Synthesis of superparamagnetic bare Fe3O4 nanostructures and core/shell (Fe3O4/alginate) nanocomposites

► Synthesis of bare Fe3O4 and core/shell (Fe3O4/alg NCs) at low temperature. ► Core/shell (Fe3O4/alg NCs) were synthesized by in-situ polymerization process. ► Superparamagnetic nature of Fe3O4 and core/shell (Fe3O4/alg NCs). ► Magnetic properties of the synthesized products were tuned by varying the pH.