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Polymeric micelles self-assembled from cholesterol-conjugated poly(ethylene glycol) (PEG) and anchored with transcriptional activator TAT peptide (TAT-PEG-b-Col) were fabricated for delivery of antibiotics across the blood-brain barrier (BBB). Ciprofloxacin, which demonstrated a high bactericidal effect, was efficiently loaded into the micelles by a membrane dialysis method. The ciprofloxacin-loaded micelles were characterized via dynamic light scattering and SEM. The micelles were spherical in nature, having an average diameter of smaller than 180 nm. Sustained release of ciprofloxacin was achieved over 6 h in phosphate-buffered saline (pH 7.4) at 37 degrees C. Confocal laser scanning microscopy reveals that the uptake of Fluorescein 5-isothiocyanate (FITC)-loaded TAT-PEG-b-Col micelles by human astrocytes was much higher than that of free FITC. Animal studies proved that these micelles crossed the BBB and entered the brain. The TAT-conjugated micelles may be used to deliver antibiotics across the BBB for treatment of brain infections.

Ferroelectric materials owning a polymorphic nanodomain structure usually exhibit colossal susceptibilities to external mechanical, electrical, and thermal stimuli, thus holding huge potential for relevant applications. Despite the success of traditional strategies by means of complex composition design, alternative simple methods such as strain engineering have been intensively sought to achieve a polymorphic nanodomain state in lead-free, simple-composition ferroelectric oxides in recent years. Here, a nanodomain configuration with morphed structural phases is realized in an epitaxial BaTiO 3 film grown on a (111)-oriented SrTiO 3 substrate. Using a combination of experimental and theoretical approaches, it is revealed that a threefold rotational symmetry element enforced by the epitaxial constraint along the [111] direction of BaTiO 3 introduces considerable instability among intrinsic tetragonal, orthorhombic, and rhombohedral phases. Such phase degeneracy induces ultrafine ferroelectric nanodomains (1-10 nm) with low-angle domain walls, which exhibit significantly enhanced dielectric and piezoelectric responses compared to the (001)-oriented BaTiO 3 film with uniaxial ferroelectricity. Therefore, the finding highlights the important role of epitaxial symmetry in domain engineering of oxide ferroelectrics and facilitates the development of dielectric capacitors and piezoelectric devices.

In order to strengthen the nanostructure and suppress the collapse of nanopores of resorcinol-formaldehyde (RF) aerogels during the drying process, graphene oxide (GO) was incorporated into the RF matrix to prepare GO-RF composite aerogels by sol-gel polymerization. The influences of GO content on the sol-gel process, structure, and physical properties of RF aerogels were investigated. The morphologies of composite aerogels were characterized by scanning electron microscopy and transmission electron microscopy, and it was found that GO was well dispersed in the RF matrix. In addition, GO can obviously accelerate the gelation of the RF solution and reduce both the drying shrinkage and aerogel density. As the content of GO increased from 0 to 2 wt%, both the linear shrinkage and density of composite aerogels decreased progressively from 28.3% to 2.0% and 506 to 195 kg m(-3), respectively, implying that GO is an effective additive for inhibiting the volume shrinkage of aerogels during the drying process.

SEM and TEM pictures show that GNSs can be well-dispersed in a carbon matrix. The resultant composite CAs exhibited high compression strength and extremely low thermal conductivity of 0.028 W m−1 K−1.

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Highly flexible silica aerogels were synthesized using methyltriethoxysilane (MTES) and polydimethylsiloxane (PDMS) as coprecursors via a two-step acid-base sol-gel method followed by ambient pressure drying. The effects of volume ratio of PDMS to MTES (S) on the flexibility were investigated in detail. It was found that, with the increase of S from 5% to 8.75%, both the Young's modulus and density of obtained aerogels decrease from 0.136 to 0.030 MPa and 0.098 to 0.064 gˑcm -3 , respectively. Aerogel produced at S of 8.75% shows excellent compressional and recoverable properties. Its maximal recoverable compressive strain is 70%. The unrecovered strains calculated immediately and 12 h after the compression to 60% strain for twenty times are 10.9 % and 3.1 %, respectively. The excellent flexibility performance of silica aerogel derived from MTES-PDMS makes it a promising silica aerogel material for special applications.