On high purity fullerenol obtained by combined dialysis and freeze-drying method with its morphostructural transition and photoluminescence

Unlocking cellular barriers: silica nanoparticles and fullerenol conjugated cell-penetrating agents for enhanced intracellular drug delivery

The limited delivery of cargoes at the cellular level is a significant challenge for therapeutic strategies due to the presence of numerous biological barriers. By immobilizing the Buforin II (BUF-II) peptide and the OmpA protein on magnetite nanoparticles, a new family of cell-penetrating nanobioconjugates was developed in a previous study. We propose in this study to extend this strategy to silica nanoparticles (SNPs) and silanized fullerenol (F) as nanostructured supports for conjugating these potent cell-penetrating agents. The same molecule conjugated to distinct nanomaterials may interact with subcellular compartments differently. On the obtained nanobioconjugates (OmpA-SNPs, BUF-II-PEG12-SNPs, OmpA-F, and BUF-II-PEG12-F), physicochemical characterization was performed to evaluate their properties and confirm the conjugation of these translocating agents on the nanomaterials. The biocompatibility, toxicity, and internalization capacity of nanobioconjugates in Vero cells and THP-1 cells were evaluated in vitro. Nanobioconjugates had a high internalization capacity in these cells without affecting their viability, according to the findings. In addition, the nanobioconjugates exhibited negligible hemolytic activity and a low tendency to induce platelet aggregation. In addition, the nanobioconjugates exhibited distinct intracellular trafficking and endosomal escape behavior in these cell lines, indicating their potential for addressing the challenges of cytoplasmic drug delivery and the development of therapeutics for the treatment of lysosomal storage diseases. This study presents an innovative strategy for conjugating cell-penetrating agents using silica nanoparticles and silanized fullerenol as nanostructured supports, which has the potential to enhance the efficacy of cellular drug delivery.

Multistep Transformation from Amorphous and Nonporous Fullerenols to Highly Crystalline Microporous Materials

The structural and morphological properties of fullerenols upon exposure to heat treatment have yet to be understood. Herein, the temperature-driven structural and morphological evolutions of fullerenols C₆₀ (OH) and C₇₀ (OH) were investigated. In situ spectroscopic techniques, such as variable-temperature X-ray diffraction and coupled thermogravimetric Fourier-transform infrared analysis, were used to elucidate the structural transformation mechanism of fullerenols. Both fullerenols underwent four-step structural transformation upon heating and cooling, including amorphous-to-crystalline transition, thermal expansion, structural compression, and new crystal formation. Compared to the initially nonporous amorphous fullerenol, the crystalline product exhibited microporosity with a surface area of 114 m²  g^-1 and demonstrated CO₂ sorption capability. These findings show the potential of fullerene derivatives as adsorbents.

Quaternary Ammonium Salts of Iminofullerenes: Fabrication and Effect on Seed Germination

In this study, novel water-soluble quaternary ammonium salts of iminofullerenes (IFQA) were synthesized by nitrene chemistry in combination with quaternization and identified as [C₆₀(NCH₂CH₂NH₃⁺·CF₃COO^-)₄·10H₂O]_n by various spectroscopies. Maize and Arabidopsis seeds were used to test the bioactivity of IFQA in seed germination. Compared with the control, maize seed exposure to 50 mg/L IFQA (normal: 73.1% vs 58.7%; drought: 66.7% vs 50.0% at the second day) and Arabidopsis seed exposure to 20 mg/L IFQA (normal: 77.5% vs 58.8%; drought: 63.3% vs 36.7% at the second day) had higher germination rates and quicker germination. The results of two-dimensional gel electrophoresis combined with mass spectroscopy showed that the abundance of 21 proteins in embryo proteome of maize seeds was significantly changed (>1.5 fold). The downregulated six storage proteins and upregulated four proteins induced by IFQA for energy production and sugar metabolism indicated a faster metabolic activity of maize seed germination. The upregulated eight stress-related proteins and antioxidant enzymes suggested that the role of IFQA was to activate the metabolic processes in seed germination and also increase seed stress response. The results provide important information to understand the mechanism of seed germination enhancement by carbon nanomaterials.