Ion-Selective Electrode for Anionic Surfactants Using Hexadecyl Trimethyl Ammonium Bromide-Sodium Dodecylsulfate as an Active Ionophore

Table 4

Results of determining the concentration of SDS by potentiometric titration using anionic surfactant selective electrode compared with the two-phase titration in sample solutions.

Number	𝑉SDS (mL)	Potentiometric titration		Two-phase titration
		VHyamine (mL)	cSDS (mol L^−1)	VHyamine (mL)	cSDS (mol L^−1)
1	25.0	2.53	4.09 × 10^−4	2.51	4.06 × 10^−4
2	25.0	2.54	4.11 × 10^−4	2.52	4.08 × 10^−4
3	25.0	2.54	4.11 × 10^−4	2.53	4.09 × 10^−4
Average	25.0	2.54	4.11 × 10^−4	2.52	4.08 × 10^−4
RSD (%)^a			1.41		1.58

^aRelative standard deviation of potentiometric titration and two-phase titration method for triplicate measurements.