Recently, magnetic nanomaterials have been extensively studied and their potential applications have been investigated in various fields. Due to their superparamagnetic properties, Fe3O4 NPs are valuable candidates as diagnostic agents in many different applications such as biosensing, cell labeling, therapeutic probing, including drug delivery, bacteria detection, and magnetic separation. According to the study carried out in this investigation, Fe3O4 magnetite nanoparticles (MNPs) and their surface coating with saccharides (i.e., starch and dialdehyde starch (DAS)) are reported using different strategies. The purpose of using starch as a coating agent is not only to protect MNPs from oxidation and aggregation; but also, starch is a biodegradable material that can be degraded by certain bacterial enzymes such as α-Amylases. This makes starch a valued diagnostic agent for bacterial detection. Two different chemical techniques were applied to synthesize MNPs; co-precipitation and solvothermal for different physical properties, shapes, and size distributions. Starch and its oxidized form (dialdehyde starch; DAS) were grafted on the MNPs surface using different starch/DAS percentages. Different percentages aimed to optimize the coating shell thickness to maintain the magnetic properties of MNPs core. The prepared starch/ Fe3O4 MNPs samples are characterized by structural and morphological chemical analyses such as TGA, FT-IR, DLS at the Biofilm Research Center for Biointerfaces at Malmö University. SEM and TEM imaging for morphological characterization was done by our collaborators from Nanostructured Materials Group, GMN, Instituto Universitario de Ciencia de Los Materiales (ICMUV), Valencia University, Spain.