"Fluorescence pH probe based on microstructured polymer optical fibre", Optics express, 2007, 15: 16478-16483
A kind of optical pH sensor was demonstrated that is based on a
pH-sensitive fluorescence dye-doped (eosin) cellulose acetate (CA) thinfilm
modified microstructured polymer optical fiber (MPOF). It was
obtained by directly inhaling an eosin-CA-acetic acid mixed solution into
array holes in a MPOF and then removing the solvent (acetic acid). The
sensing film showed different fluorescence intensities to different pH
solutions in a pH range of 2.5–4.5. Furthermore, the pH response range
could be tailored through doping a surfactant, hexadecyl trimethyl
ammonium bromide (CTAB), in the sensing film.