Strings of single-walled carbon nanotubes (SWCNT) were prepared using an aqueous dispersion of gellan gum wrapped nanotubes and crosslinked using Ca2+ ions. Various formulations were evaluated to determine the parameters for successful string formation; these included 8–12 % nanotube by weight, 60–70 % gellan gum, and 20–30 % KCl. Strings showed electrical conductivity when dried between ITO electrodes. Conductivity variations were observed and potential sources of the variation identified. Proteins were attached to the carbon nanotube strings with peroxidase enzymatic activity detected following horseradish peroxidase attachment. This work provides a basis for development of electronic biosensors based on these carbon nanotube strings.