The National Institute of Standards and Technology (NIST), a non-regulatory federal agency within the U.S. Department of Commerce, pursues research to understand the physical interactions of ionizing and non-ionizing radiation with matter. Recent efforts include the radiation-induced synthesis and characterization of advanced nanomaterials, including soft nanomaterials for drug delivery applications, magnetic nanocomposites for imaging and electrical functions, adsorbents for environmental products, and membranes tailored for fuel cell uses. Aspects of the synthesis steps are being investigated, including the effects of temperature, dose, and the initial material concentrations and types on the control of the size, molecular weight, and functionality of the products. Material manipulations are also being examined, including polymer cross-linking and graft polymerization, and the kinetics of the formation and decay of transient species are being investigated using spectrophotometric pulse radiolysis. The development of measurement methods and standards for the precise and accurate characterization of the products is core to this effort to understand and optimize product production and performance. In this paper we describe measurements, standards, and data activities at NIST that support and advance research using ionizing radiation to optimize the synthesis of soft nanogels for drug or vaccine therapies. Nanogels are nano-sized crosslinked polymeric particles that form a three-dimensional, networked-matrix of soft, gelled particles in water. The gels are well suited to entrap and deliver medical-therapy molecules in vivo due to their unique size, structure, composition and shape. We are investigating the radiation synthesis of poly(vinylpyrrolidone) (PVP) nanogels via irradiation of dilute aqueous solutions of PVP with a pulsed electron beam. Characterization approaches include the use of dynamic light scattering to measure the size of the nanogels, as well as the use of time-dependent fluctuations of scattered light intensity, which arise from Brownian motion, to determine the hydrodynamic radius of the nanogels. Imaging of the nanogels using scanning and transmission electron microscopy in conjunction with an ionic liquid to improve the contrast of the nanogels when in solution is also being used to understand the distribution of polymer nanoparticles within the gel network.