Hollow Periodic Mesoporous Organosilica Nanoparticles (HPMO-NPs) with a controlled core cavity and a Periodic Mesoporous Organosilica (PMO) shell have been synthesized using a dual templating approach. A dense silica hard template is firstly prepared following classical Stöber sol-gel protocol. The hybrid silica shell is then deposited through a one-pot strategy by the co-condensation of the organosilane precursor with surfactant. HPMO-NPs are then obtained after the final etching steps of the hard and soft templates. In this work, we demonstrate that this strategy can be applied to synthesize:a/ HPMO-NPs with controlled diameter sizes ranging from 600 nm to 40 nm, b/ HPMO-NPs with various shell composition by adjusting the nature of the organosilane precursor, c/ Yolk shell structures with a functional central nanoparticle. We will detail the structural properties of the HPMO-NPs using a multi-scale experimental study at the various stages of synthesis, highlighting the role of mesoporosity and the structural organization of the PMO shell on its properties.Finally, in view of medical applications, we will also present endocytosis and biocompatibility preliminary results.

Understanding the techno-functional properties of underutilized plant -based proteins, such as potato proteins, is essential in the context of the development of alternative proteins and plant -based foods. In this study, the aggregation kinetics of patatin-rich dispersions at two concentrations (1% and 4% w/w) and pH levels (6 and 7) were evaluated and compared under two physical processes: heat treatment (45 C-degrees, 50 C-degrees, 55 C-degrees) and high hydrostatic pressure (400 MPa, 600 MPa). Distinct patterns in patatin aggregation were observed based on the processing and physicochemical conditions. Under all processing conditions, larger aggregates were formed at pH 6. Heat treatment led to either a slow or rapid gradual increase in aggregate size at the different pH and protein concentrations, while high -pressure -generated nanoaggregates displayed pH and pressure -level dependent kinetic behaviors. Some micro, sub -micron and nanoaggregates were then selected and characterized in terms of denaturation yield, molecular structure, and protein interactions. High-pressure treatment induced a significant reduction in protein intrinsic fluorescence intensity suggesting irreversible partial protein unfolding, irrespective of pressure or pH. The highest pressure level (600 MPa) led to significantly higher denaturation, regardless of pH. Similar trends in secondary structure modifications were observed for the different treatment conditions and were characterized by an increase in beta-sheet content and a reduction in alpha-helices. The structural changes in the high pressure -treated samples were particularly influenced by pH. This study provides a deeper understanding of potato protein behavior under different treatment conditions, which may contribute to the design of novel plant -based protein nanostructures.

Single walled carbon nanotubes (SWCNTs) have gained interest in the field of nanoscaleconfinement of the fluids, with a variety of unexpected phenomena such as spontaneous filing,frictionless mas transport, unusual phase diagram, etc. (1). The majority of these phenomenaremains unexplored and requires experimental confirmation. In addition, the field requiresa sensitive method to carry out measurement in the level of individual and SWCNT, as theconfinement is sensitive to the tube diameter. On the other hand, the intrinsic and extrinsicelectronic properties of the SWCNT is shown to be sensitive to the diameter, defects, doping,adsorbates, and environment via SWCNT field effect transistors (SWCNT-FET) (2,3).In this contribution, we show that the electronic response of the individual SWCNT based fieldeffect transistor is an essential tool to study water-CNT coupling mechanism and accuratelyidentify the impact of water confined inside the nanotube. We investigate the charge transfercharacteristics of the SWCNT-FET, while exposing several individual SWCNT first unopened,then opened to different environment, such as ambient air, air humidity, vacuum and currentannealing under vacuum. We demonstrate that it is possible to assign CNT doping as the mainmechanism behind water-CNT coupling, and distinguish between water adsorbed outside ofthe nanotube from confined inside. Precisely, we found that putting the device under secondaryvacuum, after exposing to air humidity, shift the gate voltage neutrality point of opened SWCNTtowards more negative values, however, the secondary vacuum has no effect on the same SWCNTwhen it was closed. We also demonstrate that this behavior is independent CNT metallicity,assuming that the nanotube’s surface has been pre-cleaned using current annealing. We willalso discuss the water adsorption and desorption kinetics and dynamics.Our findings open up the possibility of using CNTFET to address long-standing issues in thenanofluidic community regarding the behavior of water confinement at the nanoscale, and alsoto use them for reliable, sensitive, and selective chemical and biological sensors.

Poly(N-isopropylacrylamide) (PNIPAM) is one of the most well studied thermoresponsive polymers and its microgels undergo a reversible volume phase transition (VPT) at temperatures close to that of the human body. Coupling this property with the unique optical properties of single-walled carbon nanotubes (SWCNT) in the near infrared (NIR) leads to interesting nanohybrids that could be used as multi-responsive sensors/actuators for biological applications.We show the synthesis of thermoresponsive SWCNT/PNIPAM hybrids using two different non-covalent strategies, preserving the nanotube optical properties such as fluorescence. The first strategy involves the dispersion of the SWCNT in water with sodium dodecyl sulfate (SDS), and subsequent in situ synthesis of PNIPAM microgels inside the SDS coatings around the nanotubes. The second strategy starts with modifying the nanotubes with a pyrene derivative, which in turn is used as the starting point for the in situ polymerization of the PNIPAM microgels, thus ensuring that the polymer grows around the nanotubes. In both cases, we obtain hybrids showing a phase transition at temperatures close to that of the human body, with the absorption and fluorescence spectra of the hybrids in the NIR changing in response to the changing dielectric environment. These systems could be used as actuators/sensors in biological systems.

ContextSingle-wall carbon nanotubes (SWCNT) dispersed in water with the help of sodium dodecyl sulfate (SDS) surfactants exhibit a temperature dependent near infrared (NIR) exciton spectrum. Due to their biocompatibility and NIR spectrum falling within the transparent window for biological tissue, SWCNTs hold potential for sensing temperature inside cells. Here, we seek to elucidate the mechanism responsible for this temperature dependence, focusing on changes in the water coverage of the SWCNT as the surfactant structure changes with temperature. We compare optical absorption spectra in the UV–Vis-IR range and fully atomistic molecular dynamics (MD) simulations. The observed temperature dependence of the spectra for various SWCNTs may be attributed to changes in the dielectric environment and its impact on excitons. MD simulations reveal that the adsorbed SDS molecules effectively shield the SWCNT, with ~ 70% of water molecules removed from the first two adlayers; this coverage shows a modest temperature dependence. Although we are not able to directly demonstrate how this influences the NIR spectrum, this represents a potential pathway given the strong influence of the water environment on the excitons in SWCNTs.MethodsOptical absorption measurements were carried out in the UV–Vis-NIR range using a Varian Cary 5000 spectrophotometer in a temperature-controlled environment. PeakFit™ v. 4.06 was used as peak-fitting program in the spectral range 900–1400 nm (890–1380 meV) as a function of the temperature. Fully atomistic molecular dynamics simulations were conducted using the NAMD2 package. The CHARMM force field comprising two-body bond stretching, three-body angle deformation, four-body dihedral angle deformation, and nonbonded interactions (electrostatic and Lennard–Jones 6–16 potentials) was employed.

Recent advancements in materials science have shed light on the potential of exploring hierarchical assemblies of molecules on surfaces, driven by both fundamental and applicative challenges. This field encompasses diverse areas including molecular storage, drug delivery, catalysis, and nanoscale chemical reactions. In this context, the utilization of nanotube templates (NTs) has emerged as promising platforms for achieving advanced one-dimensional (1D) molecular assemblies. NTs offer cylindrical, crystalline structures with high aspect ratios, capable of hosting molecules both externally and internally (Mol@NT). Furthermore, NTs possess a wide array of available diameters, providing tunability for tailored assembly. This review underscores recent breakthroughs in the field of Mol@NT. The first part focuses on the diverse panorama of structural properties in Mol@NT synthesized in the last decade. The advances in understanding encapsulation, adsorption, and ordering mechanisms are detailed. In a second part, the review highlights the physical interactions and photophysics properties of Mol@NT obtained by the confinement of molecules and nanotubes in the van der Waals distance regime. The last part of the review describes potential applicative fields of these 1D heterostructures, providing specific examples in photovoltaics, luminescent materials, and bio-imaging. A conclusion gathers current challenges and perspectives of the field to foster discussion in related communities.

Despite 15 years of extensive investigation, the fabrication and study of nanofluidic devices that incorporate a single carbon nanotube (CNT) still represents a remarkable experimental challenge. In this study, we present the fabrication of nanofluidic devices that integrate an individual single-walled CNT (SWCNT), showcasing a notable reduction in noise by 1 -3 orders of magnitude compared to conventional devices. This achievement was made possible by employing high dielectric constant materials for both the substrate and the CNT-covering layer. Furthermore, we provide a detailed account of the crucial factors contributing to the successful fabrication of SWCNT-based nanofluidic devices that are reliably leak-free, plug-free, and long-lived. Key considerations include the quality of the substrate-layer interface, the nanotube opening, and the effective removal of photoresist residues and trapped microbubbles. We demonstrate that these devices, characterized by a high signal-tonoise ratio, enable spectral noise analysis of ionic transport through an individual SWCNT, thus showing that SWCNTs obey Hooge's law in 1/ f at low frequencies. Beyond advancing our fundamental understanding of ion transport in SWCNTs, these ultralow-noise measurements open avenues for leveraging SWCNTs in nanopore sensing applications for single-molecule detection, offering high sensitivity and identification capabilities.