The unique properties of fullerenes have raised the interest of using them for biomedical applications. Within this framework, the interactions of fullerenes with proteins have been an exciting research target, yet little is known about how native proteins can bind fullerenes, and what is the nature of these interactions. Moreover, though some proteins have been shown to interact with fullerenes, up to date, no crystal structure of such complexes was obtained. Here we report docking studies aimed at examining the interactions of fullerene in two forms (C60 nonsubstituted fullerene and carboxyfullerene) with four proteins that are known to bind fullerene derivatives: HIV protease, fullerene-specific antibody, human serum albumin, and bovine serum albumin. Our work provides docking models with detailed binding pockets information, which closely match available experimental data. We further compare the predicted binding sites using a novel multiple binding site alignment method. A high similarity between the physicochemical properties and surface geometry was found for fullerene's binding sites of HIV protease and the human and bovine serum albumins.

The preparation and characterization of the stable human serum albumin (HSA)-C3 isomer of tris-malonic acid [C60]fullerene complex is reported. Other than the anti-fullerene antibody, a stable protein-fullerene complex with a native protein has never been observed. This study may provide valuable answers to the growing concern regarding the effects of carbonaceous nanomaterials on human health on one hand and, on the other, may lead to the development of novel antioxidant therapeutic agents, radiopharmaceuticals, and components for bioelectronic devices.

Concern is growing about the potential impact of human exposure to carbonaceous nanomaterials (such as fullerenes) in the environment. A valid biological study of how native biomolecules interact with nanomaterials at the molecular level in physiological conditions requires the preservation of their physicochemical properties, yet most investigations rely on the use of modified fullerene conjugates or aggregates. We report the formation of a stable, water-soluble, well-defined complex between a single molecule of pristine C(60)-fullerene and a native protein, bovine serum albumin protein (BSA), with the normal three-dimensional structure of BSA preserved. The ability to produce a pristine C(60)-fullerene-BSA hybrid at a physiological pH range lays a solid foundation for studying carbonaceous materials, biodelivery systems, and transport mechanisms and for characterizing the potential effects of nanomaterials on wildlife and human health, both in vitro and in vivo.

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A method of synthesizing stable chiral Ag nanoparticles inside a natural mucin glycoprotein is demonstrated. The reaction is carried out without the help of an external reducing agent, by utilizing the reducing properties of the host mucin. A chiral spectrum is detected in the visible range, indicating the formation of a new type of chiral Ag nanoparticles-containing biomaterial.

In recent years, the exposure of biological systems to various nanomaterials has become an issue of great public concern. Although living organisms have arrays of biological defense mechanisms against exposure to exogenous compounds, the biochemical mechanisms allowing various nanomaterials to enter the body are not well understood. A unique example of a typical mucosal glycoprotein capable of binding and solubilizing nanomaterials in physiological solution is provided, suggesting a possible route for entry into biological systems.

A novel methodology for the evaluation of receptor arrangement in structurally flexible anion chemosensors was developed and applied to map the binding site of a new pseudocyclic tristhiourea chemosensor (6). The syntheses of 6 and related macrocyclic chemosensor 10 (a model of the folded monomeric structure of 6) are reported. Both chemosensors were evaluated by titration with a variety of structurally different anions in CH3Cl and DMSO, showing a common preference for F-, CH3CO2-, and H2PO4-. However, within this group of anions, the binding patterns of the chemosensors differed, indicating dissimilarity in the arrangement of the binding sites of 6 and 10.

In recent years, research in the field of protein‐based fibrils gained a great attention due to use of these materials as building blocks for construction of functional synthetic biofilms. Yet, efficient and general methodology for preparation of orderly‐doped fibrils with desired properties, made of protein‐dopant/ligand complexes, still remains a significant challenge. In this manuscript, it is demonstrated that the β‐lactoglobulin (β‐Lg) protein can form stable and well‐defined complexes with linear retinoic acid, discotic protoporphyrine IX and spherical carboxyfullerene ligands (dopants). Upon heating these β‐Lg complexes under acidic conditions, formation of orderly‐doped fibrils, which partially preserved ligand‐specific stoichiometries and modes of binding (of the parent protein‐dopant complexes), is observed. These results present a new synthetic methodology, which complements other reported approaches for preparation of the protein‐based doped fibrils, by surface functionalization and by post‐assembly modulation techniques. A combination of ordered self‐assembly nano‐structures, with chemical versatility of the orderly‐doped protein‐based fibrils, represents a new method for construction of novel multifunctional materials in a bottom‐up fashion. Preparation of composite β‐Lg‐complex fibrils by the co‐assembly process, using β‐Lg building blocks that already incorporate various organic ligands inside, is unprecedented.