Dextran nanoparticles are grabbing world-wide attention of scientists and technologists for their wide-ranging applications as biomaterials. Dextran, a type of α-glucan is the first commercialized bacterial exopolysaccharide that exhibits high biocompatibility and biodegradability features enabling a large array of applications. This chapter concisely compiles the chemical and enzymatic methods of synthesis, characteristics and myriad applications of dextran-based nanoparticles such as nanocarriers, bioimaging, drug delivery, nanobiosensors, and nanoscaffolds to mention a few. A comprehensive understanding of other dextran-based conjugates, derivatives, hydrogels and micelles being used as nanomedicine is also presented. Although literature reveals sporadic distribution of cytotoxicity studies of dextran-based nanoparticles, a detailed review is accounted for future scope of study. The chapter concludes with an emphasis on the paradigm shift in exploiting dextran for trending applications in nanobiotechnology.