Selective counting and sizing of single virus particles using fluorescent aptamer-based nanoparticle tracking analysis

Abstract

Detection and counting of single virus particles in liquid samples are largely limited to narrow size distribution of viruses and purified formulations. To address these limitations, here we propose a calibration-free method that enables concurrently the selective recognition, counting and sizing of virus particles as demonstrated through the detection of human respiratory syncytial virus (RSV), an enveloped virus with a broad size distribution, in throat swab samples. RSV viruses were selectively labeled through their attachment glycoproteins (G) with fluorescent aptamers, which further enabled their identification, sizing and counting at the single particle level by fluorescent nanoparticle tracking analysis. The proposed approach seems to be generally applicable to virus detection and quantification. Moreover, it could be successfully applied to detect single RSV particles in swab samples of diagnostic relevance. Since the selective recognition is associated with the sizing of each detected particle, this method enables to discriminate viral elements linked to the virus as well as various virus forms and associations.

Potential Diagnostic Systems for Coronavirus Detection: a Critical Review

“…Lastly, aptamers have been used to modify lateral flow assay (LFA) for virus detection [ 107 ]. Fluorescent aptasensors, which can be categorized into aptasesnors that respond with fluorescent intensity [ 108 ], or the ones that respond with fluorescence polarization [ 109 ]. Others such as SERS based [ 110 ] and CL aptasensors [ 111 ].…”

“…Fluorescent aptasensors, which can be categorized into aptasesnors that respond with fluorescent intensity [ 108 ], or the ones that respond with fluorescence polarization [ 109 ].…”

Characterization and stabilization in process development and product formulation for super large proteinaceous particles

“…Two populations can only be resolved if their particle diameters differ by at least 1.5‐fold [39]. However, NTA can also track nanoparticles by their fluorescence if adequate wavelength excitation lasers and emission filters are applied [47], providing the possibility for selective analysis of SLPPs. Recently, the fluorescent NTA analysis was employed to detect and quantify human respiratory syncytial virus (RSV) by using fluorescent dye conjugated specific receptor which binds selectively to the virus envelope [47].…”

Nanomaterial based aptasensors for clinical and environmental diagnostic applications

“…12,13 These receptors called aptamers (a term with Latin and Greek origins: aptus meaning t and meros meaning part) have shown notable moldable selectivity for diverse target analytes, ranging from small inorganic molecules, ions, sugars, proteins, and viruses to cells. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] Such a varied target range is lacking in antibody generation due to the restriction of target receptor exposure in their native forms. This is more evident in whole cells where the surface antigens contain certain hidden trans-membrane regions, a fact which is generally not accounted for during the maturation of antibodies.…”