Table 9.
Experimental data for the standard additions plot reported in Figure 12. V1b and VDQ are the added volumes of the standard methanol solutions of [1b] = 2500 μg L−1 and [DQ] = 1500 μg L−1, respectively. A tap water sample was spiked and divided into 8 aliquots. The spike concentration of 1.0 μg L−1 was normalized to the total volume of 2500 μL, 60/40 methanol/water.
| Entry | Vsample, μL | V1b, μL | VDQ, μL | VTOT, μL | [1b], μg L−1 | [DQ], μg L−1 | ΔF * |
|---|---|---|---|---|---|---|---|
| 1 | 1000 | 25 | 0 | 2500 | 25.0 | 0.0 | 0.3 |
| 2 | 1000 | 25 | 5 | 2500 | 25.0 | 3.0 | 2.1 |
| 3 | 1000 | 25 | 15 | 2500 | 25.0 | 9.0 | 4.5 |
| 4 | 1000 | 25 | 25 | 2500 | 25.0 | 15.0 | 6.8 |
| 5 | 1000 | 25 | 50 | 2500 | 25.0 | 30.0 | 13.6 |
| 6 | 1000 | 25 | 75 | 2500 | 25.0 | 45.0 | 19.6 |
| 7 | 1000 | 25 | 100 | 2500 | 25.0 | 60.0 | 27.2 |
| 8 | 1000 | 25 | 125 | 2500 | 25.0 | 75.0 | 33.5 |
* The fluorescence change ΔF = F0 − F was calculated with respect to the F0 value measured in a non-spiked water sample obtained as in entry 1, but from ultrapure, HPLC-grade water. The fluorescence values were measured at 416 nm for anthracene fluorophore 1b. ΔF was calculated as the average value of three independent determinations.