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Integrating 31P DOSY NMR spectroscopy and molecular mechanics as a powerful tool for unraveling the chemical structures of polyoxomolybdate-based amphiphilic nanohybrids in aqueous solution

, : Integrating 31P DOSY NMR spectroscopy and molecular mechanics as a powerful tool for unraveling the chemical structures of polyoxomolybdate-based amphiphilic nanohybrids in aqueous solution. Chemistry 20(18): 5258-5270

Novel organic-inorganic hybrids of various sizes were generated by reaction of 1,8-octanediphosphonic acid (ODP) and (NH4)6Mo7O24 in aqueous solution. The formation of rodlike hybrids with variable numbers of covalently bound ODP and polyoxomolybdate (POM) units can be tuned as a function of increasing (NH4)6Mo7O24 concentration at fixed ODP concentration. The chemical structure of the ODP/POM hybrids was characterized by (1)H, (31)P, and (95)Mo NMR spectroscopy. Heteronuclear (31)P DOSY (diffusion- ordered NMR spectroscopy) and molecular mechanics (MM) calculations were applied to determine the size and shape of the nanosized hybrids generated at various ODP/POM ratios. For this purpose, the structures of ODP/POM hybrids with variable numbers of ODP and POM units were optimized by MM and then approximated as cylinder-shaped objects by using a recently described mathematical algorithm. The thus-obtained cylinder length and diameter were further used to calculate the expected diffusion coefficients of the ODP/POM hybrids. Comparison of the calculated and experimentally determined diffusion coefficients led to the most probable ODP/POM hybrid length for each sample composition. The (31)P DOSY results show that the length of the hybrids increases with increasing POM concentration and reaches a maximum corresponding to an average of 8 ODP/7 POM units per chain at a sample composition of 20 mM ODP and 14 mM POM. With excess POM, above the latter concentration, the formation of shorter-chain hybrids terminated by Mo7 clusters at one or both ends was evidenced on further increasing the POM concentration. The results demonstrate that the combination of (31)P DOSY and MM, although virtually unexplored in POM chemistry, is a powerful innovative strategy for the detailed characterization of nanosized organic-inorganic POM-based hybrids in solution.


PMID: 24729454

DOI: 10.1002/chem.201304969

Other references

Ishiko, J.; Inagaki, C.; Takaori, S., 1983: Effects of diazepam, nitrazepam and brotizolam on dopamine turnover in the olfactory tubercle, nucleus accumbens and caudate nucleus of rats. Japanese Journal of Pharmacology 33(3): 706-708

Dolezel, J.; Lucretti, S.; Macas, J., 1995: Flow cytometric analysis and sorting of plant chromosomes. Recent work is reviewed under the headings: preparation of chromosome suspensions; flow cytometric analysis; application of flow karyotyping and chromosome sorting; and conclusions.

Vader, W., 1986: Menigratopsis svennilssoni (Amphipoda, Lysianassoidea) found in northern Norway. Fauna Norvegica Series A: 7: 47

Sobieski J.; Bielawski J., 1982: Gramicidin a and valinomycin induced permeability of potassium chloride in pig erythrocyte membranes. Gramicidin A and valinomycin are soluble in ethanol. When the ethanol concentration diminishes below 50% both antibiotics are inactivated. Inactivation in aqueous medium is a slow process lasting for 5 h. The dependence of ionophore-induced erythr...

Ottaviano, G.; Doro, D.; Marioni, G.; Mirabelli, P.; Marchese-Ragona, R.; Tognon, S.; Marino, F.; Staffieri, A., 2006: Extranodal Rosai-Dorfman disease: involvement of eye, nose and trachea. Rosai-Dorfman disease (RDD) is a rare non-neoplastic histiocytic proliferative disorder characterized by painless lymphadenopathy. Extranodal lesions frequently occur in the head and neck regions. We report the clinical and histological features o...

Lamba D.; Burden C.; Mackie W.; Sheldrick B., 1986: The crystal and molecular structure of alpha laminaribiose octaacetate. The crystal and molecular structure of octa-O-acetyl-.alpha.-laminaribiose is compared with those of disaccharides, and their acetylated derivatives, related to polysaccharides of the laminarin and curdlan type. Marked differences are found in the...

Lin Chunming, 1996: Recognition of the last glaciation incised valley and its significance in biogas prospecting as exemplified by the Qiangtangjiang incised valley. The last glaciation incised valley was reconstructed based on the following: (1) The valley floor is the surface of the erosion unconformity as a result of erosion and dissection of the river during sea-level flooding land sediment deposited in th...

Matis, P.; Schmiederer, H.L., 1955: Experimental studies on aminoacetic acid-electrolyte complex. Arzneimittel-Forschung 5(1): 30-32

Graeter, Alb., 1903: Die Copepoden der Umgebung Basels. Revue Suisse de Zoologie, XI 419-541

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