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Monolayer of Hydrazine Facilitates the Direct Covalent Attachment of C60 Fullerene to a Silicon Surface.

ABSTRACT: The development of oxygen-free organic-inorganic interfaces has led to new schemes for the functionalization of silicon surfaces with nitrogen-based chemical groups. However, building layers of large structures directly on this functionalized surface has remained elusive. This work confirms the path to form a stable interface between silicon and buckminsterfullerene C60 based on covalent chemical bonds. The starting point for this modification is the hydrazine-reacted Si(111) surface with the diamine functionality, which is further reacted directly with the C60 molecules. The chemistry of this process is confirmed spectroscopically and microscopically and can be used to form organic-inorganic interfaces separated by a single layer of nitrogen.

SUBMITTER: Gao F

PROVIDER: S-EPMC5554729 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Monolayer of Hydrazine Facilitates the Direct Covalent Attachment of C<sub>60</sub> Fullerene to a Silicon Surface.

Gao Fei F Teplyakov Andrew V AV

Langmuir : the ACS journal of surfaces and colloids 20170213 35

The development of oxygen-free organic-inorganic interfaces has led to new schemes for the functionalization of silicon surfaces with nitrogen-based chemical groups. However, building layers of large structures directly on this functionalized surface has remained elusive. This work confirms the path to form a stable interface between silicon and buckminsterfullerene C<sub>60</sub> based on covalent chemical bonds. The starting point for this modification is the hydrazine-reacted Si(111) surface ...[more]

PMID: 28157324

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Project description:The human body contains 60-70% water, depending on age. As a body fluid, it is not only a medium in which physical and chemical processes take place, but it is also one of the active mediators. Water is the richest substance with non-covalent hydrogen bonds. Water molecules, by themselves (in vacuum), are diamagnetic but when organized into clusters, they become diamagnetic or paramagnetic. Also, biomolecules (DNA, collagen, clathrin, and other proteins) have non-covalent hydrogen bonds in their structure. The interaction, as well as signal transmission, between water and biomolecules is achieved through the vibrations of covalent and non-covalent hydrogen bonds, which determine the state and dynamics of conformational changes in biomolecules. Disruptive conformational changes in biomolecules, cells, and tissues lead to their dysfunctionality, so they are a frequent cause of many disorders and diseases. For example, the rearrangement of hydrogen bonding due to mitochondrial disease mutation in cytochrome bc1 disturbs heme bH redox potential and spin state. In order to prevent and repair the dysfunctional conformational changes, a liquid substance was developed based on the second derivative of the C60 molecule (SD-C60), which has classical and quantum properties. The characterization of SD-C60 by UV-VIS-NIR, FTIR, TEM, and AFM/MFM was performed and it is shown that SD-C60 water layers generate vibrations with near-zero phase dispersion which are transmitted through Fibonacci's water chains to biomolecules. In comparison with previously published SD-C60 derivate (3HFWC, size until 10 nm, and 1-5 water layers), the improved formulation (3HFWC-W, size 10-25 nm, and 6-9 water layers) showed multiplied cytotoxic activity against melanoma cell lines of different aggressiveness. Apart from this, the mode of action was preserved and based on an induction of senescence rather than cell death. Importantly, high selectivity towards malignant phenotypes was detected. Observed effects can be ascribed to a machinery of hydrogen bonds, which are generated in SD-C60 and transmitted through water to biomolecules. This approach may open a new field in science and healthcare-a "water-based nanomedicine".

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Dataset Information

Monolayer of Hydrazine Facilitates the Direct Covalent Attachment of C60 Fullerene to a Silicon Surface.

Publications

Monolayer of Hydrazine Facilitates the Direct Covalent Attachment of C<sub>60</sub> Fullerene to a Silicon Surface.

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