Plasmonic Metal Nanoparticles Hybridized with 2D Nanomaterials for SERS Detection: A Review.

In SERS analysis, the specificity of molecular fingerprints is combined with potential single-molecule sensitivity so that is an attractive tool to detect molecules in trace amounts. Although several substrates have been widely used from early on, there are still some problems such as the difficulties to bind some molecules to the substrate. With the development of nanotechnology, an increasing interest has been focused on plasmonic metal nanoparticles hybridized with (2D) nanomaterials due to their unique properties. More frequently, the excellent properties of the hybrids compounds have been used to improve the drawbacks of the SERS platforms in order to create a system with outstanding properties. In this review, the physics and working principles of SERS will be provided along with the properties of differently shaped metal nanoparticles. After that, an overview on how the hybrid compounds can be engineered to obtain the SERS platform with unique properties will be given.

Synthesis and characterization of thermosensitive PNIPAM microgels covered with superparamagnetic gamma-Fe2O3 nanoparticles.

In the present study we report a facile and reproducible method of preparing magnetic thermosensitive hybrid material based on P(NIPAM) microgels covered with gamma-Fe2O3 nanoparticles of 6-nm size. The iron oxide nanoparticles provided magnetic response to the microgels. In addition, the presence of the magnetic nanoparticles on the microgels altered their swelling behavior and shifted their volume phase transition temperature to higher values. In particular, for inorganic shells with 18% (w/w) of magnetic nanoparticles the volume phase transition of the microgels was shifted from 36 to 40 degrees C. In contrast, for shells consisting of 38% (w/w) magnetic nanoparticles the volume phase transition of the microgels was almost blocked, thus indicating that the microgel thermal response was strongly affected by the presence of the inorganic nanoparticles. The synthesized thermosensitive magnetic microgels are envisaged to be ideal for potential applications as thermosensitive targeted drug delivery systems.