Figure 2.

Electrophoretic characterization of transient photochemical products created from mixtures of the 5-hydroxyindoles 5HT and 5HTrp (both 250 μM) by using a separation distance of 10 μm. The bottom two traces are analyses of a reaction mixture produced by using a field of 0.12 MV⋅cm⁻¹ (20 kV). Baseline resolution of the two fluorescent products is achieved in ≈19.5 μs. Photon-counting bin sizes were 640 ns (open circles) and 320 ns (black circles). The top trace (gray circles) demonstrates analysis with 0.06 MV⋅cm⁻¹ (10 kV) and 640-ns data bins and has been compressed 2-fold in the horizontal dimension to facilitate comparison to the faster, higher-field separations. The nominal gating period for each analysis was 2 μs; ≈50,500 and 65,500 repeat electrophoretic events were summed to generate the 10- and 20-kV traces, respectively. The y axis values represent actual counts for the 20-kV (640-ns) trace, with the other analyses displaced vertically for ease of visual comparison.