Protein-matrix microlens array diffraction device and method for preparing the same

A method for preparing a protein-matrix microlens array diffraction device, comprising the following steps:

• (1) preparing a protein crystal, comprising:
• (1-1) mixing a protein solid with a solution having a concentration of a salt, comprising sodium chloride and sodium acetate, of 2% to 5% by mass to obtain a protein solution, wherein a mass fraction of the protein in the protein solution is 1 to 3 times a mass fraction of a saturated solution, and the protein solution is adjusted to have a pH of 4 to 6;
• and
• (1-2) placing the protein solution obtained from step (1-1) in a container and leaving the protein solution to stand at a room temperature for a period of 6 to 24 h, wherein during the period water of the protein solution is naturally evaporated, thereby obtaining the protein crystal,
• and
• (2) emitting a femtosecond laser on a surface of the protein crystal obtained in step (1), wherein the femtosecond laser has a pulse duration of 35 to 120 fs, a single pulse energy of the femtosecond laser is half of a protein ablation threshold, and the femtosecond laser has a repetition frequency of 1 to 1000 Hz.