 The study examined how changing the pH of a protein affected its ability to aggregate when it came into contact with a liquid gas interface. It found that lowering the pH caused more protein to aggregate at the interface, but only if the protein had been previously unfolded. This suggests that the unfolded protein is more likely to aggregate at the interface than the native protein. This article was authored by Ru-A-Li, Zhao Liang-Wu, Yan Ji-Wang, and others.