Fluorescent dye N,N'-dioctadecylrhodamine as a new interfacial acid-base indicator.
This paper reports the spectral properties and protolytic behavior of the fluorescent dye N,N'-dioctadecylrhodamine on the micelle/water and microdroplet/water interfaces as well as in Langmuir-Blodgett films soaked into aqueous media. Long hydrocarbon chains provide similar orientation of its cation and zwitterion, with the dissociating group (COOH-->COO(-)) directed toward the bulk (aqueous) phase. Both absorption and fluorescence of the dye can be used for monitoring electrical surface potentials and for determination of bulk pH.
V.N. Karazin Kharkov National University, 61077 Kharkov, Ukraine. mchedlov@univer.kharkov.ua
N O
NO
McHedlov-Petrossyan
N A
NA
Vodolazkaya
O N
ON
Bezkrovnaya
A G
AG
Yakubovskaya
A V
AV
Tolmachev
A V
AV
Grigorovich
D005456:Fluorescent Dyes / Q000737:chemistry*; D007202:Indicators and Reagents; D008823:Micelles; D012235:Rhodamines / Q000737:chemistry*; D012996:Solutions; D013050:Spectrometry, Fluorescence; D013229:Stearic Acids / Q000737:chemistry
D005456:Fluorescent Dyes; D007202:Indicators and Reagents; D008823:Micelles; C529664:N,N'-dioctadecylrhodamine; D012235:Rhodamines; D012996:Solutions; D013229:Stearic Acids; C031183:stearic acid