Analytical chemistry

1520-68828772015Apr07Analytical chemistryAnal ChemCharacterization of nitrazine yellow as a photoacoustically active pH reporter molecule.362336303623-3010.1021/ac503515kThroughout the fields of biomedical imaging, materials analysis, and routine chemical analysis, it is desirable to have a toolkit of molecules that can allow noninvasive/remote chemical sensing with minimal sample preparation. Here, we describe the photophysical properties involved in photoacoustic (PA) measurements and present a detailed analysis of the requirements and complications involved in PA sensing. We report the use of nitrazine yellow (NY) as a well-behaved PA pH reporter molecule. Both the basic and acidic forms of NY are photoacoustically well-behaved and allow for rapid and noninvasive measurement of pH in either transparent or turbid media. We also find that the serum protein-bound form of NY is photoacoustically well-behaved and should permit applications in noninvasive 3D imaging (e.g., the lymphatic system).BrownJordan EJEDepartment of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, Florida 33965-6565, United States.DiazLilibetLDepartment of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, Florida 33965-6565, United States.Christoff-TempestaTyTDepartment of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, Florida 33965-6565, United States.NesbittKathryn MKMDepartment of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, Florida 33965-6565, United States.Reed-BettsJuliaJDepartment of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, Florida 33965-6565, United States.SanchezJohnJDepartment of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, Florida 33965-6565, United States.DaviesKevin WKWDepartment of Chemistry and Physics, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers, Florida 33965-6565, United States.engJournal Article20150317