Table 8.
The results of potentiometric titrations of cationic surfactants in commercial disinfectants and antiseptics samples using SDS (c = 4 mM) as a titrant and DMI-TPB sensor containing plasticizer P5 as an indicator, in comparison with published DMI-TPB sensor containing P1.
| Product | CATIONIC SURFACTANT CONTENT * | ||||
|---|---|---|---|---|---|
| DMI-TPB Sensor with P1 | Surfactant Sensor ** | Two-Phase Titration | |||
| % | RSD (%) | % | RSD (%) | % | |
| A | 4.38 | 0.36 | 4.32 | 0.41 | 4.33 |
| B | 5.26 | 0.38 | 5.13 | 0.62 | 5.15 |
| C | 4.70 | 0.31 | 4.76 | 0.42 | 4.71 |
| D | 4.80 | 0.35 | 4.72 | 0.48 | 4.77 |
| E | 0.06 | 0.26 | 0.07 | 0.35 | 0.07 |
| F | 0.15 | 0.45 | 0.15 | 0.25 | 0.16 |
* average of 5 determinations; ** sensor developed in [20].