Figure 3.

(a) Plots of velocity versus applied potential for 5HT and 5HTrp photoproducts. Both plots scale linearly over the range of potentials examined here, demonstrating that Joule heating does not alter mobilities significantly even for fields >0.1 MV⋅cm⁻¹. Duplicate measurements were made at each applied potential value. (b) Band variance (σ², μm²) for 5HT and 5HTrp as a function of peak migration time with 2-μs nominal gating periods for each analysis. The solid curve represents ideal band variance calculated by using an rms focal dimension (σ_focus) of 0.265 μm, an rms gating duration (σ_gate) of 0.57 μs, and a product diffusion coefficient (D) of 6.5 × 10⁻⁶ cm²⋅s⁻¹. The same reagent solutions and capillary were used to acquire data in Figs. 2 and 3.