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Background Huperzine A (HupA) is a selective acetylcholinesterase inhibitor used to treat Alzheimer’s disease. The existing dosage of HupA lacks brain selectivity and can cause serious side effects in the gastrointestinal and peripheral cholinergic systems. Purpose The aim of this study was to develop and characterize a HupA nanoemulsion (NE) and a targeted HupA-NE modified with lactoferrin (Lf) for intranasal administration. Methods The NE was formulated using pseudo-ternary phase diagrams and optimized with response surface methodology. Particle size distribution and zeta potential were evaluated, and transmission electron microscopy was performed. We investigated the transport mechanisms of HupA-NEs into hCMEC/D3 cells, an in vitro model of the blood-brain barrier. HupA-NE, Lf-HupA-NE, and HupA solution were intranasally administered to rats to investigate the brain-targeting effects of these formulations. A drug targeting index (DTI) was calculated to determine brain-targeting efficiency. Results Optimized HupA-NE had a particle size of 15.24±0.67 nm, polydispersity index (PDI) of 0.128±0.025, and zeta potential of −4.48±0.97 mV. The composition of the optimized HupA-NE was 3.00% isopropyl myristate (IPM), 3.81% Capryol 90, and 40% Cremophor EL + Labrasol. NEs, particularly Lf-HupA-NE, were taken up into hCMEC/D3 cells to a greater extent than pure drug alone. Western blot analysis showed that hCMEC/D3 cells contained P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and multidrug resistance associated protein 1 (MRP1) transporters. The likely mechanisms resulting in higher NE transport to the brain were uptake by specific transporters and transcytosis. In vivo, intranasal Lf-HupA-NE significantly enhanced drug delivery to the brain compared to HupA-NE, which was confirmed by differences in pharmacokinetic parameters. The DTI of Lf-HupA-NE (3.2±0.75) demonstrated brain targeting, and the area under the curve for Lf-HupA-NE was significantly higher than that for HupA-NE. Conclusion Lf-HupA-NE is a promising nasal drug delivery carrier for facilitating delivery of HupA to the central nervous system., Video abstract Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use: https://youtu.be/EpqKwDyguVs

International audience; The electrocaloric effect in lead-free BaTi 1Àx Sn x O 3 (BTSn, x ¼ 0.08, 0.105, and 0.14) ferroelectric ceramics was studied by using an indirect method. It was found that the largest electrocaloric response could be achieved in BTSn with x ¼ x QP ¼ 0.105 near room temperature with an adiabatic temperature change DT of 0.61 K and an electrocaloric strength DT=DE of 0.31 K mm kV À1 , under a modest electric field DE of 20 kV cm À1 , which is comparable with the best values reported in lead-free materials. These enhanced values are attributed to the multiphase (four phases) coexistence at x ¼ x QP corresponding to the quasi-quadruple point composition. V C 2014 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4895615] There has been a recent upsurge in research on electro-caloric (EC) materials since the discovery of giant EC effect in PbZr 0.95 Ti 0.05 O 3 thin films in 2006. 1 The EC effect, defined as the reversible adiabatic temperature change and/or isothermal entropy change of a dielectric material upon the application or removal of an external electric field, may find promising applications in realizing innovatively eco-friendly cooling devices. 1–5 To achieve high EC performances near room temperature (RT), the use of phase transitions is revealed to be a powerful tool since the largest EC effect usually occurs near the phase transition. In addition, in order to tune the properties of EC materials, various approaches have been proposed, which include, but are not restricted to, tailoring the thickness of an EC film, 1,6–9 doping, 10 changing the anisotropy/texture of the material, 11 applying a stress field 12,13 or a hydrostatic pressure, 14 improving the material capability to enhance the electrical breakdown strength