Protocol to extract tear fluid for proteomics using Schirmer strips

Schirmer strips are widely regarded as the gold standard for tear fluid collection. However, their use presents several challenges for proteomic analysis. Here, we present a protocol for extracting tear proteins from Schirmer strips. We describe steps for acquisition and handling of strips, extraction buffer preparation, strip preparation, and protein extraction. This protocol is designed to improve protein yield and facilitate proteomic workflows and is adaptable for various protein-based studies, particularly in the context of ocular disease research and diagnostics.