Binary wettability patterned surfaces with extremely high wetting contrasts can be found in nature on living creatures. They offer a versatile platform for microfluidic management. In this work, a facile approach to fabricating erasable and rewritable surface patterns with extreme wettability contrasts (superhydrophilic/superhydrophobic) on a TiO2 nanotube array (TNA) surface through self-assembly and photocatalytic lithography is reported. The multifunctional micropatterned superhydrophobic TNA surface can act as a 2D scaffold for site-selective cell immobilization and reversible protein absorption. Most importantly, such a high-contrast wettability template can be used to construct various well-defined 3D functional patterns, such as calcium phosphate, silver nanoparticles, drugs, and biomolecules in a highly selective manner. The 3D functional patterns would be a versatile platform in a wide range of applications, especially for biomedical devices (e.g., high-throughput molecular sensing, targeted antibacterials, and drug delivery). In a proof-of-concept study, the surface-enhanced Raman scattering and antibacterial performance of the fabricated 3D AgNP@TNA pattern, and the targeted drug delivery for site-specific and high-sensitivity cancer cell assays was investigated.

Frequency domain photon migration (FDPM) is a new method for characterization of concentrated colloidal suspensions using multiply scattered light. The ability of FDPM to determine size and interaction characteristics of the particulate phase of colloidal suspensions depends largely upon the accuracy and precision of FDPM-measured optical properties. In this work, FDPM measurements at multiple modulation frequencies and multiple source-to-detector distances are systematically analyzed for obtaining accurate and precise scattering properties of colloidal suspensions. Two different data analysis methods, multifrequency (MF) nonlinear regression and multidistance (MD) linear regression, and corresponding various strategies for fitting to the optical diffusion equation are investigated. The accuracy and precision of estimated scattering coefficients by different approaches are compared. Results show that MD linear regression with simultaneous regression of average intensity and phase shift or amplitude and phase shift data provides the best data analysis method since it provides not only accurate estimated parameters but also an accurate estimation of their uncertainties. Finally, an important criterion, derived from the photon diffusion model, is proposed for checking the consistency of measurement data and optimizing experimental conditions for FDPM characterization of multiply scattering materials.

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Costunolide, a sesquiterpene isolated from Vladimiria souliei (Franch.) Ling, is known to exhibit anti-inflammatory, anti-viral, and anti-tumor activities. However, the effects of costunolide on liver injury are poorly understood. The current study aimed to investigate the hepatoprotective effects of costunolide against lipopolysaccharide (LPS) and D-galactosamine-induced acute liver injury (ALI) in mice. The results indicated that costunolide (40 mg/kg) could significantly improve the pathological changes of hepatic tissue, and reduced the LPS and D-galactosamine-induced increases of alanine aminotransferase (from 887.24 ± 21.72 to 121.67 ± 6.56 IU/L) and aspartate aminotransferase (from 891.01 ± 45.24 to 199.94 ± 11.53 IU/L) activities in serum. Further research indicated that costunolide significantly reduced malondialdehyde content (from 24.56 ± 1.39 to 9.17 ± 0.25 nmol/ml) and reactive oxygen species (from 203.34 ± 7.68 to 144.23 ± 7.12%), increased the activity of anti-oxidant enzymes superoxide dismutase (from 153.74 ± 10.33 to 262.27 ± 8.39 U/ml), catalase (from 6.12 ± 0.30 to 12.44 ± 0.57 U/ml), and total anti-oxidant capacity (from 0.64 ± 0.06 to 6.29 ± 0.11 U/ml) in hepatic tissues. Western blot results revealed that costunolide may trigger the anti-oxidative defense system by inhibiting kelch-like ECH-associated protein 1 and nuclear factor-related factor 2 (cytosol), increasing nuclear factor-related factor 2 (nucleus), heme oxygenase-1 and NAD (P) H quinone oxidoreductase 1 activity. Moreover, costunolide significantly decreased the protein expression of proinflammatory cytokines including interleukin 1β, interleukin 6, and tumor necrosis factor. Pretreatment with costunolide could reduce the expression of toll-like receptor 4, myeloid differentiation factor 88, p65 (Nucleus), phosphorylated IκB kinase α/β, inhibitor of nuclear factor kappa-B kinase, inhibitor kappa Bα and prevent the expression of phosphorylated inhibitor kappa B kinase which repressed translocation of p65 from cytoplasm to nucleus. In addition, pretreatment with costunolide also inhibited hepatocyte apoptosis by reducing the expression of B-cell lymphoma 2 associated X, cytochrome C, cysteinyl aspartate specific proteinase 3, cysteinyl aspartate specific proteinase 8 and cysteinyl aspartate specific proteinase 9, and by increasing B-cell lymphoma 2. From the above analysis, the protective effects of costunolide against LPS and D-galactosamine-induced ALI in mice may be attributed to its anti-oxidative activity in nuclear factor-related factor 2 signaling pathways, anti-inflammatory suppression in nuclear factor-kappa B signaling pathways, and inhibition of hepatocyte apoptosis. Thus, costunolide may be a potential therapeutic agent in attenuating LPS and D-galactosamine -induced ALI in the future.

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Vertically aligned TiO 2 nanotube ͑VATN͒ array micropatterns were fabricated based on a versatile superhydrophilicsuperhydrophobic template. Scanning electron microscopy, optical microscopy, and an electron probe microanalyzer were systematically used to confirm the successful fabrication of the dual-scale ͑micro-/nanoscale͒ patterns and characterize their structure and morphology. The fabrication of the VATN patterning employed a simple photocatalytic lithography technique and mild reaction conditions at low temperature in the absence of a photoresist and a harmful chemical catalyst. This large-area dual-scale pattern based on the superhydrophilic-superhydrophobic template is expected to be a promising candidate for many applications in a broad range of scientific and technological areas, such as sensor arrays and optoelectronic devices.The wettability of a solid surface is an important property that is governed by both its chemical compositions and geometrical structures. 1-3 Superhydrophobicity with a water contact angle ͑CA͒ greater than 150°and superhydrophilicity with a CA below 5°are the two extreme cases and have attracted great interest due to their importance in fundamental research and practical application. 4-8 Fine surface roughness enhances the modest hydrophilicity and hydrophobicity to superhydrophilicity and superhydrophobicity, respectively. At present, compared to the fabrications and applications based on the modest hydrophilic-hydrophobic pattern, [9][10][11][12][13] there have been few reports on superhydrophilic-superhydrophobic patterning. 14,15 TiO 2 , a wide bandgap functional semiconductor with numerous applications in sensing, 16,17 optoelectronics, 18,19 and photocatalysts, 20,21 was chosen as the model system. Patterning TiO 2 nanostructures is particularly important in making new types of functional semiconductor devices and constructing micro-and nanoelectromechanical systems. Photolithography is the most powerful and successful technique for generating patterned structures over large areas. For the production of TiO 2 patterns, conventional photolithographic methods usually require polymer photoresists. However, it is difficult to find suitable etching conditions free of influence on the substrates at selective etching or to obtain high resolution pattern edges even after tearing the films during the liftoff process. To solve these problems, selective growth techniques have recently been developed. 22-24 For example, Masuda et al. reported the site-selective deposition of anatase TiO 2 in an aqueous solution using a seed layer. 22 Michel et al. reported a TiO 2 pattern built by the combination of selective wet etching and the reactive ion etching method. 23 However, these approaches have drawbacks in practical applications because of the need for expensive equipment, multiple complex steps, the use of resists, and the binding of a harmful metal catalyst, which greatly limit their utility in fabricating large areas of nanosize structures in a high throughput fashion. Therefore, t...

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