Magneto-plasmonic nanostructures functionalized with cell targeting units are of great interest for nanobiotechnology applications. Photothermal treatment of cells targeted with antibody functionalized nanostructures and followed by magnetic isolation, allows killing selected cells and hence is one of the applications of great interest. The magneto-plasmonic nanostructures reported herein were synthesized using naked gold and magnetite nanoparticles obtained through a green approach based on laser ablation of bulk materials in water. These particles do not need purifications steps for biocompatibility and are functionalized with a SERRS (surface enhanced resonance Raman scattering) active molecule for detection and with an antibody for targeting prostate tumor cells. Quantitative results for the cell targeting and selection efficiency show an overall accuracy of 94% at picomolar concentrations. The photothermal treatment efficiently kills targeted and magneto-selected cells producing a viability below 5% after 3 min of irradiation, compared with almost 100% viability of incubated and irradiated, but non targeted cells.

Nanoclusters with plasmonic and magnetic properties are obtained with naked gold (AuNP) and iron oxide nanoparticles (FeO x NP) separately synthesized by laser ablation in water and simply assembled by using their opposite surface charges. Controlling the amount of AuNP and FeO x NP, we obtained nanoclusters with both good surface-enhanced resonance Raman scattering (SERRS) signals and superparamagnetic properties. Nanoclusters are incubated with murine macrophage cells which, after mixing with other macrophages, can be magnetically guided in solution by sorting them in less than 10 min. SERRS signals, observed at the single cell level, were recorded for the sorted macrophages, showing that the nanoclusters are active also in a biological environment and allow the identification of the incubated macrophage cells.