Pancreatic cancer is one of the deadliest cancers with an increasing incidence due to a lack ofearly-stage diagnostics and effective treatment [1]. The RAS/RAF/ MAPK/CDK4 pathway is frequentlydysregulated in pancreatic cancer and CDK4 constitutes an attractive target since several drugs havebeen approved by the FDA to inhibit its activity: Abemaciclib, Ribociclib and Palbociclib [2,3] (Figure1) However these inhibitors are not efficient in monotherapy and have only been approved for breastcancer. In order to propose an efficient therapeutic strategy to target CDK4 in pancreatic cancer, wepropose to deliver Abemaciclib using carbon nanotubes.
Carbon nanotubes are promising materials for nanomedicine applications and especially fordrug delivery. [4] In this project, we adsorb Abemaciclib onto single-walled carbon nanotubes (SWNT)for delivery of the drug into pancreatic cancer cells. In order to study adsorption, we investigate thechanges in the optical signatures of SWNTs in the near-infrared (NIR) by coupling NIR absorption,photoluminescence and Raman spectroscopies. [5] Typical kinetic spectroscopic results, assigned tothe adsorption of Abemaciclib on SWNT, dispersed in water using carbomethylcellulose (CMC), arepresented in Figure 2. We discuss the results in terms of changes of the dielectric environment of thenanotubes, leading to modulation of their excitonic and optical properties. We have furtherinvestigated the inhibitory potential of SWNT-Abemaciclib on proliferation of PANC1 cells comparedto Abemaciclib alone and have determined the toxicthreshold of SWNT dispersed in CMC.

Poly(N-isopropyl acrylamide) (PNIPAM) is a thermo-responsive polymer which undergoes a reversible coil-to-globule transition in water at temperatures close to the human body temperature [1]. Consequently, PNIPAM-based microgels show a volume phase transition (VPT) under heating. Photo-responsive hybrid microgels have been prepared by incorporating gold nanoparticles in PNIPAM microgels [2]. The outstanding photo-thermal and optical properties of single-walled carbon nanotubes (SWNTs) make them promising candidates to prepare multi-responsive hybrid microgels. However, no thorough studies have been reported so far.
In this work, we report the preparation and properties of aqueous dispersions of PNIPAM/SWNTs hybrid microgels (Figure 1a). We study their structure by transmission electron microscopy and dynamic light scattering. We investigate their optical properties and changes when heated at the VPT by near infrared (NIR) absorption, Raman and photoluminescence (PL) spectroscopies [3]. Furthermore, we use optical microscopy (Figure 1b), light scattering and NIR Raman/PL spectroscopy to show that the VPT transition can be triggered by NIR photo-thermal excitation.

Density functional tight-binding calculations of the adsorption of OH − and other related diatomic anions on carbon nanotubes and graphene show that two adsorption states coexist: a physisorption state caused by Debye interactions, and a chemisorption state at shorter distances dominated by ionic-covalent interactions. For all anions, both adsorption energies scale linearly with the curvature of the carbon surface, and increase with decreasing anion polarizability but also, in metallic nanotubes, with chiral angle. At short distances, charge transfer modifies the attractive Debye forces into repulsive forces of the dipole-dipole type, tuning the strength of the chemisorption state, and may determine its existence and stability.

NaLa(SO4)2,H2O crystalline powder was obtained under hydrothermal conditions at 220°C. A coupled TGA/DTA experiment of NaLa(SO4)2,H2O exhibits a weight loss at 260°C corresponding to the dehydration and an endothermal peak at 774°C. To elucidate the transformation mechanism as a function of temperature, single crystals have been grown at 80°C, 300 and 800°C. For each phase, single crystals have been isolated and structure determination was performed. As already published, NaLa(SO4)2,H2O crystallizes in a P3121 space group. However, the dehydration at 260°C is not a simple loss of the water molecule but a radical change in the structure. The removal of the water molecules inside the tunnels formed by the framework leads to a change in the coordination of the LaO9 Lanthanum-based polyhedrons. The compound obtained after dehydration is a new triple sulfate of the formula Na3La(SO4)3 crystallizing in the R-3 space group (a = 14.0976(1) Å; c = 8.1267(1) Å) with LaO12 icosahedrons. Millimeter size single crystals of this new phase have been grown under hydrothermal conditions (300°C, 157 bars). After the endothermal peak at 774°C, Na3La(SO4)3 decomposes by forming the anhydrous double sulfate NaLa(SO4)2 crystallizing in the P-1 space group with LaO10 polyhedrons. The structure of the three (NaLa)-compounds at RT, 300°C and 800°C is compatible with the expected Raman signatures. Finally, a complete transformation of NaLa(SO4)2,H2O up to 800°C is proposed. After 1000°C, the compound decomposes chemically with a large weight loss.

The coaxial stacking of two single-wall carbon nanotubes (SWCNTs) into a double-wall carbon nanotube (DWCNT), forming a so-called one-dimensional van der Waals structure, leads to synergetic effects that dramatically affect the optical and electronic properties of both layers. In this work, we explore these effects in purified DWCNT samples by combining absorption, wavelength-dependent infrared fluorescence–excitation (PLE), and wavelength-dependent resonant Raman scattering (RRS) spectroscopy. Purified DWCNTs are obtained by careful solubilization that strictly avoids ultrasonication or by electronic-type sorting, both followed by a density gradient ultracentrifugation to remove unwanted SWCNTs that could obscure the DWCNT characterization. Chirality-dependent shifts of the radial breathing mode vibrational frequencies and transition energies of the inner and outer DWCNT walls with respect to their SWCNT analogues are determined by advanced two-dimensional fitting of RRS and PLE data of DWCNT and their reference SWCNT samples. This exhaustive data set verifies that fluorescence from the inner DWCNT walls of well-purified samples is severely quenched through efficient energy transfer from the inner to the outer DWCNT walls. Combined analysis of the PLE and RRS results further reveals that this transfer is dependent on the inner and outer wall chirality, and we identify the specific combinations dominant in our DWCNT samples. These obtained results demonstrate the necessity and value of a combined structural characterization approach including PLE and RRS spectroscopy for bulk DWCNT samples.

The need for efficient probing, sensing, and control of the bioactivity of biomolecules (e.g., albumins) has led to the engineering of new fluorescent albumins' markers fulfilling very specific chemical, physical, and biological requirements. Here, we explore acetone-derived polymer dots (PDs) as promising candidates for albumin probes, with special attention paid to their cytocompatibility, two-photon absorption properties, and strong ability to non-destructively interact with serum albumins. The PDs show no cytotoxicity and exhibit high photostability. Their pronounced green fluorescence is observed upon both onephoton excitation (OPE) and two-photon excitation (TPE). Our studies show that both OPE and TPE emission responses of PDs are proteinaceous environment-sensitive. The proteins appear to constitute a matrix for the dispersion of fluorescent PDs, limiting both their aggregation and interactions with the aqueous environment. It results in a large enhancement of PD fluorescence. Meanwhile, the PDs do not interfere with the secondary protein structures of albumins, nor do they induce their aggregation, enabling the PD candidates to be good nanomarkers for non-destructive probing and sensing of albumins.