Spectrophotometric determination of trace cetyltri methyl ammonium bromide by nanosilver

摘要

The decolored reaction between cetyltrimethyl ammonium bromide (CTMAB) and nanosilver was studied, and a simple, rapid spectrophotometric method was established to determine CTMAB. In pH 7.8 Na_2HPO_4NaH_2PO_4 buffer solution, nanosilver exhibited a maximum absorption peak at 395 nm, and it reacted with CTMAB to form larger particles that resulted in the absorption decreasing. Under the chosen conditions, the decreased absorbance was linear to the CTMAB concentration in the range of 2.5 × 10~(-7)-1.0 × 10~(-5)mol/L, with the regression equation of AA395 = 0.0431C ctmab + 0.0182, the correlation coefficient of 0.9968 and the detection limit of 0.21ìmol/L CTMAB. The proposed method was applied to detect CTMAB in water samples, with simplicity, rapidity and accuracy.