Optical Aggregation of Gold Nanoparticles for SERS Detection of Proteins and Toxins in Liquid Environment: Towards Ultrasensitive and Selective Detection

Materials

Barbara Fazio¹  Onofrio M. Maragò¹  Antonino Foti¹  Norberto Micali¹  Maria Grazia Donato¹  Cristiano D’Andrea¹  Valentina Villari¹  Pietro G. Gucciardi¹  Raymond Gillibert²  Marc Lamy de la Chapelle² 

[1] CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F. Stagno D’Alcontres 37, I-98168 Messina, Italy;Laboratoire CSPBAT, Université de Paris 13, Sorbonne Paris Cité, CNRS, 74 Rue Marcel-Cachin, F-93017 Bobigny, France;

关键词: SERS;    biosensor;    gold nanoparticles;    aptamers;    toxins;    hemeprotein;    optical forces;    optical tweezers;    optical patterning;    colloids;   

DOI  :  10.3390/ma11030440

来源: DOAJ

【 摘 要 】

Optical forces are used to aggregate plasmonic nanoparticles and create SERS–active hot spots in liquid. When biomolecules are added to the nanoparticles, high sensitivity SERS detection can be accomplished. Here, we pursue studies on Bovine Serum Albumin (BSA) detection, investigating the BSA–nanorod aggregations in a range from 100 µM to 50 nM by combining light scattering, plasmon resonance and SERS, and correlating the SERS signal with the concentration. Experimental data are fitted with a simple model describing the optical aggregation process. We show that BSA–nanorod complexes can be optically printed on non-functionalized glass surfaces, designing custom patterns stable with time. Furthermore, we demonstrate that this methodology can be used to detect catalase and hemoglobin, two Raman resonant biomolecules, at concentrations of 10 nM and 1 pM, respectively, i.e., well beyond the limit of detection of BSA. Finally, we show that nanorods functionalized with specific aptamers can be used to capture and detect Ochratoxin A, a fungal toxin found in food commodities and wine. This experiment represents the first step towards the addition of molecular specificity to this novel biosensor strategy.

【 授权许可】

Unknown