Figure 3. Spectra acquired from the phantom with the uniformly labeled ¹³C tracer with increasing t₁ in the 1D ge-HSQC (heteronuclear single quantum coherence).

The evolution time (t₁) was increased with 1 ms every step and started at 4.2 ms. Due to the ¹³C-¹³C couplings in the tracer, the signal now decays rapidly with increasing t₁.