Elucidating the binding mode of carboxylate-containing ligands to gold nanoparticles (AuNPs) is crucial to understand their stabilizing role. A detailed picture of the three-dimensional structure and coordination modes of citrate, acetate, succinate and glutarate to AuNPs is obtained by C andNa solid-state NMR in combination with computational modelling and electron microscopy. The binding between the carboxylates and the AuNP surface is found to occur in three different modes. These three modes are simultaneously present at low citrate to gold ratios, while a monocarboxylate monodentate (1κO) mode is favoured at high citrate:gold ratios. The surface AuNP atoms are found to be predominantly in the zero oxidation state after citrate coordination, although trace amounts of Au are observed. Na NMR experiments show that Na ions are present near the gold surface, indicating that carboxylate binding occurs as a 2e L-type interaction for each oxygen atom involved. This approach has broad potential to probe the binding of a variety of ligands to metal nanoparticles.

Metal-organic framework (MOF) nano particles are a class of promising porous nano materials for biomedical applications. Owing to its high loading potential and pH-sensitive degradation, most promising of the MOFs is the zeolitic imidazolate crystal framework (ZIF-8), a progressive useful material for small molecule distribution. Doxorubicin (DOX), designated as a classical drug, was jobwise entrapped in ZIF-8 nano particles. ZIF-8 nano particles, as a novel carrier, were used to monitor the release of the anticancer drug DOX and prevent it from dissipating before reaching its goal. ZIF-8 nano particles with encapsulated DOX (DOX@ZIF-8) can be synthesized in a single pot by incorporation of DOX into the reaction mixture. MOFs and the designed drug delivery (DOX@ZIF-8) system were characterized by Fourier transfer infrared, scanning electron microscopy, N 2 sorption isotherm and X-ray diffraction. The impact of MOFs and the engineered drug delivery system on the viability of human breast and liver cancer cell lines was evaluated. The loaded drug was released at pH 5 faster than at pH 7.4. The nano particles of ZIF-8 showed low cytotoxicity, while DOX@ZIF-8 showed high cytotoxicity to HepG-2 and MCF-7 cells compared with free DOX at the equivalent concentration of DOX of >12.5 μg/ml. These findings indicate that DOX@ZIF-8 nano particles are a promising method for the delivery of cancer cells to drugs. Furthermore, ZIF-8, DOX and encapsulated DOX@ZIF-8 compounds were screened for their potential antibacterial activities against pathogenic bacteria compared with standard antibiotics by the agar well diffusion technique. The results demonstrate that the DOX@ZIF-8 exhibits a strong inhibition zone against Gram-negative strains (Escherichia coli) in comparison with the reference drug gentamycin. The docking active site interactions were evaluated to predict the binding between DOX with the receptor of breast cancer 3hb5-oxidoreductase and liver cancer 2h80-lipid binding protein for anticancer activity.

Gold nanoparticles (Au NPs) of different sizes were supported on fibrous silica nanospheres (KCC‐1) by various methods. The size and the location of the Au NPs on the support were found to depend on the preparation method. The KCC‐1‐supported Au NPs were thoroughly characterized by using HR‐TEM, XRD, X‐ray photoelectron spectroscopy, UV, and Brunauer–Emmett–Teller surface area measurements and were applied in catalysis for the oxidation of CO. The catalytic performance is discussed in relation to the morphological properties of KCC‐1.

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In the current study, biocompatible and biodegradable blends based on poly(vinyl alcohol) nanoparticles - PVAn mixed with either chitosan (Ch) or starch (St) - were prepared and investigated as nanoabsorbents for oil elimination from wastewater. The use of water/dimethyl sulfoxide (DMSO) as a mixed solvent is the key factor for preparing aggregated PVAn, which is further mixed with Ch or St. Nanoblends were applied as oil absorbents, and the results showed that PVAn/St possess high adsorption capacity than PVAn/Ch and PVAn. The maximum sorption capacities (q) of the PVAn/Ch sorbents for hydraulic oil, kerosene, and toluene were 33.6, 73.96, and 93.1g/g, respectively. The absorbed oil could be rapidly recovered by simple mechanical squeezing and reused without any other modification. The blends showed excellent reusability and could be reused for at least 10 times with minimal losses. The current study demonstrates the application of these blends as an ideal alternative sorbent for oil spillage cleanup.

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