title: SERS detection of Biomolecules at Physiological pH via aggregation of Gold Nanorods mediated by Optical Forces and Plasmonic Heating.
abstract: Strategies for in-liquid molecular detection via Surface Enhanced Raman Scattering (SERS) are currently based on chemically-driven aggregation or optical trapping of metal nanoparticles in presence of the target molecules. Such strategies allow the formation of SERS-active clusters that efficiently embed the molecule at the "hot spots" of the nanoparticles and enhance its Raman scattering by orders of magnitude. Here we report on a novel scheme that exploits the radiation pressure to locally push gold nanorods and induce their aggregation in buffered solutions of biomolecules, achieving biomolecular SERS detection at almost neutral pH. The sensor is applied to detect non-resonant amino acids and proteins, namely Phenylalanine (Phe), Bovine Serum Albumin (BSA) and Lysozyme (Lys), reaching detection limits in the μg/mL range. Being a chemical free and contactless technique, our methodology is easy to implement, fast to operate, needs small sample volumes and has potential for integration in microfluidic circuits for biomarkers detection.
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Fazio
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Cristiano
authors.initials: C
authors.lastname: D'Andrea
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Foti
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Messina
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Irrera
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Donato
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Villari
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Norberto
authors.initials: N
authors.lastname: Micali
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Onofrio M
authors.initials: OM
authors.lastname: Maragò
authors.affiliation: CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D'Alcontres 37, I-98156, Messina, Italy.
authors.forename: Pietro G
authors.initials: PG
authors.lastname: Gucciardi
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002417:Cattle; D002645:Chickens; D006046:Gold / Q000737:chemistry*; D006361:Heating; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D053768:Metal Nanoparticles; D009113:Muramidase / Q000032:analysis*; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010649:Phenylalanine / Q000032:analysis*; D012710:Serum Albumin, Bovine / Q000032:analysis*; D012996:Solutions; D013059:Spectrum Analysis, Raman / Q000295:instrumentation / Q000379:methods*
chemical_list: D012996:Solutions; D012710:Serum Albumin, Bovine; D010649:Phenylalanine; D006046:Gold; D009113:Muramidase