Significant unmet diagnostic need exists for diseases characterized by changes in T2 relaxation properties of tissue, especially those related to changes in fluid volume status and muscle disorders. Current methods for quantifying these disorders, such as MRI, are resource-intensive limiting widespread adoption. We introduce a novel method of quantitative tissue separation using single-sided magnetic resonance sensors. We explore pulse sequences and fitting techniques to characterize distinct tissue compartments in heterogeneous samples. We then extend these techniques to in vitro and in vivo models, and we finally apply them to measure the progression of acute muscle edema in an animal model.