Tuning the surface chemistry of iPDMS for improved protein microarray performance

Protein microarrays meet the need for large-scale, low cost and accurate assays in the post-genomic era. Efforts in revealing the internal relationship between surface chemistry and microarray quality may greatly help the realization of widespread protein microarray use. In this paper, we prepared iPDMS with various surface properties, which were studied in combination with other parameters such as [protein], spot size and environment conditions to identify the causes of array defects (exosmosis, coffee ring and overflow) and corresponding strategies to avoid them. Through this research, we determined that the optimal parameters and conditions of protein microarray fabrication for an iPDMS sheet were 50° < contact angle < 90°: array volume ≤10 nL, [capture antibody] at 50 μg mL^-1, fixed at 25 °C, and 60% humidity. We also identified some characteristics of protein microarray fabrication that may benefit other solid supporting materials (SSM) and serve as a good model of proteins interacting with various bio-interfaces.