Water-Soluble Chalcogenide W6-Clusters: On the Way to Biomedical Applications

Abstract

Despite the great potential of octahedral tungsten cluster complexes in fields of biomedical applications such as X-ray computed tomography or angiography, there is only one example of a water-soluble W6Q8-cluster that has been reported in the literature. Herein we present the synthesis and a detailed characterization including X-ray structural analysis, NMR, IR, UV–Vis spectroscopies, HR-MS spectrometry, and the electrochemical behavior of two new cluster complexes of the general formula W6Q8L6 with phosphine ligands containing a hydrophilic carboxylic group, which makes the complexes soluble in an aqueous medium. The hydrolytic stability of the clusters’ aqueous solutions allows us to investigate for the first time the influence of W6-clusters on cell viability. The results obtained clearly demonstrate their very low cytotoxicity, comparable to the least-toxic clusters presented in the literature.

Unusual Square Pyramidal Chalcogenide Mo5 Cluster with Bridging Pyrazolate-Ligands

“…For example, for triangular clusters having Mo IV , the position of the signal of μ 3 -Se in 77 Se NMR was found at 1356, 700, or 666 ppm for complexes [Mo 3 (μ 3 -Se)(μ-O) 3 (acac) 3 (py) 3 ]PF 6 [ 48 ], (Bu 4 N) 2 [Mo 3 (μ 3 -Se)(μ-Se 2 ) 3 Br 6 ] [ 38 ], and K 2 [Mo 3 (μ 3 -Se)(μ-Se 2 ) 3 (C 2 O 4 ) 3 ] [ 37 ], respectively. The closest example (according to the charge state of the metal) is [{W II 2 W III 4 (μ 3 -Se) i 8 }(Ph 2 PC 2 H 4 COOH) t 6 ] [ 49 ], for which the signal of μ 3 -Se was at 1018 ppm.…”

Molecularly Engineered Room-Temperature Phosphorescence for Biomedical Application: From the Visible toward Second Near-Infrared Window

“…In sharp contrast with common organic molecules, which are primarily excited singlet state emitters, transition metal complexes prefer to decay from excited triplet states and hence can release efficient room-temperature phosphorescence . By sorting out related documents, transition metals for triplet science studies mainly include group VI (Mo and W), VII (Re), and XI (Cu, Ag, Au) elements. − More recently, the coordination of organic ligands with common transition metal ions (e.g., Zn 2+ ) has been proven to be an effective method to realize high-efficiency yellow phosphorescence . These intriguing photoluminescent properties will define their potential applications as emitters for biosensing and bioimaging .…”