Magneto-plasmonic nanoparticles for non-toxic biomarker detection

We present our efforts to develop a novel non-toxic method for diagnostic biomarker extraction and concentration from biofluids, employing magneto-plasmonic nanoparticles. The method utilizes magnetic nanoparticles of a few nanometers bearing molecular traps for biomarkers on their surface, along with larger magnetic nanoparticles for catching smaller ones in a strong magnetic field gradient. The interference of an external permanent gradient magnetic field with the magnetic field of large nanoparticles enables the capture of small magnetic nanoparticles from their trajectories in a fluid. A magnetic system based on multiple blocks of magnets with alternative orientations produces a strong gradient magnetic field over the fluid surface, allowing for efficient nanoparticle concentration without direct contact with the liquid. Theoretical analysis and mathematical simulations confirm the feasibility of this method, indicating fast and robust biomarker extraction and concentration, thereby enhancing sensitivity in biomarker detection. Experimental validation supports the effectiveness of the magnetic system in concentrating magnetic nanoparticles, aligning with the mathematical predictions. This approach holds promise for developing advanced biosensors and diagnostic tools with improved sensitivity and selectivity. In addition, these results may be helpful in the development of microfluidic particle sorting technologies.