[Establishment of a purificatory method for alpha-fetoprotein variant by affinity adsorption].

Objective: To establish a purificatory method of alpha-fetoprotein variant (AFP-L3) based on microspincolumn with lens culinaris agglutinin (LCA).

Methods: LCA was isolated by ammonium sulfate precipitation method from lens culinaris. AFP-L3 affinity adsorption microspincolumns which were made from LCA coupled with activated Sepharose 4B were prepared. By adding into the centrifuge column, serum was absorbed and eluted to purify AFP-L3. The results of purified AFP-L3 detection of 10 cases AFP positive sera by electro-chemiluminescence immunoassay were compared with traditional crossed affinity immunoelectrophoresis.

Results: 8 of 10 cases AFP-L3 concentration were greater than 5 ng/ml in purified sera. Six cases show positive reaction in affinity immune cross electrophoresis experiment.

Conclusion: Successfully established purification method of AFP-L3 by affinity absorption based on microspincolumn. The method was more conducive to clinical laboratory applications due to its high sensitive and easy operation.