An angular fluidic channel for prism-free surface-plasmon-assisted fluorescence capturing

Abstract

Surface plasmon excitation provides stronger enhancement of the fluorescence intensity and better sensitivity than other sensing approaches but requires optimal positioning of a prism to ensure optimum output of the incident light. Here we describe a simple, highly sensitive optical sensing system combining surface plasmon excitation and fluorescence to address this limitation. V-shaped fluidic channels are employed to mimic the functions of a prism, sensing plate, and flow channel in a single setup. Superior performance is demonstrated for different biomolecular recognition reactions on a self-assembled monolayer, and the sensitivity reaches 100 fM for biotin-streptavidin interactions. Using an antibody as a probe, we demonstrate the detection of intact influenza viruses at 0.2 HA units ml À 1 levels. The convenient sensing system developed here has the advantages of being prism-free and requiring less sample (1-2 ml), making this platform suitable for use in situations requiring low sample volumes.

Sensor chip design for increasing surface-plasmon-assisted fluorescence enhancement of the V-trench biosensor

“…Thus, it is deduced that high-refractive-index materials are desirable for V-trench chips. Accordingly, we chose high-refractive-index glass for press molding as the chip substrate material, which has a refractive index of 1.845 at a wavelength of 690 nm, and compared its ability with that of the chip made of polystyrene, 12) which has a refractive index of 1.584 at a wavelength of 690 nm. 18) The properties of V-trench chips made of pressmolding glass and polystyrene, derived by calculation, are shown in Table I.…”

Synthesis and characterization of cotton fiber-based nanocellulose

“…For the past few decades, researchers have paid an attention to nanoscience and nanotechnology, because of its dynamic properties and applications [1][2][3][4]. Nanotechnology ("nanotech") deals the manipulation on an atom and molecular scale.…”

Investigation on Optimally Performing Sensor Substrates through Bio-fouling of Immunoglobulin-Conjugated Gold Nanoparticles

“…In this regard, the sensitivity and stability of biosensors is highly dependent on the unique substrates used to analyse the biomolecular interactions. Thus, the generation of novel materials or nanostructures is essential for enhancing biosensor sensitivity [1].…”

“…The development of more sensitive biosensors could be useful in a variety of fields, including medical diagnosis, the identification of pathogens for the quality control of consumable items, and surveillance of emerging diseases. In fact, biosensors have already shown efficacy in the detection of life threatening diseases caused by early stage viral and bacterial infections [1][2][3]. However, the quality of a given sensor is determined by its level of sensitivity and specificity [4], which can be dependent on the degree of biological non-specificity of the sensing surfaces (bio-fouling).…”