Direct Visualization of Dye and Oligonucleotide Diffusion in Silica Filaments with Collinear Mesopores

The diffusion dynamics of terrylene diimide (TDI) dye molecules and dye-labeled double-strand DNA were studied in micrometer long silica filaments containing collinear, oriented mesopores using single molecule fluorescence microscopy. TDI was used as a stable and hydrophobic probe molecule for single molecule structural analysis. We used template-free mesoporous silica filaments with 4 nm pore diameter and chemical functionalization with one or two types of trialkoxysilane groups to enhance the affinity between the host system and the guest molecules. Insights about the mesoporous structure as well as the translational and orientational diffusion dynamics of the guest molecules observed along micrometer long trajectories could be obtained. Additionally, the stability of DNA oligomers (15 base pairs, bp, about 5.3 nm long) within the mesopores was examined, showing no degradation of the oligonucleotide upon incorporation into the mesopores. Diffusion of both guest molecules could be controlled by exposure to vapors of water or chloroform; the latter both induced a reversible on–off control of the translational movement of the molecules

Direct Visualization of Dye and Oligonucleotide Diffusion in Silica Filaments with Collinear Mesopores

The diffusion dynamics of terrylene diimide (TDI) dye molecules and dye-labeled double-strand DNA were studied in micrometer long silica filaments containing collinear, oriented mesopores using single molecule fluorescence microscopy. TDI was used as a stable and hydrophobic probe molecule for single molecule structural analysis. We used template-free mesoporous silica filaments with 4 nm pore diameter and chemical functionalization with one or two types of trialkoxysilane groups to enhance the affinity between the host system and the guest molecules. Insights about the mesoporous structure as well as the translational and orientational diffusion dynamics of the guest molecules observed along micrometer long trajectories could be obtained. Additionally, the stability of DNA oligomers (15 base pairs, bp, about 5.3 nm long) within the mesopores was examined, showing no degradation of the oligonucleotide upon incorporation into the mesopores. Diffusion of both guest molecules could be controlled by exposure to vapors of water or chloroform; the latter both induced a reversible on–off control of the translational movement of the molecules

Direct Visualization of Dye and Oligonucleotide Diffusion in Silica Filaments with Collinear Mesopores

The diffusion dynamics of terrylene diimide (TDI) dye molecules and dye-labeled double-strand DNA were studied in micrometer long silica filaments containing collinear, oriented mesopores using single molecule fluorescence microscopy. TDI was used as a stable and hydrophobic probe molecule for single molecule structural analysis. We used template-free mesoporous silica filaments with 4 nm pore diameter and chemical functionalization with one or two types of trialkoxysilane groups to enhance the affinity between the host system and the guest molecules. Insights about the mesoporous structure as well as the translational and orientational diffusion dynamics of the guest molecules observed along micrometer long trajectories could be obtained. Additionally, the stability of DNA oligomers (15 base pairs, bp, about 5.3 nm long) within the mesopores was examined, showing no degradation of the oligonucleotide upon incorporation into the mesopores. Diffusion of both guest molecules could be controlled by exposure to vapors of water or chloroform; the latter both induced a reversible on–off control of the translational movement of the molecules

Direct Visualization of Dye and Oligonucleotide Diffusion in Silica Filaments with Collinear Mesopores

The diffusion dynamics of terrylene diimide (TDI) dye molecules and dye-labeled double-strand DNA were studied in micrometer long silica filaments containing collinear, oriented mesopores using single molecule fluorescence microscopy. TDI was used as a stable and hydrophobic probe molecule for single molecule structural analysis. We used template-free mesoporous silica filaments with 4 nm pore diameter and chemical functionalization with one or two types of trialkoxysilane groups to enhance the affinity between the host system and the guest molecules. Insights about the mesoporous structure as well as the translational and orientational diffusion dynamics of the guest molecules observed along micrometer long trajectories could be obtained. Additionally, the stability of DNA oligomers (15 base pairs, bp, about 5.3 nm long) within the mesopores was examined, showing no degradation of the oligonucleotide upon incorporation into the mesopores. Diffusion of both guest molecules could be controlled by exposure to vapors of water or chloroform; the latter both induced a reversible on–off control of the translational movement of the molecules

Direct Visualization of Dye and Oligonucleotide Diffusion in Silica Filaments with Collinear Mesopores

The diffusion dynamics of terrylene diimide (TDI) dye molecules and dye-labeled double-strand DNA were studied in micrometer long silica filaments containing collinear, oriented mesopores using single molecule fluorescence microscopy. TDI was used as a stable and hydrophobic probe molecule for single molecule structural analysis. We used template-free mesoporous silica filaments with 4 nm pore diameter and chemical functionalization with one or two types of trialkoxysilane groups to enhance the affinity between the host system and the guest molecules. Insights about the mesoporous structure as well as the translational and orientational diffusion dynamics of the guest molecules observed along micrometer long trajectories could be obtained. Additionally, the stability of DNA oligomers (15 base pairs, bp, about 5.3 nm long) within the mesopores was examined, showing no degradation of the oligonucleotide upon incorporation into the mesopores. Diffusion of both guest molecules could be controlled by exposure to vapors of water or chloroform; the latter both induced a reversible on–off control of the translational movement of the molecules

Additional file 1 of Development of doped ZnO-based biomimicking and tumor-targeted nanotheranostics to improve pancreatic cancer treatment

Additional file 1. Doped and undoped NCs characterizations; Extracellular vesicles characterizations; Liposomes coating; Lipo-Lipo-pep-NCs nanoconstruct characterizations; Additional TEM images of the optimized EV-Lipo-pep-NCs nanoconstruct; Drug delivery expressed in percentage; Cellular uptake of biomimetic nanoconstruct in Pancreatic Cancer Cells: control experiments; Preliminary tests on cytotoxicity of the Lipo-Lipo-pep-NCs-Gem

A Chemometric Approach for the Sensitization Procedure of ZnO Flowerlike Microstructures for Dye-Sensitized Solar Cells

In this paper, a methodology for the streamlining of the sensitization procedure of flowerlike ZnO nanostructures for dye-sensitized solar cells (DSCs) is reported. The sensitization of ZnO surface with ruthenium-based complexes is a particularly critical process, since one has to minimize the dissolution of surface Zn atoms by the protons released from the dye molecules, leading to the formation of Zn²⁺/dye complexes. The fine-tuning of the experimental parameters, such as the dye loading time, the dye concentration, and the pH of the sensitizing solution, performed through a multivariate optimization by means of a chemometric approach, is here reported. The dye loading procedure was optimized using ZnO microparticles with nanostructured protrusions, synthesized by a simple and low-cost hydrothermal process. Mild reaction conditions were used, and wurtzite-like crystalline structure with a relatively high surface area was obtained once the reaction process was completed. After dispersion of ZnO flowerlike particles in an acetic acid-based solution, a 14 μm-thick ZnO layer acting as DSC photoanode was fabricated. The optimized sensitization procedure allowed minimizing the instability of ZnO surface in contact with acidic dyes, avoiding the formation of molecular agglomerates unable to inject electrons in the ZnO conduction band, achieving good results in the photoconversion efficiency. Moreover, the photoharvesting properties were further enhanced by adding <i>N</i>-methylbenzimidazole into the iodine-based liquid electrolyte. Such an additive was proposed here for the first time in combination with a ZnO photoelectrode, helping to reduce an undesired recombination between the photoinjected electrons and the oxidized redox mediator

Optimization of 1D ZnO@TiO₂ Core–Shell Nanostructures for Enhanced Photoelectrochemical Water Splitting under Solar Light Illumination

A fast and low-cost sol–gel synthesis used to deposit a shell of TiO₂ anatase onto an array of vertically aligned ZnO nanowires (NWs) is reported in this paper. The influence of the annealing atmosphere (air or N₂) and of the NWs preannealing process, before TiO₂ deposition, on both the physicochemical characteristics and photoelectrochemical (PEC) performance of the resulting heterostructure, was studied. The efficient application of the ZnO@TiO₂ core–shells for the PEC water-splitting reaction, under simulated solar light illumination (AM 1.5G) solar light illumination in basic media, is here reported for the first time. This application has had a dual function: to enhance the photoactivity of pristine ZnO NWs and to increase the photodegradation stability, because of the protective role of the TiO₂ shell. It was found that an air treatment induces a better charge separation and a lower carrier recombination, which in turn are responsible for an improvement in the PEC performance with respect to N₂-treated core–shell materials. Finally, a photocurrent of 0.40 mA/cm² at 1.23 V versus RHE (2.2 times with respect to the pristine ZnO NWs) was obtained. This achievement can be regarded as a valuable result, considering similar nanostructured electrodes reported in the literature for this application