Immobilized Poly(aryleneethynylene) pH Strips Discriminate Different Brands of Cola

Abstract

Fluorescent, water-soluble poly(p-aryleneethynylene)s (PAE) were immobilized on commercially available nylon membranes by using a slot plotter, creating fluorescent, barcode-like sensor strips. Digital imaging by using a standard digital camera, before and after immersion of the strips in buffers of different pH, displays a unique color for each pH value. Statistical evaluation, multivariate analysis of variance (MANOVA) and principal component analysis (PCA), of the acquired data revealed that the immobilized PAEs are superior to the identical fluorophores when dissolved. The pH sensor array discriminates 20 different brands of commercial-cola soft drinks through differences in pH and colorant-PAE interactions.

A poly(arylene ethynylene)-based microfluidic fluorescence sensor array for discrimination of polycyclic aromatic hydrocarbons

“…31 Amongst sensing materials, fluorescent conjugated polymers display signal amplification and multivalency effects. 32 Water-soluble PAEs discriminate bacteria, wines, whiskies, colas, 33 aromatic carboxylic acids, 34 saccharides, 35 and honey. 36 Recently, Tropp et al used an array of six fluorescent fluorene-based copolymers for the discrimination of PAHs.…”

A colorimetric sensor array based on natural pigments for the discrimination of saccharides

“…As an optical sensor array, the chemical colorimetric sensor array aims to mimic the human olfactory or visual system and to produce a unique fingerprint of each analyte that would then be used to detect and distinguish complex components. [14][15][16] This technology has been applied in many fields such as chemistry [16] and food science, [17] and has been applied successfully to the detection of samples of Cola, [18] liquor, [17] wine, [19] tea [20] and natural amino acids. [21] Additionally, in some recent studies, optical sensor arrays have been used as saccharide recognizers.…”

Investigating the Time Response of an Optical pH Sensor Based on a Polysiloxane–Polyethylene Glycol Composite Material Impregnated with a pH-Responsive Triangulenium Dye

“…Based on the discovery of the membrane properties of glass, an electrode sensitive to protons was developed. − A commercial pH meter was launched after 25 years of engineering . The colorimetric pH determination is based on indicator dyes, and the most successful commercialization is indicators immobilized on paper. , Development of fiber optics, photo diodes, and light-emitting diodes (LEDs) has provided the means for a second implementation of the colorimetric method . During the last 40 years, optical pH sensors have been developed, , yet only few are commercialized .…”