[A new spectral method for the determination of cationic surfactant based on the resonance scattering effect of AgI2- association particles].
In pH 3.5 NaAc-HCl medium, there is a maximum resonance scattering (RS) peak at 360 nm and a synchronous scattering peak at 470 nm for the association particle system of (CTMAB-AgI2)n in white color, with a diameter of 700 nm. The CTMAB concentration cCTMAB in the range of 2.0-50.0 x 10(-7) 4 mol x L(-1) is linear to the I360 nm value. Its regression equation is I360 nm = 2.03 x 10(7) cCTMB + 0.48, and regression coefficient is 0.9985. The detection limit is 8.0 x 10(-8) mol x L(-1). A new RS method has been proposed for the determination of cationic surfactant in samples with satisfactory results. The laser scattering and RS spectra show that CTMAB+ and AgI2- combine to CTMA-AgI2- association molecule by means of attractive forces. The association molecules automatically aggregate to (CTMA-AgI2)n association particles, so that the particles exhibit a resonance scattering peak at 360 nm, and the system is in white color.
Cheng
Yun-yan
YY
Department of Resource and Environmental Science, Guangxi Normal University, Guilin 541004, China.
Jiang
Zhi-liang
ZL
Liang
Ai-hui
AH