Anales RANF

Nannocannabinoids for brain tumor drug delivery @Real Academia Nacional de Farmacia. Spain 205 adsorption at the amphiphilic interface. Overall, the size distribution features of both types of fluorescently-labeled LNCs were analogous. As shown in Figure 2, the encapsulation of the fluorescent dyes did not alter the size of blank LNCs (20 nm and 40 nm, respectively). Conversely, the adsorption of CBD on fluorescently-labeled LNCs increased their particle size from 20 to 40 nm and from 40 to 55-60 nm. This increase followed an inverse size-related pattern: a 100%-increase for the smaller LNCs versus a 48%-increase for the bigger ones. The higher specific surface area of the smaller LNCs can account for this trend observed upon CBD functionalization. Moreover, the zeta potential profiles of CBD-adsorbed LNCs were noticeably sharpened in comparison with those of blank LNCs (Figure S1). These profiles support the superficial location of the adsorbed CBD. Figure 2: Average volume diameter of the different LNCs used to assess the BBB and glioma targeting ability: blank LNCs (orange), non-functionalized fluorescently-labeled LNCs (DiO: gold; DiD: navy blue) and CBD- adsorbed fluorescently-labeled LNCs (DiO: turquoise, DiD: green). For each formulation, there exist a smaller- sized (squared fill pattern) and a bigger-sized (striped fill pattern) counterpart. The experimental design to assess the BBB and glioma targeting ability of LNCs was as follows. On the one hand, as the cell internalization mechanisms may follow a size- dependent pattern, the role played by particle size in the targeting properties has been assessed separately in undecorated and in CBD-adsorbed fluorescently-labeled LNCs. On the other hand, as the increase of particle size due to CBD adsorption within the 20-60 nm interval represents a higher percentage increase than in the most widely explored 100-nm range, should particle size play a statistically significant role in the targeting properties, the influence of CBD-decoration will be then evaluated for equally-sized LNCs to maintain the size variable constant. The BBB-targeting ability has been evaluated through uptake and permeability experiments conducted with the human brain endothelial cell line hCMEC/D3. The results obtained with the in vitro cell-based BBB model have also been validated with in vivo biodistribution data in healthy mice. The quantitative analysis of the in vitro BBB-targeting ability is shown in Figure 3. Results consistently demonstrated a significantly higher BBB-targeting effect for smaller LNCs (1.8-fold for undecorated LNCs, p < 0.01 and 2.0-fold for CBD-adsorbed LNCs, p<0.01). Given the influence of particle size on the BBB targeting ability, the role played by CBD-adsorption was then assessed from a comparison of equally-sized LNCs. The adsorption of CBD on LNCs enhanced by 1.4-fold (p < 0.05) the BBB targeting ability of their undecorated equally-sized counterparts. The 3D reconstructions from the Z-stacks of the images taken by confocal microscopy evidenced qualitatively a perinuclear location of the LNCs within the hCMEC/D3 cells (Figure 4).