Patterned Deposition of Sol-Gel Thin Films Using an Airbrush

ABSTRACT

In this article, we present a method to pattern glass substrates with sol-gel derived thin films. This method is based on the aerosol deposition of sol-gel precursor solutions using an inexpensive, commercially available airbrush. The technique was demonstrated using Cy5-doped sol-gel thin films for the creation of wavelength conversion devices. The films deposited were mechanically and chemically rigid, and patterns could be achieved with a resolution limit of approximately 250 μm. Constructing channel waveguides was also attempted using both zirconium- and titanium-based sol-gel thin films. Deposited thin films of these materials showed graininess that limited the ability to couple light into the films and increased the observed scatter. However, light was successfully coupled into the titanium-based sol-gel film using small lens-like structures created on the glass surface.     

A one‐step matrix application method for MALDI mass spectrometry imaging of bacterial colony biofilms

Matrix‐assisted laser desorption/ionization imaging of biofilms cultured on agar plates is challenging because of problems related to matrix deposition onto agar. We describe a one‐step, spray‐based application of a 2,5‐dihydroxybenzoic acid solution for direct matrix‐assisted laser desorption/ionization imaging of hydrated Bacillus subtilis biofilms on agar. Using both an optimized airbrush and a home‐built automatic sprayer, region‐specific distributions of signaling metabolites and cannibalistic factors were visualized from B. subtilis cells cultivated on biofilm‐promoting medium. The approach provides a homogeneous, relatively dry coating on hydrated samples, improving spot to spot signal repeatability compared with sieved matrix application, and is easily adapted for imaging a range of agar‐based biofilms. Copyright © 2016 John Wiley & Sons, Ltd.     

Preparation of a solution‐processable,nanostructured ionic polyacetylene

Polymerization of a self‐assembled 1‐dodecyl‐3‐propargylimidazolium bromide ionic liquid (IL) yields a nanostructured ionic polyacetylene. A 1:1 aqueous mixture of the amphiphilic IL produces an ordered lyotropic mesophase that adopts a hexagonal perforated lamellar structure. Rh (I)‐mediated polymerization of the assembled mixture yields a hexagonal modulated lamellar structured polymer. FTIR spectroscopy reveals that the polymer was self n‐doped. The polymer was fractioned into three components with the majority product, possessing an intermediate molecular weight that is soluble in polar organic solvents. In methanol, the optical band gap of the main fraction was determined to be 2.38 eV and was nonemissive. The solution‐processable polymer was airbrush sprayed onto glass substrates to give a liquid‐crystalline, lamellar structured semiconductive film (7.02 × 10^?5 S cm^?1). The polymer resisted oxidation (degradation) upon storage in air as monitored by vibrational spectroscopy. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 , 51, 1215–1227