Qualitative nucleic acid detection method based on nanoparticles and rolling circle amplification

Abstract

The invention provides a nucleic acid qualitative detection method based on nano-particles and rolling circle amplification. The detection method mainly comprises the steps of: allowing silica nanoparticles in a disperse state in a solution before the rolling circle amplification is used; performing the rolling circle amplification when a target nucleic acid molecule is present; and gathering the silica nanoparticles to form a macroscopic white blocky substance in the solution so as to achieve the purpose of qualitatively detecting the target nucleic acid molecule. As the presence of the target nucleic acid molecule can be judged by gathering states of the silica nanoparticles before and after rolling circle amplification, a large number of trace nucleic acid molecules are amplified, results are rapidly and intuitively detected without a special detection instrument, the detection cost is reduced, and the nucleic acid qualitative detection method is suitable for popularization of clinical detection.

Description

technical field [0001] The invention belongs to the field of detection of nucleic acid molecules, and in particular relates to a method for quickly and simply realizing the qualitative detection of nucleic acid molecules by utilizing the change in particle aggregation form before and after rolling circle amplification on the surface of silica nanoparticles. Background technique [0002] Rolling circle amplification (RCA) is a newly developed isothermal nucleic acid amplification method. Using circular DNA as a template, dNTPs are converted into single-stranded DNA under the catalysis of a special DNA polymerase (phi 29 DNA polymerase) through a short DNA primer (complementary to a part of the circular template). Its linear amplification factor is 10 5 , the exponential amplification ability is greater than 10 9 , realize the signal amplification of the target nucleic acid, and the sensitivity reaches one copy of the nucleic acid molecule, which has great application value ...

AI Technical Summary

Problems solved by technology

At present, there are two general methods. One is to use gold or silver nanoparticles to modify nucleic acid probes to detect target nucleic acid molecules according to the color change of the solution. The advantage is that the detection method is simple, but the cost of the nanoparticles used is relatively high; The other is to modify nucleic acid molecules on the surface of the particles, and then add fluorescent probes to detect target molecules through different nucleic acid amplification methods. The advantage is that the detection sensitivity is relatively better, but the cost of fluorescent probes is also high.

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