Process for producing low-toxicity fluorescent carbon point

Abstract

The invention provides a preparation method for a low-toxic fluorescence carbon point. The method comprises the steps as follows: a washed carbon electrode is added into an electrolyte liquid and oxidation is carried out on the carbon electrode by a constant potential electrolytic oxidation method at a more positive potential position; then the carbon electrode after being oxidized is washed by ultra-pure water; the water liquid after washing is collected; the electrolyte liquid and the water liquid after washing are combined and centrifugated for collecting supernatant and removing the deposits; finally the collected supernatant is filtered in sequence by ultrafilter pipes the retained molecular weights of which are respectively 30, 10 and 5kDa; the components with the retained molecular weights of 5-10kDa and less than 5kDa are collected, wherein, the component of the retained molecular weight of 5-10kDa is the carbon point which gives out yellow fluorescence; and the component less than 5kDa is the carbon point which gives out blue fluorescence. The method is simple and easy to carry; the material resources are broad and cheap; and the obtained carbon points do not have cytotoxicity and resist light bleaching.

Description

Technical field [0001] The invention relates to a method for preparing low-toxic fluorescent carbon dots, and belongs to the field of chemistry and material science. Background technique [0002] In recent years, fluorescent semiconductor quantum dots, due to their unique fluorescent properties (such as strong fluorescence intensity and wide excitation wavelength range, can achieve single-element excitation and multiple emission, the emission peak half-width is very narrow (about 20nm), emission wavelength is controllable, and light drift resistance Etc.) and has attracted much attention, and has been widely used in cell imaging, biological labeling, nucleic acid analysis and detection, protein analysis and detection, ion probes, etc. However, the fluorescent semiconductor quantum dots currently used are mainly composed of II B and VI A elements such as: CdSe@ZnS, CdTe, etc., Cd 2+ The existence of posed a potential threat to the environment. Although the quantum dots are not tox...

AI Technical Summary

Problems solved by technology

The nitric acid oxidation method is time-consuming and the prepared carbon dots are not easy to separate, the fluorescence quantum yield is very low, and the half-peak width of the fluorescence spectrum is wide

The only suitable material for electrochemical cyclic voltammetric oxidation is carbon nanotubes, which are expensive and can only be prepared in an organic phase, and only one color of fluorescent carbon dots can be obtained.