How nanoparticles encapsulating fluorophores allow a double detection of biomolecules by localized surface plasmon resonance and luminescence

Abstract

The paper shows how polysiloxane particles encapsulating fluorophores can be successfully used to detect biotin-streptavidin binding by two types of technique. After functionalization of the particles by streptavidin, the fixation of the biomolecule can indeed be detected by a shift of the localized surface plasmon resonance of the biotinylated gold dots used as substrate and by the luminescence of the fluorophores evidenced by scanning near-field optical microscopy. The development of particles allowing such a double detection opens a route for increasing the reliability of biological detection and for multi-labelling strategies crossing both detection principles.

RETRACTED: Plasmonic Nanostructures Prepared by Soft UV Nanoimprint Lithography and Their Application in Biological Sensing

“…The index difference between air and streptavidin molecule is ∆n = 0.56 [2]. The size of streptavidin molecule is around 6 nm [2,3]. Firstly, the LSPR peak of the Au nanodisk arrays was determined and λ LSPR = 605 nm ( Figure 4).…”

“…In recent decades, in order to sense biological molecules by localized surface plasmon resonance (LSPR) on metallic nanoparticles, the capability to prepare high-density nanostructures over large areas is gaining growing importance [1][2][3]. Extinction spectroscopy measurements are mainly used to characterize these plasmonic nanostructures on an area of 100 × 100 μm 2 [4,5].…”

Nanohybrids Near-Field Optical Microscopy: From Image Shift to Biosensor Application

“…As the excitation wavelength (633 nm) is outside this range, we assign the emission of light from Rhodamine to an indirect excitation process. The gold nanoplots absorb light at 633 nm [51] and emit a broad LSPR relaxation spectrum extending from 550 nm to 750 nm. This includes the margin within the 540-600 nm band for the excitation of Rhodamine as illustrated in Figure 10(c).…”

Latest Novelties on Plasmonic and Non-Plasmonic Nanomaterials for SERS Sensing

“…The strong development of plasmonic nanomaterials for various applications such as photovoltaics [ 1 , 2 , 3 , 4 ], optical devices [ 5 , 6 , 7 , 8 , 9 , 10 ], and biochemical sensors [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ] has taken place over these last ten years. The plasmonic nanostructures can also enable the detection of phase transitions under high-pressure conditions [ 18 ], the luminescence upconversion enhancement [ 19 , 20 ], and the optical tuning of photoluminescence [ 21 ] and upconversion luminescence [ 22 ].…”