This review represents a comprehensive attempt to summarize and discuss various sensing applications of iron oxide nanoparticles (NPs), which have attracted a great deal of attention over recent years because of their easy preparation, biocompatibility, nontoxicity, and broad range of biomedical applications. We review the application potential of nanomagnetite based amperometic sensors possessing an intrinsic enzyme mimetic activity similar to that found in natural peroxidases. In addition, we discuss the properties and applications of enzymatic sensors exploiting glucose oxidase, tyrosinase, and other enzymes for sensing a variety of important biomedical species. Among iron oxide-based nanocomposites, we highlight the use of Fe 3 O 4 @Au hybrids for designing new electrochemical aptasensors with unique versatility for binding diverse targets, including proteins and peptides. Similarly, sensing applications of composites of iron oxide NPs with graphene derivatives and carbon nanotubes are reviewed. A large part of the review focuses on the development of DNA sensors and iron oxide based immunosensors for the detection of biological and chemical pathogens, contaminants, and other important analytes. Attention is also given to nonelectrochemical sensing, including various types of magnetic, fluorescence, and surface plasmon resonance sensors.

No abstract

We present the first example of covalent chemistry on fluorographene, enabling the attachment of -SH groups through nucleophilic substitution of fluorine in a polar solvent. The resulting thiographene-like, 2D derivative is hydrophilic with semiconducting properties and bandgap between 1 and 2 eV depending on F/SH ratio. Thiofluorographene is applied in DNA biosensing by electrochemical impedance spectroscopy.

Researchers should be cautious about the presence of metal impurities in commercial conductive filaments and its crucial effect on O2 based electrocatalysis, which is altered depending on the post 3D-printing treatment.