Open AccesspH measurements in 16-nL-volume solutions using terahertz chemical microscopy
Author(s) -
Toshihiko Kiwa,
Tatsuki Kamiya,
Tadatsugu Morimoto,
Kenji Sakai,
Keiji Tsukada
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.008232
Subject(s) - terahertz radiation , optics , femtosecond , materials science , microscopy , volume (thermodynamics) , laser , optoelectronics , physics , quantum mechanics
Terahertz chemical microscopy has been developed for measuring the pH of a solution using only a small volume. The microsolution wells were fabricated on the surface of the sensing plate using a conventional photolithograph technique. Because the pH value can be calculated from the amplitude of a terahertz wave directly radiated from a sensing plate by a femtosecond laser irradiation, this method does not require any reference electrode in the solution. Thus, pH measurement can be achieved with a volume as small as 16 nL.