Abstract
The proof-of-principle demonstration of rapid whole blood bioassays based on microwave-accelerated metal-enhanced fluorescence (MAMEF) method using silver nanoparticle-deposited surfaces is presented. In this regard, spherical silver nanoparticles were deposited onto glass slides (silver nanoparticle films, SNFs) in a highly reproducible manner, which was assessed by optical absorption spectroscopy. Atomic force microscopy was employed to determine the size of the deposited silver nanoparticles. A model bioassay, based on the well-known interactions of biotinylated bovine serum albumin (b-BSA) and streptavidin was constructed on SNFs. The model bioassay was run at room temperature (metal-enhanced fluorescence (MEF)-based bioassay without microwave heating) for 60 minutes and with microwave heating (MAMEF-based bioassay) for 1 minute. In contrast to MEF-based bioassays that only allowed the use of samples in buffer solution, MAMEF-based bioassays afforded the use of whole blood samples. A lower detection limit of 1 nM and 0.01 nM for b-BSA was determined in MEF-based and MAMEF-based bioassays, respectively.
Highlights
Bioassays are commonly used for the detection of biomolecules and analytes present in biologically relevant samples [1]
The surface plasmon resonance peak at 430 nm for silver nanoparticles deposited onto 10 different glass slides showed a minimal ~2% variation, which provided a direct evidence for the effectiveness of this straightforward deposition method
MEFbased detection of a model protein, biotinylated bovine serum albumin (b-BSA), in buffer in the concentration range of 0.1-1000 nM was achieved within 60 minutes at room temperature
Summary
Bioassays are commonly used for the detection of biomolecules and analytes present in biologically relevant samples [1]. The quantitative detection of biomolecules and analytes are typically carried out by labeling the antibody/protein with an enzyme, [1] magnetic particles [2,3]or fluorophores [4,5] followed by the conversion the measured signal to the concentration of the unknown biomolecules or analytes. Fluorescence-based readout for signal transduction is one of the most widely used technique in bioassays. The sensitivity of the fluorescence-based bioassays is mainly affected by the quantum yield of the fluorophore used to label the detector antibody/protein and the type of optical detectors used in collecting the fluorescence readout [6]. The total assay time is controlled by the binding kinetics of the proteins, which takes up to 20 minutes with automated miniature instruments including sample preparation or several hours in a typical laboratory setting [7].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
