Comments on the “ordinary–extraordinary phase transition” of poly(lysine)

The “ordinary–extraordinary phase transition” of poly(lysine), first reported by Lin et al. [(1978) Biopolymers 17, 1041–1064], has been reexamined as a function of the data collection interval (Δt) and scattering angle (θ). These data suggest that the relaxation domains “split” as the ionic strength is lowered through the transition region. In contrast, fluorescence photobleaching recovery data of Ware and coworkers (personal communication) indicate the tracer diffusion coefficient is not sensitive to the “ordinary–extraordinary phase transition.” The apparent discrepancy between these two techniques is here proposed to be due to small ion effects on both the dynamics and the scattering power of the polyelectrolytes.