Fig. 5.
Efficient mixing on microcoils for sophisticated photo-CIDNP applications. a An experiment to promote solvent burial of a polarizable molecule. Mixing of 10 mM AcTyr and 2 mM FMN (through a syringe, ‘1’) with 30 mM β-cyclodextrin (β-CyD) (using another syringe, ‘2’), results in a mixture of 5 mM AcTyr, 1 mM FMN and 15 mM β-CyD in the detection region in which the amino acid becomes encapsulated. Its lower solvent exposure (and therefore accessibility to FMN), causes the AcTyr signal to broaden and shift (see also Supplementary Figure 3). b An experiment to promote solvent exposure of a polarizable molecule. Mixing of 4 mM LytA239–252 and 2 mM FMN (syringe 1) with 9 M urea (syringe 2), results in a mixture of 2 mM LytA239–252, 1 mM FMN and 4.5 M urea in the detection region in which LytA239–252 loses the native structure and the two tyrosines become solvent exposed. The higher accessibility to FMN yields two signals corresponding to the Hε protons of two distinct tyrosines show up in the spectra. Note the highly reproducible pattern in both cases when the mixing is turned on and off