Single walled carbon nanotubes (SWNT) are ideal in vivo fluorescent sensors due to their near infrared emission, specificity, and lack of photobleaching. Unfortunately, the small size of SWNT sensors allows for easy in vivo dispersion unless they are constrained, which frequently leads to interactions that destabilize SWNT sensing capabilities. Delivery of a liquid SWNT sensor allows for physical constraint without negative interactions between the sensor and the constraining material. Various methods of hydrogel encapsulation of large volumes of SWNT have been determined, providing a method to deliver macro-scale, biocompatible devices in vivo for extended SWNT sensor observation.