A Simple Colorimetric Method for Naked‐Eye Detection of Circulating Cell‐Free DNA Using Unlabelled Gold Nanoparticles

Abstract

Gaining interests and expediency of precision medicine for various diseases has led to the search for non invasive techniques like liquid biopsies involving study of circulating cell free DNA (cfDNA) for diagnostic as well as prognostic applications. Present study reports that cfDNA in plasma of patients with Rheumatoid Arthritis are fragmented, modified and hence remain undetected using qPCR, the commonly used analytical assay. They are immunogenic to peripheral blood cells and stimulate them to secrete TNF‐α, a pro‐inflammatory cytokine making it imperative to detect cfDNA in patients for an effective therapeutic intervention. Hereby a non‐invasive colorimetric assay for naked eye discernment of cfDNA using gold nanoparticles is proposed which is potent in detecting long and short cfDNA fragments from small amount of blood, is inexpensive, label free, easy to perform and allows visual detection. This can be further explored to assess its diagnostic and prognostics implications in various human disorders.

Gold Nanoparticles: Can They Be the Next Magic Bullet for Multidrug-Resistant Bacteria?

“…According to a recent literature review [ 29 ], gold nanoparticles in different dimensions and shapes are the most widely studied nanomaterials for antibacterial and anti-biofilm photothermal applications. Gold nanoparticles are now employed in many biomedical applications, including: bio-imaging, gene delivery, contrast enhancement of X-ray computed tomography, targeted drug delivery, diagnostics, plasmonic bio-sensing, colorimetric sensing, tissue engineering, photo-induced therapy, and cancer therapy [ 33 , 34 ].…”

Nanotechnology in emerging liquid biopsy applications

“…This system had an LOD of 7.7 fM, but it has not been applied to real samples [75]. Another colorimetric method involved the aggregation of unlabeled AuNPs, as AuNPs bound to isolated ctDNA from blood samples, resulting in a color change visualized by naked eye [76]. A lateral flow strip test was also developed for the detection of a specific mutation in ctDNA.…”

Role of gold nanoparticles in advanced biomedical applications

“…8 So far, the unique properties of GNPs have been exploited for many advanced biomedical applications (e.g., in vitro/in vivo use in bio-imaging, gene delivery, contrast enhancement of X-ray computed tomography, targeted drug delivery, diagnostics, plasmonic bio-sensing, colorimetric sensing, tissue engineering, photo-induced therapy, and cancer therapy). 9,10 Even though the medicinal applications of gold have been known to us since ancient human civilizations, recent advances in the eld of nanotechnology have further facilitated its use in the biomedical eld (e.g., biomedical imaging, targeted (site specic) drug delivery, and photoinduced therapeutic applications). 11,12 Generally, the physical and electronic properties of GNPs (and other gold nanostructures such as nanostars, nanorods, nanocages, nanoshells, and nanoprisms) are largely dependent upon their size and shape.…”

“…, in vitro / in vivo use in bio-imaging, gene delivery, contrast enhancement of X-ray computed tomography, targeted drug delivery, diagnostics, plasmonic bio-sensing, colorimetric sensing, tissue engineering, photo-induced therapy, and cancer therapy). 9,10 Even though the medicinal applications of gold have been known to us since ancient human civilizations, recent advances in the field of nanotechnology have further facilitated its use in the biomedical field ( e.g. , biomedical imaging, targeted (site specific) drug delivery, and photo-induced therapeutic applications).…”