ABSTRACT: Dramatic photochromic-change of 2,5-bis-
(triphenylamine)-substituted N,N′-diphenylpyrrolo-[3,2-b]pyrrole
(1) with halocarbons provides an effective route for halocarbon
analysis with the naked eye. The visual detection range can reach as
low as 10−4 ∼ 10−5 M (1−10 ppm) in CH3CN. This method can
also be applied for detection of CHCl3 in water. Fabrication of
a disposable paper test cartridge along with using a camera flash
as the light source allows on-site halocarbon detection in seconds.
Quantitative analysis for CHCl3 and CH2Cl2 have also been
demonstrated.