disadvantages of using hydroxamic acid-based zinc-binding groups in HDAC inhibitors due to mutagenicity issues. In this work, we elaborated on our previously developed Tubathian series, a class of highly selective thiaheterocyclic HDAC6 inhibitors, by replacing the benzohydroxamic acid function by an alternative zinc chelator,, an aromatic trifluoromethyl ketone. Unfortunately, these compounds showed a reduced potency to inhibit HDAC6 as compared to their hydroxamic acid counterparts. In agreement, the most active trifluoromethyl ketone was unable to influence the growth of SK-OV-3 ovarian cancer cells nor to alter the acetylation status of tubulin and histone H3. These data suggest that replacement of the zinc-binding hydroxamic acid function with a trifluoromethyl ketone zinc-binding moiety within reported benzohydroxamic HDAC6 inhibitors should not be considered as a standard strategy in HDAC inhibitor development.

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Grafting of an insoluble phenanthroline-polymer with Eu3+/Tb3+ tfac complexes creates a thermometer with good temperature sensitivity in the broad biological range.

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The challenge of measuring fast moving or small scale samples is based on the absence of contact between sample and sensor. Grafting lanthanides onto hybrid materials arises as one of the most promising accurate techniques to obtain noninvasive thermometers. In this work, a novel bipyridine based porous organic polymer (bpyDAT POP) was investigated as temperature sensor after grafting with Eu(acac)3 and Tb(acac)3 complexes. The bpyDAT POP successfully showed temperature‐dependent behavior in the 10–310 K range, proving the potential of amorphous, porous organic frameworks. We observed unique temperature dependent behavior. More intriguingly, instead of the standard observed change in emission as a result of a change in temperature for both Eu3+ and Tb3+, the emission spectrum of Tb3+ remained constant. This work provides framework‐ and energy‐based explanations for the observed phenomenon. The conjugation in the bpyDAT POP framework is interrupted, creating energetically isolated Tb3+ environments. Energy transfer from Tb3+ to Eu3+ is therefore absent, nor energy back transfer from Tb3+ to bpyDAT POP ligand (i.e. no thermal quenching) is detected.