Radiation therapy (RT) is an effective and commonly used course of treatment for cancer. However, RT lacks specificity resulting in sever acute and chronic side effects. Radiosensitizers, like silver nanoparticles (Ag NPs), possess properties that allow for the localized enhancement of RT effects. Nanoscale smart drug delivery systems proved the ability to impose specificity on inherently non-specific treatments. In this work, microfluidics was used to fabricate a pH-sensitive gelatin methacryloy (GelMA) nanogel for the smart delivery of radiosensitizers into the tumor microenvironment. Optimization of synthesis parameters was described, and transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used for characterization. Successful synthesis using a flow focusing microfluidic device produced low-polydispersity (PDI ~0.06), 123 ± 2 nm pH-sensitive GelMA nanogels, loaded with ~ 11 nm Ag NPs. DLS was then used to obtain preliminary evidence of the release of Ag NPs from the nanogels through the appearance, over time, of a second particle population. Additionally, a second synthesis method involving the in situ synthesis of Ag NPs during the process of nanogel crosslinking was described. This work provides support for the use of microfluidic devices to produce low-polydispersity nanoscale smart drug delivery systems, with applications in enhancing the efficacy of RT.