Spectrochim Acta A Mol Biomol Spectrosc
December 2023
The present study developed an efficient fluorescent approach, based on a supramolecular assembly between gold nanoclusters and calix[4]arene derivatives (C4A-Ds), to detect sever pollutant of perfluorooctane sulfonic acid (PFOS). For that, a series of C4A-Ds with different chain lengths and positive charges at the wider rim were designed and synthesized. Cytidine-5' phosphate protected gold nanoclusters (AuNCs@CMP) were then assembled with calix[4]arene (LC4AP) to form AuNCs/LC4AP assembly, leading to 8-fold luminescence enhancement via the AIEE effect.
View Article and Find Full Text PDFHuman papillomavirus (HPV) infections are the cause of warts, lesions and cancer, with different types of HPV causing different symptoms. HPV infections are the primary cause of cervical cancer. There are over 220 different types of HPV, and only nine of these can currently be vaccinated.
View Article and Find Full Text PDFHuman African Trypanosomiasis (HAT) is a neglected tropical disease caused by the parasitic protozoan Trypanosoma brucei (T. b.), and affects communities in sub-Saharan Africa.
View Article and Find Full Text PDFHuman African Trypanosomiasis (HAT), a neglected disease endemic in Sub- Saharan Africa, is usually fatal if left untreated. It is caused by the parasite Trypanosoma brucei, and is spread by the tsetse fly. The drugs currently available to treat HAT are few, and limited in efficacy.
View Article and Find Full Text PDFThe thermal annealing behaviour of an electrolyte-triggered calixarene hydrogelator is found to depend strongly on the specific metal chloride used. While the lithium chloride gel showed typical gel-sol transitions as a function of temperature, the magnesium chloride gel was found to repeatedly strengthen with heat-cool cycles. Structural investigations using small-angle neutron scattering, and scanning probe microscopy, suggest that the annealing behaviour is associated with a change in morphology of the fibrous structures supporting the gel.
View Article and Find Full Text PDFThe assembly and disassembly of supramolecular gel fibres are observed using variable temperature scanning probe microscopy. The results show that fibre formation can be monitored at high resolution at a surface, and the final fibre morphologies are broadly consistent with those found by analysis of the bulk gel. The impact of a gelation inhibitor upon the fibre morphology is successfully investigated, providing direct evidence for the mechanism of inhibition as a function of additive concentration.
View Article and Find Full Text PDFThree new calixarene Tl(+) ionophores have been utilized in Tl(+) ion-selective electrodes (ISEs) yielding Nernstian response in the concentration range of 10(-2)-10(-6)M TlNO3 with a non-optimized filling solution in a conventional liquid contact ISE configuration. The complex formation constants (logβIL) for two of the calixarene derivatives with thallium(I) (i.e.
View Article and Find Full Text PDFSolution-phase and solid-state structural studies indicate that the remarkable hydrogelation properties of a proline-functionalised calix[4]arene emerge as a result of extended helical structures formed via inclusion of a proline moiety in a neighbouring calixarene cavity.
View Article and Find Full Text PDFChem Commun (Camb)
September 2008
A water-soluble, chiral calix[4]arene has been found to form hydrogels when triggered by the presence of specific anions, with efficacy linked to the Hofmeister series; the gel properties are modified by the associated cations, and gelation can be reversibly switched off by increasing pH.
View Article and Find Full Text PDFStructural studies of seven very differently functionalised derivatives of calix[4]arene have been used to provide an analysis of the numerous factors which may influence solvent adduct formation by calixarenes. Evidence is presented that even where a solvent guest is included within the calixarene cavity, interactions solely within the cavity cannot be seen as the sole influences upon the guest position and orientation.
View Article and Find Full Text PDFThe Lewis acid catalyzed condensation of 3-methoxyphenol with octanal produced the C(4) symmetric calix[4]resorcinarene 2, in high yield. Of the numerous stereo- and regioisomers possible, the rccc isomer with C(4) symmetry was the only product isolated (as a racemate). The structure has been established by single-crystal X-ray structure analysis.
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