Two-dimensional black phosphorus photoelectrochemical electrode based on DNA modification, preparation method and application

Abstract

The invention belongs to the technical field of photoelectrochemical biosensors, and discloses a two-dimensional black phosphorus photoelectrochemical electrode based on DNA modification, a preparation method and an application. 4-azidobenzoic acid is modified on a surface of black phosphorus in a covalent bond functionalization mode, and a 4-AB-BP thin film is deposited on a surface of the ITO electrode through a dropwise coating method; and sulfo-NHS / EDC condensation on an amino group connected with a 5'end of ligand and a carboxyl group of benzoic acid is carried out to prepare aptamer covalent functionalized modified black phosphorus ITO, and a molar ratio of black phosphorus to 4-azidobenzoic acid is 1: 6. The method is advantaged in that the covalent functionalized black phosphorus is applied to a photoelectrochemical biosensor for the first time, compared with an existing black phosphorus biosensor, the 4-azidobenzoic acid is used for modification, the service life of the blackphosphorus can be prolonged, the aptamer is bonded to the black phosphorus through the covalent bond, the service life of the black phosphorus modified ITO electrode is prolonged, and sensitivity of the black phosphorus modified ITO electrode is improved.

Description

technical field [0001] The invention belongs to the technical field of photoelectrochemical biosensors, and in particular relates to a DNA-modified two-dimensional black phosphorus photoelectrochemical electrode, a preparation method and an application, and specifically relates to two different principles but both are based on DNA-modified two-dimensional black phosphorus photoelectrochemical electrodes. Design, preparation methods and applications. Background technique [0002] At present, photoelectrochemistry is a discipline that studies how to induce redox reactions of solution components by utilizing the separation of photogenerated carriers at the semiconductor and solution interfaces. Sensors constructed on the basis of photoelectrochemical principles have been used in chemical and biological detection and other fields because of their high sensitivity, low background signal interference, low detection limit, low cost, and easy miniaturization. [0003] The problems ...

AI Technical Summary

Problems solved by technology

[0003] The problems in the existing technology are: (1) The existing multi-binding enzyme-linked immunosorbent assay technology takes a long time to test and cannot realize instant detection, so it is not suitable for patients to do it themselves Detect anytime and anywhere, limiting the market promotion of photoelectrochemical biosensors

[0004](2) The quantum efficiency and carrier mobility of existing photosensitive materials are low, which limits the photocatalytic redox reaction rate, resulting in low photocurrent generation rate , the sensitivity of the biosensor is not high

[0005](3) Existing photosensitive materials have narrow absorption bands and infrared absorption peaks, resulting in the need for sensors to integrate infrared light sources, increasing the size, complexity and manufacturing costs of sensors

[0006](4) Most of the existing photoelectrochemical detection methods are limited to the steric hindrance effect generated at the anode after immobilizing biomarkers (biomolecules) to hinder photoelectrochemical The transport of electrons in the reaction, thereby blocking the photoelectrochemical reaction, to achieve the purpose of detection

This method is prone to false positive test results

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