Abstract: The present disclosure belongs to the technical field of biosensors and particularly provides a construction method for a photocathode indirect competition sensor and an evaluation method. The construction method includes: using Z-type Bi2O3/CuBi2O4 as a sensing platform; calculating a photoinduced electron Z-type transfer path and an energy band structure of Bi2O3 and CuBi2O4 using a density functional theory (DFT); and constructing a Bi2O3/CuBi2O4-based biosensor. A photoelectrochemical (PEC) photocathode biosensor based on a Bi2O3/CuBi2O4 heterojunction prepared through the solution has good repeatability, reproducibility, stability, and specificity for detecting a target. The PEC biosensor constructed in the solution of the present disclosure has a broad application prospect in the fields of healthcare, environment, and food.

Abstract: The present invention relates to an early warning method before the occurrence of aflatoxin contamination.

Abstract: The present disclosure belongs to the technical field of biosensors and particularly provides a construction method for a photocathode indirect competition sensor and an evaluation method. The construction method includes: using Z-type Bi2O3/CuBi2O4 as a sensing platform; calculating a photoinduced electron Z-type transfer path and an energy band structure of Bi2O3 and CuBi2O4 using a density functional theory (DFT); and constructing a Bi2O3/CuBi2O4-based biosensor. A photoelectrochemical (PEC) photocathode biosensor based on a Bi2O3/CuBi2O4 heterojunction prepared through the solution has good repeatability, reproducibility, stability, and specificity for detecting a target. The PEC biosensor constructed in the solution of the present disclosure has a broad application prospect in the fields of healthcare, environment, and food.

Abstract: The present invention relates to an early warning method before the occurrence of aflatoxin contamination.

Abstract: The present invention relates to an aflatoxin contamination risk warning molecule and use thereof. The steps are as follows: weighing a quantitative sample, extracting the aflatoxin contamination risk warning molecule to obtain a sample extract, and detecting and analyzing the sample extract to obtain a quantitative result of the aflatoxin contamination risk warning molecule; performing modeling with a chemometrics method using the content of one or more of the aflatoxin contamination risk warning molecules as a variable to obtain a classification prediction model, and performing risk assessment on aflatoxin contamination risk of the sample based on the classification prediction model, wherein a warning molecule of an aflatoxin toxigenic strain is one or a combination of more than one of versiconol (VOH), versicolorin B (Ver B), and 5-methoxysterigmatocystin (5-MST).

Abstract: The invention belongs to the field of chemical analysis and detection, and specifically relates to a pretreatment method for LC-MS detecting metabolomics of Aspergillus flavus. The method includes: culturing a strain of Aspergillus flavus; quenching the Aspergillus flavus; disrupting the cell membrane of Aspergillus flavus, and extracting a metabolome. The invention adopts a cold glycerol buffer solution combined with a rapid filtration method for quenching, and a MeOH/DCM/ACN/EA/HCOOH mixture is used as an metabolome extract, thereby achieving the object of efficiently extracting different polar compounds, and metabolome compound coverage is high; pretreatment of the cell metabolomics of Aspergillus flavus by the method of the invention can ensure the repeatability and stability of the metabolomics analysis method and reduce the false positive of the test results.

Abstract: The invention belongs to the field of chemical analysis and detection, and specifically relates to a pretreatment method for LC-MS detecting metabolomics of Aspergillus flavus. The method includes: culturing a strain of Aspergillus flavus; quenching the Aspergillus flavus; disrupting the cell membrane of Aspergillus flavus, and extracting a metabolome. The invention adopts a cold glycerol buffer solution combined with a rapid filtration method for quenching, and a MeOH/DCM/ACN/EA/HCOOH mixture is used as an metabolome extract, thereby achieving the object of efficiently extracting different polar compounds, and metabolome compound coverage is high; pretreatment of the cell metabolomics of Aspergillus flavus by the method of the invention can ensure the repeatability and stability of the metabolomics analysis method and reduce the false positive of the test results.