Abstract #0426

Narvainen J, Kauppinen R, Williamson D, Morris G

It is shown that radiation damping interacts with small probe tuning errors to cause significant asymmetry in Z-spectra of water and 0.4 M aqueous urea at 400 MHz. This may obscure the Z-spectrum asymmetry caused by chemical exchange and complicate the in vivo determination of pH via Z-spectroscopy when high Q coils and high fields are used.