Method for detecting an okadaic acid based on a near-infrared photoelectric composite material

A method for detecting okadaic acid based on near-infrared photoelectric composite material, wherein the following steps are comprised:

• Step S1:
• mixing okadaic acid monoclonal antibody and a phosphate buffer saline at a mass ratio of 1:1000-3000 to obtain a solution A;
• Step S2:
• dispersing polyethyleneimine/NaYF4:
• Yb, Tm in a phosphate buffer containing 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and N-hydroxy succinimide to obtain a solution B;
• Step S3:
• mixing and reacting the solution A and the solution B to obtain a solution C, and dispersing a precipitate after centrifugation of the solution C in a phosphate buffer containing bovine serum albumin to obtain a target product NaYF4:
• Yb, Tm-Ab;
• Step S4:
• dissolving flower-like tungsten oxide and chitosan in ultrapure water to obtain a flower-like tungsten oxide/chitosan suspension D;
• Step S5:
• dropping the flower-like tungsten oxide/chitosan suspension D on a screen-printed carbon electrode to obtain a target product of a flower-like tungsten oxide/chitosan/screen-printed carbon electrode;
• Step S6:
• adding an okadaic acid into a 2-morpholinoethanesulfonic acid biological buffer to obtain a solution E, and immersing the flower-like tungsten oxide/chitosan/screen-printed carbon electrode obtained in step S5 into the solution E for reaction;
• Step S7:
• reacting the flower-like tungsten oxide/chitosan/screen-printed carbon electrode obtained in step S6 in an acetamide solution and a bovine serum albumin solution containing Tween-20, respectively, to obtain a target product of okadaic acid toxin/flower-like tungsten oxide/chitosan/screen-printed carbon electrode;
• Step S8:
• casting a diluted solution of NaYF4:
• Yb, Tm-Ab and an okadaic acid standard solution on the okadaic acid/flower-like tungsten oxide/chitosan/screen-printed carbon electrode for reaction, and performing rinsing with a phosphate buffer saline containing Tween-20 after reaction;
• and
• Step S9:
• setting a bias voltage to 0 V using a chronoamperometry to test a photoelectric behavior of the okadaic acid/flower-like tungsten oxide/chitosan/screen-printed carbon electrode obtained in step S8.