A Comprehensive Review of Micro/Nano Precision Glass Molding Molds and Their Fabrication Methods.

Micro/nano-precision glass molding (MNPGM) is an efficient approach for manufacturing micro/nanostructured glass components with intricate geometry and a high-quality optical finish. In MNPGM, the mold, which directly imprints the desired pattern on the glass substrate, is a key component. To date, a wide variety of mold inserts have been utilized in MNPGM. The aim of this article is to review the latest advances in molds for MNPGM and their fabrication methods. Surface finishing is specifically addressed because molded glass is usually intended for optical applications in which the surface roughness should be lower than the wavelength of incident light to avoid scattering loss. The use of molds for a wide range of molding temperatures is also discussed in detail. Finally, a series of tables summarizing the mold fabrication methods, mold patterns and their dimensions, anti-adhesion coatings, molding conditions, molding methods, surface roughness values, glass substrates and their glass transition temperatures, and associated applications are presented. This review is intended as a roadmap for those interested in the glass molding field.

Fabrication of a Plasmonic Nanoantenna Array Using Metal Deposition on Polymer Nanoimprinted Nanodots for an Enhanced Fluorescence Substrate.

A simple and cost-effective method is proposed herein for a plasmonic nanoantenna array (PNAA) for the fabrication of metal-enhanced fluorescence (MEF) substrates in which fluorophores interact with the enhanced electromagnetic field generated by a localized surface plasmon to provide a higher fluorescence signal. The PNAA is fabricated by the deposition of a silver (Ag) layer on an ultraviolet (UV) nanoimprinted nanodot array with a pitch of 400 nm, diameter of 200 nm, and height of 100 nm. During deposition, raised Ag nanodisks and a lower Ag layer are, respectively, formed on the top and bottom of the imprinted nanodot array, and the gap between these Ag layers acts as a plasmonic nanoantenna. Since the thickness of the gap within the PNAA is influenced by the thickness of Ag deposition, the effects of the latter upon the geometrical properties of the fabricated PNAA are examined, and the electromagnetic field intensity distributions of PNAAs with various Ag thicknesses are simulated. Finally, the fluorescence enhancement factor (FEF) of the fabricated PNAA MEF substrate is measured using spotted Cy5-conjugated streptavidin to indicate a maximum enhancement factor of ~22× for the PNAA with an Ag layer thickness of 75 nm. The experimental results are shown to match the simulated results.

Fabrication of Cross-Sinusoidal Anti-Reflection Nanostructure on a Glass Substrate Using Imperfect Glass Imprinting with a Nano-Pin Array Vitreous Carbon Stamp.

Although polymer nanoimprinting on glass substrates has been widely employed for the fabrication of functional anti-reflective (AR) nanostructures, several drawbacks exist with respect to durability and delamination. The direct patterning of glass material is a potential solution for outdoor applications that require AR functional nanostructured glass plates. In this study, a glass imprinting technique was employed for the fabrication of an AR nanostructure on a soda-lime glass substrate using a vitreous carbon (VC) stamp. The VC stamp, which had a high aspect ratio nanopost array with a pitch of 325 nm, diameter of 110 nm, and height of ~220 nm, was fabricated by the carbonization of a replicated Furan precursor from an Si master. During the glass imprinting process using the nanopost array VC stamp, the softened glass material gradually protruded into the spaces between the nanopins owing to viscoelastic behavior, and one can achieve a cross-sinusoidal surface relief under specific imprinting condition, which can be used as an AR nanostructure with a gradually increasing refractive index. The effects of the processing temperature on the surface profile of the glass imprinted parts and the measured transmission spectra were analyzed, and a glass imprinting temperature of 700 °C and pressure of 1 MPa were found to be the optimum condition. The height of the fabricated cross-sinusoidal nanostructure was 80 nm, and the light transmission was increased by ~2% over the entire visible-light range. Furthermore, the measured transmission spectrum observed to be in good agreement with the simulation results.

Antiproliferative activities and phenolic acid content of water and ethanolic extracts of the powdered formula of Houttuynia cordata Thunb. fermented broth and Phyllanthus emblica Linn. fruit.

BACKGROUND: Houttuynia cordata Thunb. and Phyllanthus emblica Linn. are native plants with medicinal and nutritive significance in Asia. The present study was aimed at evaluating antiproliferative effects on human cancer cell lines and identifying the phenolic acid composition of water and ethanolic extracts of the powdered formula of H. cordata fermented broth and P. emblica fruit. METHODS: Anticancer activity of the extracts was evaluated against HeLa, HT29, HCT116, MCF7 and Jurkat cells using an MTT assay and flow cytometric analysis of apoptosis induction and cell cycle arrest. Reverse phase HPLC was exploited for identification and quantification of some phenolic acids. RESULTS: MTT assay showed that both water and ethanolic extracts significantly decreased the viability of cancer cells in a dose- and time-dependent fashion. Based on the IC50 values, ethanolic extract (IC50 values = 0.12-0.65 mg/mL) was more cytotoxic than water extract (IC50 values = 0.22-0.85 mg/mL) and Jurkat cells were the most sensitive to both extracts (IC50 values = 0.12-0.69 mg/mL). The underlying mechanism for antiproliferative activity was apoptosis induction, especially in HT29, HCT116, MCF7 and Jurkat cells. HT29 cells were the most sensitive to extract-induced apoptosis. Ethanolic extract was more effective at inducing apoptosis than water extract. Moreover, cell cycle arrest was found to be another mechanism behind growth inhibition in Jurkat and HCT116 cells. However, these extracts were relatively less toxic to non-cancer Vero cells. HPLC analysis demonstrated that the powder mix extracts contained seven identified phenolic acids namely gallic, p-hydroxybenzoic, vanillic, syringic, p-coumaric, ferulic and sinapinic acids, where p-coumaric acid was detected in the highest concentration followed by ferulic acid. CONCLUSION: Overall, the results of this study suggest the powdered formula of H. cordata fermented broth and P. emblica fruit as an alternative medicine for cancer prevention and treatment.

Synergistic anticancer effects of cisplatin and histone deacetylase inhibitors (SAHA and TSA) on cholangiocarcinoma cell lines.

Clinical application of cisplatin against cholangiocarcinoma is often associated with resistance and toxicity posing urgent demand for combination therapy. In this study, we evaluated the combined anticancer effect of cisplatin and histone deacetylase inhibitors (HDACIs), suberoylanilide hydroxamic acid (SAHA) and trichostatin A (TSA), on the cholangiocarcinoma KKU-100 and KKU-M214 cell lines. Antiproliferative activity was evaluated using MTT assay. Apoptosis induction and cell cycle arrest were analyzed by flow cytometry. Cell cycle and apoptosis regulating proteins were evaluated by western blot analysis. MTT assay showed that cisplatin, SAHA and TSA dose-dependently reduced the viability of KKU-100 and KKU-M214 cells. The combination of cisplatin and HDACIs exerted significantly more cytotoxicity than the single drugs. Combination indices below 1.0 reflect synergism between cisplatin and HDACIs, leading to positive dose reductions of cisplatin and HDACIs. Cisplatin and HDACIs alone induced G0/G1 phase arrest in KKU-100 cells, but the drug combinations increased sub-G1 percent more than either drug. However, cisplatin and HDACIs alone or in combination increased only the sub-G1 percent in KKU-M214 cells. Annexin V-FITC staining revealed that cisplatin and HDACIs combinations induced more apoptotic cell death of both KKU-100 and KKU-M214 cells than the single drug. In KKU-100 cells, growth inhibition was accompanied by upregulation of p53 and p21 and downregulation of CDK4 and Bcl-2 due to exposure to cisplatin, SAHA and TSA alone or in combination. Moreover, combination of agents exerted higher impacts on protein expression. Single agents or combination did not affect p53 expression, however, combination of cisplatin and HDACIs increased the expression of p21 in KKU-M214 cells. Taken together, cisplatin and HDACIs combination may improve the therapeutic outcome in cholangiocarcinoma patients.