Surface Plasmon Resonance Biosensors with Magnetic Sandwich Hybrids for Signal Amplification

Abstract

The conventional signal amplification strategies for surface plasmon resonance (SPR) biosensors involve the immobilization of receptors, the capture of target analytes and their recognition by signal reporters. Such strategies work at the expense of simplicity, rapidity and real-time measurement of SPR biosensors. Herein, we proposed a one-step, real-time method for the design of SPR biosensors by integrating magnetic preconcentration and separation. The target analytes were captured by the receptor-modified magnetic nanoparticles (MNPs), and then the biotinylated recognition elements were attached to the analyte-bound MNPs to form a sandwich structure. The sandwich hybrids were directly delivered to the neutravidin-modified SPR fluidic channel. The MNPs hybrids were captured by the chip through the neutravidin–biotin interaction, resulting in an enhanced SPR signal. Two SPR biosensors have been constructed for the detection of target DNA and beta-amyloid peptides with high sensitivity and selectivity. This work, integrating the advantages of one-step, real-time detection, multiple signal amplification and magnetic preconcentration, should be valuable for the detection of small molecules and ultra-low concentrations of analytes.

Enhancing urine glucose sensing performance through the introduction of two dimensional-transition metal dichalcogenides and gold nanoparticles into silver/UiO-66 chip of surface plasmon resonance

“…A surface plasmon resonance (SPR)-based sensor is an optical sensor that can quickly detect the presence of various biomolecules with simple preparation [4,5]. However, the detection of glucose using the SPR sensor is not optimal because of the low molecular weight of glucose [6]. The SPR sensor can optimally detect biomolecules with a molecular weight of more than 200 Da, while the molecular weight of glucose is 180 Da [7,8].…”

Label-Free Direct Detection of Cylindrospermopsin via Graphene-Enhanced Surface Plasmon Resonance Aptasensor

“…Recently, SPR has been used for the detection of cyanotoxins generated by algal blooms [ 9 ]. The technique demonstrated less sensitivity to such small molecules than a standard ELISA detection [ 10 ], hence additional SPR signal amplification methods must be developed [ 11 ]. In fact, there is a need for a highly sensitive direct assay for in-field rapid diagnostics of water quality.…”

Ionic liquid‐based materials for electrochemical biosensing

“…Among aqueous electrolytes, phosphate‐buffered saline is the most prevalent 4 . Other examples of aqueous electrolytes include deionized water, 5–8 salt solutions such as KCl/HEPES, 9 NaOH, 10–13 and various cell culture media including mTeSR, 14 Dulbecco's modified Eagle's medium, 15 or Bold's basal medium 16 …”

“…4 Among aqueous electrolytes, phosphate-buffered saline is the most prevalent. 4 Other examples of aqueous electrolytes include deionized water, [5][6][7][8] salt solutions such as KCl/HEPES, 9 NaOH, [10][11][12][13] and various cell culture media including mTeSR, 14 Dulbecco's modified Eagle's medium, 15 or Bold's basal medium. 16 In the first decade of the 20th century, a group of researchers introduced a new type of electrolyte using a combination of concentrated nitric acid and ethylamine synthetized ethyl ammonium nitrate ionic liquids (ILs) (EtNH 3 )(NO 3 ).…”