Unusual sequence length-dependent gold nanoparticles aggregation of the ssDNA sticky end and its application for enzyme-free and signal amplified colorimetric DNA detection
نویسندگان
چکیده
It is known that the adsorption of short single-stranded DNA (ssDNA) on unmodified gold nanoparticles (AuNPs) is much faster than that for long ssDNA, and thus leads to length-dependent AuNPs aggregation after addition of salt, the color of the solutions sequentially changed from red to blue in accordance with the increase of ssDNA length. However, we found herein that the ssDNA sticky end of hairpin DNA exhibited a completely different adsorption behavior compared to ssDNA, an inverse blue-to-red color variation was observed in the colloid solution with the increase of sticky end length when the length is within a certain range. This unusual sequence length-dependent AuNPs aggregation might be ascribed to the effect of the stem of hairpin DNA. On the basis of this unique phenomenon and catalytic hairpin assembly (CHA) based signal amplification, a novel AuNPs-based colorimetric DNA assay with picomolar sensitivity and specificity was developed. This unusual sequence length-dependent AuNPs aggregation of the ssDNA sticky end introduces a new direction for the AuNPs-based colorimetric assays.
منابع مشابه
An enzyme-free and amplified colorimetric detection strategy: assembly of gold nanoparticles through target-catalytic circuits.
Herein we introduce an enzyme-free and amplified colorimetric detection strategy, which is based on gold nanoparticle (AuNP) aggregation through target-catalytic DNA circuits (HCR and CHA).
متن کاملLabel-Free Colorimetric Detection of Specific Sequences in PCR amplified DNA
We observed that single-stranded DNA adsorbs on negatively charged gold nanoparticles (Au-nps) and the adsorption rate is sequence length dependent. We also found that the adsorption stabilizes the Au-nps against salt-induced aggregation. Based on these observations, we developed a simple, rapid and cost efficient colorimetric assay to identify specific sequences in PCR amplified DNA. The assay...
متن کاملAssessing Stability of Gold Nanoparticles in Presence of Two Enzymes, RNaseA and RNaseH, Using Colorimetric Detection
Gold nanoparticle-based diagnostic methods have attracted much attention due to their simplicity, high sensitivity and low cost. These methods are mostly used for early and efficient detection of various pathogenic factors and assessment of gene expression and nanoparticles stability. In this study, melon plants were cultured in vivo and then, RNA was extracted from leaf explants. A 40 bp probe...
متن کاملDNA Biosensor for Determination of 5-Fluorouracil based on Gold Electrode Modified with Au and Polyaniline Nanoparticles and FFT Square Wave Voltammetry
In the present study, a new biosensor for 5-Fluorouracil was described using modified goldelectrode and Fast Fourier transform square wave voltammetry (FFT SWV). Calf thymus DNAimmobilization was on a gold electrode decorated with polyaniline and gold nanoparticles. Theelectrochemical characteristics of the electrodes were investigated by cyclic voltammetry, andelectroch...
متن کاملSimple and rapid colorimetric sensing of enzymatic cleavage and oxidative damage of single-stranded DNA with unmodified gold nanoparticles as indicator.
The sequence-length-dependent adsorption of single-stranded DNA (ssDNA) on unmodified gold nanoparticles is exploited as a new mechanism for colorimetric nuclease assay and measurement of oxidative DNA damage.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 6 شماره
صفحات -
تاریخ انتشار 2016