Cation Receptor Research Articles

Revealing the origin of dendritic deposition regulated solid electrolyte interphase enabled by cation receptor in Zn-ion batteries

Aqueous Zn-metal batteries open up promising prospects for large-scale energy storage due to the advantages of ample components, cost-effectiveness, and safety features. However, the notorious dendritic development and unavoidable hydrogen evolution reaction of Zn have grown to be one of the main barriers inhibiting its further commercialization. Despite substantial studies, the mechanism of nucleation and deposition of Zn2+ ions on zinc layer surfaces remains elusive. Here, inspired by additive, the SnCl2 additive is introduced to initiate the in-situ formation of the ZnS-rich solid electrolyte interphase (SEI) layer on the Zn anode, which creates a protective “shielding effect” that hinders direct contact between water and the zinc surface, suppressing the random growth of Zn dendrites in the whole process. The mechanism of Zn nucleation was revealed by employing high-resolution transmission electron microscopy, consecutive electron diffraction coupled with finite element method (FEM) simulations. Moreover, spontaneously formed 3D architecture consists of micorsized hemispherical Sn particles not only suppresses the Zn dendrite growth by reducing the local current density, but also enables the lateral growth of Zn crystals by increasing the average surface energy. Such an electrolyte enables a long cycle life of over 2000 h in the Zn||Zn cell. Importantly, the assembled Zn||MnVO full cells with SnCl2 electrolyte also delivers substantial capacity (171.1mA h g−1 at 1 A h g−1), presenting a promising application. These discoveries not only deepen the comprehension of fundamental scientific knowledge regarding the microscopic reaction mechanism of the Zn anode but also offer significant insights for optimizing performance.

Synthesis and Characterization of Amido-Thiourea Based p-tert-butylcalix[4]arene Compound and Investigation of Transition Metal Complex Properties

In host-guest complexes, the compatibility of the size and shape of the host cavity and the guest molecule is essential in the formation of the host-guest complex. Considered third-generation macrocyclic hosts, calixarenes attract the attention of researchers in supramolecular chemistry as they offer a wide range of applications in fields such as biocatalysis, enzyme analysis, pharmaceuticals, and biosensing. The synthesis of host molecules for anionic and cationic guest compounds has a very important place in coordination chemistry. Calixarenes are known as one of the important types of supramolecular compounds and are an important class of easily synthesized compounds that can act as a suitable receptors for cations, anions, and organic molecules. When calixarene compounds, which have an important place in host-guest chemistry, are derivatized appropriately, the coordination ability of the molecule against metal cations increases. These derivatizations gained importance due to the sensory properties of the molecule, and different studies were started considering that a larger cavity and functional group are required for more guest molecules. In this study, a new ligand of 1,3-disubstituted p-tert-butylcalix[4]arene derivative with increased donor atomic number with amide and thiourea groups in its structure was synthesized. Co(II), Ni(II), Cu(II), and Zn(II) complexes were synthesized with the compound and the structures of the compounds were characterized by UV-vis, FT-IR, 1H-NMR, 13C-NMR, and mass spectrometry.

Solvent Acts as the Referee in a Match-Up Between Charged and Preorganized Receptors.

The prevalence of anion-cation contacts in biomolecular recognition under aqueous conditions suggests that ionic interactions should dominate the binding of anions in solvents across both high and low polarities. Investigations of this idea using titrations in low polarity solvents are impaired by interferences from ion pairing that prevent a clear picture of binding. To address this limitation and test the impact of ion-ion interactions across multiple solvents, we quantified chloride binding to a cationic receptor after accounting for ion pairing. In these studies, we created a chelate receptor using aryl-triazole CH donors and a quinolinium unit that directs its cationic methyl inside the binding pocket. In low-polarity dichloromethane, the 1 : 1 complex (log K1 : 1 ~ 7.3) is more stable than neutral chelates, but fortuitously comparable to a preorganized macrocycle (log K1 : 1 ~ 6.9). Polar acetonitrile and DMSO diminish stabilities of the charged receptor (log K1 : 1 ~ 3.7 and 1.9) but surprisingly 100-fold more than the macrocycle. While both receptors lose stability by dielectric screening of electrostatic stability, the cationic receptor also pays additional costs of organization. Thus even though the charged receptor has stronger binding in apolar solvents, the uncharged receptor has more anion affinity in polar solvents.

Rapidly Synthesized Single‐Ion Conductive Hydrogel Electrolyte for High‐Performance Quasi‐Solid‐State Zinc‐ion Batteries

AbstractSingle‐ion conductive electrolytes can largely eliminate electrode polarization, reduce the proportion of anion migration and inhibit side reactions in batteries. However, they usually suffer from insufficient ion conductivity due to the strong interaction between cations and cationic receptors. Here we report an ultrafast light‐responsive covalent organic frameworks (COF) with sulfonic acid groups modification as the acrylamide polymerization initiator. Benefiting from the reduced electrostatic interaction between Zn2+ and sulfonic acid groups through solvation effects, the as‐prepared COF‐based hydrogel electrolyte (TCOF‐S‐Gel) receives an ion conductivity of up to 27.2 mS/cm and Zn2+ transference number of up to 0.89. In addition, sufficient hydrogen bonds endow the single‐ion conductive TCOF‐S‐Gel electrolyte to have good water retention and superb mechanical properties. The assembled Zn||TCOF‐S‐Gel||MnO2 full zinc‐ion battery exhibits high discharge capacity (248 mAh/g at 1C), excellent rate capability (90 mAh/g at 10C) and superior cycling performance. These enviable results enlist the instantaneously photocured TCOF‐S‐Gel electrolyte to be qualified to large‐scaled flexible high‐performance quasi‐solid‐state zinc‐ion batteries.

Rapidly Synthesized Single-Ion Conductive Hydrogel Electrolyte for High-Performance Quasi-Solid-State Zinc-ion Batteries.

Single-ion conductive electrolytes can largely eliminate electrode polarization, reduce the proportion of anion migration and inhibit side reactions in batteries. However, they usually suffer from insufficient ion conductivity due to the strong interaction between cations and cationic receptors. Here we report an ultrafast light-responsive covalent organic frameworks (COF) with sulfonic acid groups modification as the acrylamide polymerization initiator. Benefiting from the reduced electrostatic interaction between Zn2+ and sulfonic acid groups through solvation effects, the as-prepared COF-based hydrogel electrolyte (TCOF-S-Gel) receives an ion conductivity of up to 27.2 mS/cm and Zn2+ transference number of up to 0.89. In addition, sufficient hydrogen bonds endow the single-ion conductive TCOF-S-Gel electrolyte to have good water retention and superb mechanical properties. The assembled Zn||TCOF-S-Gel||MnO2 full zinc-ion battery exhibits high discharge capacity (248 mAh/g at 1C), excellent rate capability (90 mAh/g at 10C) and superior cycling performance. These enviable results enlist the instantaneously photocured TCOF-S-Gel electrolyte to be qualified to large-scaled flexible high-performance quasi-solid-state zinc-ion batteries.

Intestinal enteroendocrine cells rely on ryanodine and IP3 calcium store receptors for mechanotransduction.

Enteroendocrine cells (EECs) are specialized sensors of luminal forces and chemicals in the gastrointestinal (GI) epithelium that respond to stimulation with a release of signalling molecules such as serotonin (5-HT). For mechanosensitive EECs, force activates Piezo2 channels, which generate a very rapidly activating and inactivating (∼10ms) cationic (Na+ , K+ , Ca2+ ) receptor current. Piezo2 receptor currents lead to a large and persistent increase in intracellular calcium (Ca2+ ) that lasts many seconds to sometimes minutes, suggesting signal amplification. However, intracellular calcium dynamics in EEC mechanotransduction remain poorly understood. The aim of this study was to determine the role of Ca2+ stores in EEC mechanotransduction. Mechanical stimulation of a human EEC cell model (QGP-1) resulted in a rapid increase in cytoplasmic Ca2+ and a slower decrease in ER stores Ca2+ , suggesting the involvement of intracellular Ca2+ stores. Comparing murine primary colonic EECs with colonocytes showed expression of intercellular Ca2+ store receptors, a similar expression of IP3 receptors, but a >30-fold enriched expression of Ryr3 in EECs. In mechanically stimulated primary EECs, Ca2+ responses decreased dramatically by emptying stores and pharmacologically blocking IP3 and RyR1/3 receptors. RyR3 genetic knockdown by siRNA led to a significant decrease in mechanosensitive Ca2+ responses and 5-HT release. In tissue, pressure-induced increase in the Ussing short circuit current was significantly decreased by ryanodine receptor blockade. Our data show that mechanosensitive EECs use intracellular Ca2+ stores to amplify mechanically induced Ca2+ entry, with RyR3 receptors selectively expressed in EECs and involved in Ca2+ signalling, 5-HT release and epithelial secretion. KEY POINTS: A population of enteroendocrine cells (EECs) are specialized mechanosensors of the gastrointestinal (GI) epithelium that respond to mechanical stimulation with the release of important signalling molecules such as serotonin. Mechanical activation of these EECs leads to an increase in intracellular calcium (Ca2+ ) with a longer duration than the stimulus, suggesting intracellular Ca2+ signal amplification. In this study, we profiled the expression of intracellular Ca2+ store receptors and found an enriched expression of the intracellular Ca2+ receptor Ryr3, which contributed to the mechanically evoked increases in intracellular calcium, 5-HT release and epithelial secretion. Our data suggest that mechanosensitive EECsrely on intracellular Ca2+ stores and are selective in their use of Ryr3 for amplification of intracellular Ca2+ . This work advances our understanding of EEC mechanotransduction and may provide novel diagnostic and therapeutic targets for GI motility disorders.

Characterization of the Interaction of Nerve Agent Mimics with Selected Synthetic Receptors

Qualitative NMR spectroscopic and quantitative calorimetric binding studies were performed to characterize the interaction of nontoxic mimics of the V-type nerve agent VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate) and the Novichok nerve agent A-234 (ethyl (1-(diethylamino)ethylidene)phosphoramidofluoridate) with a series of receptors in 100 mM aqueous phosphate buffer at pH 7.4 and 37 °C. These investigations provided information about the preferred geometry with which the nerve agent mimics are included into the receptor cavities and about the stability of the complexes formed. According to the results, the positively charged VX mimic prefers to bind to cation receptors such as sulfonated calixarenes and an acyclic cucurbituril but does not noticeably interact with cyclodextrins. While binding to the acyclic cucurbituril is stronger than that to calixarenes, the mode of inclusion into the sulfonatocalix[4]arene cavity is better suited for the development of scavengers that bind and detoxify V-type nerve agents. The neutral Novichok mimic, on the other hand, only interacts with the acyclic cucurbituril with a strength required for scavenger development. These binding studies thus provided guidelines for the further development of nerve agent scavengers.

Synthesis, characterization and hirshfeld surface analyses of Ni(mnt)-alkyl bis(imidazolium) ion pair compounds: Supramolecular interactions mediated self-assembly

A series of five new ion pair compounds with formulae [C9H14N4][Ni(mnt)2](CH3CN) (1a), [C10H16N4][Ni(mnt)2] (1b), [C11H18N4][Ni(mnt)2] (1c), [C12H20N4][Ni(mnt)2] (1d), [C13H22N4][Ni(mnt)2] (1e) have been synthesized from Ni(II) salts, Na2mnt (disodium maleonitriledithiolate) and alkyl-bis(imidazolium) cations [C8H12(CH2)nN4Br2] (n = 1 − 5). All the compounds were characterized by IR, elemental analyses, UV, and electrochemical studies. The solid-state structures of these compounds were characterized by single crystal X-diffraction, facilitated by Hirshfeld surface analyses, to quantify the type and magnitude of various non-covalent interactions controlling the self-assembly. Various supramolecular interactions CHcation···Nanion, CHcation···Sanion and CH···π play a crucial role in modulating the conformations of cationic and anionic receptors as well as mediating the self-assembly. Hirshfeld surface analyses reveals that supramolecular packing is dominated by the directional interactions in lower chain cationic receptors whereas, non-directional interactions operate in longer chain cationic receptors. Absorption spectra reveals compound 1d exhibits absorption band (diffuse reflectance) at 910 nm whereas others at 860 nm. All the compounds show oxidative response in the region 0.48−0.56 V in the electrochemical studies. Additionally, the phase purity of the compounds were confirmed by the powder X-ray diffraction studies.

The Role of Triazole and Glucose Moieties in Alkali Metal Cation Complexation by Lower-Rim Tertiary-Amide Calix[4]arene Derivatives.

The binding of alkali metal cations with two tertiary-amide lower-rim calix[4]arenes was studied in methanol, N,N-dimethylformamide, and acetonitrile in order to explore the role of triazole and glucose functionalities in the coordination reactions. The standard thermodynamic complexation parameters were determined microcalorimetrically and spectrophotometrically. On the basis of receptor dissolution enthalpies and the literature data, the enthalpies for transfer of reactants and products between the solvents were calculated. The solvent inclusion within a calixarene hydrophobic basket was explored by means of 1H NMR spectroscopy. Classical molecular dynamics of the calixarene ligands and their complexes were carried out as well. The affinity of receptors for cations in methanol and N,N-dimethylformamide was quite similar, irrespective of whether they contained glucose subunits or not. This indicated that sugar moieties did not participate or influence the cation binding. All studied reactions were enthalpically controlled. The peak affinity of receptors for sodium cation was noticed in all complexation media. The complex stabilities were the highest in acetonitrile, followed by methanol and N,N-dimethylformamide. The solubilities of receptors were greatly affected by the presence of sugar subunits. The medium effect on the affinities of calixarene derivatives towards cations was thoroughly discussed regarding the structural properties and solvation abilities of the investigated solvents.

Organic Cation Receptor for Colorimetric Lateral Flow Device: Detection of Zearalenone in Food Samples.

As per the WHO reports, it has been estimated that almost 25% of food crops contain mycotoxins as the major contaminant. In this work, we developed a paper-based colorimetric lateral flow device (CLFD) impregnated with an organic cation receptor (OCR) for sensitive and selective detection of zearalenone (ZEN). Various techniques such as ultraviolet (UV)-visible absorption, cyclic voltammetry, and fluorescence spectroscopy were used for the detection of mycotoxins, and it was observed that OCR shows sensitivity and selectivity toward zearalenone (ZEN) only, irrespective of any other analytes. Furthermore, the colorimetric test revealed that the developed OCR shows a change in color with the addition of ZEN from greenish-gray to blue that is visible to the naked eye. The quantification of ZEN was also achieved using RGB analysis and compared with UV-visible spectroscopy data. Further, for the on-site detection of ZEN, a paper-based CLFD was also developed and used to evaluate the spiked corn sample containing ZEN, and it provided significant results with a limit of detection (LOD) of 0.31 nM (3σ method), good linearity (R2 = 0.9702), good reproducibility (SD = ±6%, triplicate), and good recovery of ZEN of 95-102% with a variation coefficient (VC) varying from 1.56 to 4.62%. Therefore, the device has the potential to check the mycotoxin toxicity in food products and is helpful in remote and developing areas.

2-Ferrocenylimidazole-based multiresponsive receptors for Al3+, Cu2+, and H2PO4− ions: Effect of structural modification on the ion sensing performance

Two 2-ferrocenylimidazoles decorated with two pyridyl arms, 2-ferrocenyl-4,5-di(2-pyridyl)-1H-imidazole (L1) and 2-ferrocenyl-4,5-di(3-pyridyl)-1H-imidazole (L2), have been synthesized as potential multichannel ditopic receptors for cations and anions, owing to the presence of redox, chromogenic and fluorescent groups at the imidazole core. The structures of L1 and its Ag(I) complex (I) [L12·Ag2·(NO3)2] were further confirmed by X-ray crystal analysis. The most salient features derived from sensing studies are that L1 behaves as a highly selective fluorescent “turn-on” receptor for Al3+ and Cu2+ cations, whereas L2 acts as a dual fluorescent “turn-on” and redox selective receptor for H2PO4− anions. This significant change in fluorescent sensing selectivity is due to the change in the relative position of N atoms in the pyridyl groups. Furthermore, the resulting complexes of L1-Al3+ and L1-Cu2+ systems are able to detect Br− and I− by color changes. The sensing mechanism and binding mode of these two receptors were confirmed by titration spectra and ESI-MS. Finally, living cell imaging experiments demonstrated the value of L1 in the fluorescent visualization of Al3+ ions in biological systems.

Unique Photophysical Properties of 1,8-Naphthalimide Derivatives: Generation of Semi-stable Radical Anion Species by Photo-Induced Electron Transfer from a Carboxy Group.

The development of anion sensors for selective detection of a specific anion is a crucial research topic. We previously reported a selective photo-induced colorimetric reaction of 1-methyl-3-(N-(1,8-naphthalimidyl)ethyl)imidazolium (MNEI) having a cationic receptor in the presence of molecules having multiple carboxy groups, such as succinate, citrate, and polyacrylate. However, the mechanism underlying this reaction was not clarified. Here, we investigate the photo-induced colorimetric reaction of N-[2-(trimethylammonium)ethyl]-1,8-naphthalimide (TENI), which has a different cationic receptor from MNEI and undergoes the photo-induced colorimetric reaction, and its analogues to clarify the reaction mechanism. The TENI analogues having substituents on the naphthalene ring provide important evidence, suggesting that the colorimetric chemical species were radical anions generated via photo-induced electron transfer from carboxylate to the naphthalimide derivative. The generation of the naphthalimide-based radical anion is verified by 1H NMR and cyclic voltammetry analyses, and photo-reduction of methylene blue is mediated by TENI. In addition, the role of the cationic receptor for the photo-induced colorimetric reaction is investigated with TENI analogues having different hydrophilic groups instead of the trimethylammonium group. Interestingly, the photo-induced colorimetric reaction is observed in a nonionic analogue having a polyethylene glycol group, indicating that the colorimetric reaction does not require a cationic receptor. On the other hand, we reveal that the trimethylammonium group stabilizes the radical anion species. These generation and stabilization phenomena of naphthalimide-based radical anion species will contribute to the development of sophisticated detection systems specific for carboxylate.

Synthesis and characterization of novel acylthiourea compounds used in ions recognition and sensing in organic media

A series of novel N-acyl-N’-aryl thiourea derivatives were designed and prepared with the aim to develop dual responsive receptors for anions and cations. The structure of the new products was confirmed by NMR spectroscopy (13C and 1H), elemental analysis, and IR spectroscopy. Their thermal stability was studied by thermogravimetric analysis (TG) and it was found that these acyl thiourea derivatives are stable up to 160 °C. The ion recognition and sensing properties of the acyl thiourea compounds were investigated by UV–VIS absorption spectroscopy in organic media upon the addition of various salts. The UV–VIS studies revealed that these acyl thiourea derivatives are able to sense biological important ions such as fluoride and copper (II) ions.

Functionalized resorcinarenes effectively disrupt the aggregation of αA66-80 crystallin peptide related to cataracts.

Cataracts, an eye lens clouding disease, are debilitating and while operable, remain without a cure. αA66-80 crystallin peptide abundant in cataracted eye lenses contributes to aggregation of αA-crystallin protein leading to cataracts. Inspired by the versatility of macrocycles and programmable guest selectivity through discrete functionalizations, we report on three water-soluble ionic resorcinarene receptors (A, B, and C) that disrupt the aggregation of αA66-80 crystallin peptide. A and B each possess four anionic sulfonate groups, while C includes four cationic ammonium groups with four flexible extended benzyl groups. Through multiple non-covalent attractions, these receptors successfully disrupt and reverse the aggregation of αA66-80 crystallin peptide, which was studied through spectroscopic, spectrometric, calorimetric, and imaging techniques. The αA66-80·receptor complexes were also explored using molecular dynamics simulation, and binding energies were calculated. Even though each of the three receptors can bind with the peptide, receptor C was characterized by the highest binding energy and affinity for three different domains of the peptide. In effect, the most efficient inhibitor was a cationic receptor C via extended aromatic interactions. These results highlight the potential of versatile and tunable functionalized resorcinarenes as potential therapeutics to reverse the aggregation of α-crystallin dominant in eye cataracts.

Recognition-mediated supramolecular assemblies of 4ˊ,6-diamidino-2-phenylindole (DAPI) with cationic receptors: Modulation in the photophysical properties and prospects

Recognition-mediated supramolecular assemblies of 4ˊ,6-diamidino-2-phenylindole (DAPI) with cationic receptors: Modulation in the photophysical properties and prospects

Self-assembly of imidazolium/benzimidazolium cationic receptors: their environmental and biological applications

This review highlights the applications of imidazolium based cationic receptors for sensing of biomolecules and catalysis.

Strapped calix[4]pyrroles: from syntheses to applications.

Supramolecular chemistry is a central topic in modern chemistry. It touches on many traditional disciplines, such as organic chemistry, inorganic chemistry, physical chemistry, materials chemistry, environmental chemistry, and biological chemistry. Supramolecular hosts, inter alia macrocyclic hosts, play critical roles in supramolecular chemistry. Calix[4]pyrroles, non-aromatic tetrapyrrolic macrocycles defined by sp3 hybridized meso bridges, have proved to be versatile receptors for neutral species, anions, and cations, as well as ion pairs. Compared to the parent system, octamethylcalix[4]pyrrole and its derivatives bearing simple appended functionalities, strapped calix[4]pyrroles typically display enhanced binding affinities and selectivities. In this review, we summarize advances in the design and synthesis of strapped calix[4]pyrroles, as well as their broad utility in molecular recognition, supramolecular extraction, separation technology, ion transport, and as agents capable of inhibiting cancer cell proliferation. Future challenges within this sub-field are also discussed.

Mechanistic insights into heavy metal ion sensing by NOS2-macrocyclic fluorosensors via the structure-function relationship: influences of fluorophores, solvents and anions.

To obtain a mechanistic understanding of the effects derived from fluorophores, solvents and anions on heavy metal sensing, two NOS2-macrocycle-based fluorosensors with different fluorophores (L1: 9-methylanthracene, L2: benzothiazolyl) were synthesised. In this regard, particular attention was given to monitoring the cation-ligand, cation-anion and cation-solvent interactions from the detailed complexation processes in both the solution and solid states while considering the structure-function relationship. L1 showed turn-on type silver(i) selectivity over other metal ions, including mercury(ii), in ethanol. According to the complexation results obtained by titration (UV-vis, fluorescence and NMR), cold-spray ionization mass spectrometry and X-ray crystallography, the observed silver(i) sensing by L1 is mainly due to its 1 : 1 complexation with silver(i) via the Ag-Ntert bond and the strong solvation of mercury(ii). Thus, the turn-on sensing for silver(i) can be explained by the CHEF effect, in which the coordination of silver(i) to the receptor unit effectively prevents PET quenching. As a dual-probe (UV-vis and fluorescence) chemosensor, L2 showed fluorescence turn-off type selectivity for both silver(i) and mercury(ii) in ethanol. In acetonitrile, L2 showed improved fluorescence turn-off type selectivity for mercury(ii) with ClO4- and NO3-; however, no such responses were observed with other anions, such as Cl-, Br-, I-, SCN-, OAc- and SO42-. Together with the complexation results by titration, the crystal structures of an endocyclic mercury(ii) perchlorate complex and an exocyclic mercury(ii) iodide complex revealed that the anion-controlled mercury(ii) sensing by L2 arises from the endo- and exo-coordination modes depending on the anion coordinating ability, which induces either metal-receptor/fluorophore binding (Hg-Ntert and Hg-Nfl) or no binding. Taken collectively, the photophysical, thermodynamic and structural results of the complexations herein suggest that the sensing properties of heavy metal ions by macrocycle-based fluorosensors are very sensitive not only to the cation-receptor and cation-fluorophore interactions but also to the cation-anion (endo/exo-coordination modes) and/or cation-solvent interactions.

Helically shaped cation receptor: design, synthesis, characterisation and first application to ion transport.

The methyl ester of 8-oxo-8H-indeno[2′,1′:7,8]naphtho[1,2-b]thiophene-2-carboxylic acid (1) and its corresponding PEGylated ester were synthesised and fully characterised. X-ray diffraction studies on (1) confirmed the helical structure of the receptor and that it is self-assembled into layers by π–π interactions. An in-depth study by DFT calculations and MS experiments (ESI-MS, MS/MS, IMRPD and ESI-IMS-MS) was carried out between (1) and the physiological cation K+. The formation of supramolecular complexes between (1) and K+ with different stoichiometries was demonstrated and the cation K+ preferentially interacts with the oxygen atoms of the carbonyl bond of the ketone and ester groups and the sulphur atom of the heterocycle. The ability of the two synthesized aromatic architectures to transport ions across a model lipid membrane has been studied by electrophysiology experiments. The formation of pores was observed, even at nanomolar concentrations. Since the PEGylated molecule showed more regular pore definitions than the hydrophobic molecule, the introduction of a polar hydrophilic chain made it possible to control the orientation of the aromatic architectures within the membrane.

Mononuclear lanthanide(III) complexes with tripodal ligands as ammonium cation receptors

Mononuclear lanthanide(III) complexes with tripodal ligands as ammonium cation receptors