Method for synthesizing dye modified DNA (Deoxyribonucleic Acid) functionalized cadmium-containing quantum dots and application of quantum dots

Abstract

The invention discloses a method for synthesizing dye modified DNA (Deoxyribonucleic Acid) functionalized cadmium-containing quantum dots and an application of the quantum dots. According to the quantum dots, DNA, of which one end is modified with a dye and the other end is modified with thiophosphate, is connected to surfaces of the quantum dots through strong interaction between sulfur and cadmium. During the synthesis of the quantum dots, the dual-modified DNA is added as a co-stabilizer of the quantum dots so as to obtain a quantum dot probe. The quantum dot probe has extensive use in the aspect of ratio fluorescence, can be used for achieving accurate detection on nucleic acids, proteins, micromolecules and metal ions and has an important application value in the aspects of DNA hybridization and nano-material self-assembly. Meanwhile, as a whole body, the probe can be applied to the aspects of cell recognition, tumor targeted detection and the like as a fluorescence imaging probe. Compared with other dual-fluorescence-emission nano-materials, the probe has the advantages that the preparation method is simple, chemical modifications such as coupling are not required, and the probe has considerable advantages in the aspects of synthesis and purification processes, stability and other properties.

Description

Technical field [0001] The invention relates to the fields of nanomaterials and biomedical analytical chemistry, in particular to a method for synthesizing dye modified DNA to functionalize cadmium-containing quantum dots and its application. Background technique [0002] Quantum dots, also known as semiconductor nanocrystals, are zero-dimensional nanomaterials with a diameter of 1-100 nm. Cadmium-containing quantum dots are one of the most commonly used quantum dots, with high quantum yield, adjustable emission wavelength and good stability. There are more and more researches in the fields of optoelectronic materials, molecular biology and biomedical analysis. DNA functionalized quantum dots have more extensive applications in biological detection, imaging and nanomaterial self-assembly. [0003] There are many methods for synthesizing single-wavelength DNA functionalized quantum dots, such as: 1. linking biotin-modified DNA to avidin-modified quantum dots; 2. chemically coupling...

AI Technical Summary

Problems solved by technology

The cost of the above methods is very high, the preparation process is cumbersome, the conditions are harsh, and they are easy to affect the luminous efficiency of quantum dots

In 2009, Ma Nan et al. connected phosphorothioate-modified DNA to the surface of quantum dots through the interaction of sulfur and cadmium. This method simultaneously carried out DNA functional modification during the synthesis of quantum dots, which simplified the preparation process and reduced the need for The effect of quantum dot performance (N. Ma, et al, Nat. Nanotechnol. 2009, 4,121-125), but the DNA functionalized CdTe quantum dots synthesized by them have high cytotoxicity and low quantum yield

Ma et al. used electrostatic interaction to combine an imidazole dye with quantum dots to construct a ratiometric fluorescent probe, but the electrostatic interaction is not strong, so the probe is susceptible to environmental influences (F. Ma, et al, Sensors and Actuators B: Chemical, 2015, 209, 377-383)

Most of the above methods connect two or more fluorescent materials together through one-step or multi-step coupling reactions. The whole preparation process is very cumbersome, time-consuming, and has a great impact on the fluorescent properties of the materials.

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