Figure 2.

In-strip protein digestion (Method B) provides a significant increase in both protein and peptide yield compared to post-extraction protein digestion (Method A) in tear fluid samples. The average protein and peptide counts per sample identified in all four workflows were compared via two-way ANOVA with Tukey’s correction. (A) Method B identified more proteins than Method A when paired with both CID and HCD fragmentation. (B) In-strip protein digestion also identified more peptides than post-extraction digestion following both CID and HCD fragmentation. Results are expressed as means ± SD; n = 11/group; * p-value <0.05.