Fig. 3

Highly efficient peptide labeling via nsPCR. A wide range of peptides (a–d, with increasing masses) with various K-residue numbers were tested using nsPCR labeling. Isotopic distributions of peptide 11 in e and insert in d confirmed the accuracy of the labeling results. w/o, without, w/, with. Individual peptide sequence information are listed in Table 1. Source data is provided in a Source Data file