Figure 1: Setup for SERS measurements on bacterial volatiles.

(a) SEM images of the SERS substrate before and after leaning for formation of electromagnetic “hot spots” for SERS enhancement. (Courtesy of Kaiyu Wu. Reprinted with permission from editor of ref. 19). (b) The pump (1) induces a vacuum inside the vacuum chamber (2), leading to inflation of the bag (3) and exposure of the SERS substrate (4) to volatiles created by the bacterial culture (5) in the water bath (6).