The invention discloses a purification method for removing endotoxin in
prokaryotic expression recombinant
protein, which belongs to the technical field of bioengineering, and comprises the following steps: adding 0.1% Triton X-114 in an ultrasonication stage, carrying out ice-bath ultrasonication, after the recombinant
protein is combined with a Ni-NTA affinity column, washing with 50 column volumes of a combination
buffer solution containing 0.1% Triton X-114, and carrying out
elution by using an
elution buffer solution containing 0.1% Triton X-114 in the presence of an
elution buffer solution containing 0.1% Triton X-114 in the presence of an elution buffer solution containing 0.1% Triton X-114 in the presence of an elution buffer solution containing 0.1% Triton X-114; and washing with a 4-DEG C binding buffer solution with 20 column volumes, and subsequently eluting the
target protein with
imidazole with different gradients. Then, regulating the pH value of the purified recombinant
protein solution to 2-4 or more than 10 through 100mM
hydrochloric acid or
sodium hydroxide, dissociating and decomposing endotoxin, carrying out oscillation treatment at
room temperature for 2-4 hours, then removing the endotoxin in the recombinant protein through
ultrafiltration, retaining an endotube
protein solution, and detecting the content of protein and the endotoxin in the recombinant protein; the method is easy and convenient to operate and low in cost, the endotoxin content in the recombinant protein prepared through
prokaryotic expression can be reduced by 400 times on the premise that
immune recognition of the recombinant protein and serum is not affected, and the phenomenon that strong cross reaction occurs between immune serum and
escherichia coli due to high endotoxin residues in the recombinant protein is reduced.