Expression of ScFv and purification of cdGIGPQc-ScFv. The recombinant plasmid pET-28a-ScFv was transformed into the E. coli BL21 (DE3). A: The recombinant plasmid pET-28a-ScFv confirmed by restriction analysis before transformation. B: After induction, purified ScFv protein extracted from bacteria was separated on a SDS-PAGE gel and stained with Coomassie Blue. Lane M, protein molecular mass markers (KDa); Lane BI, bacterial proteins before induction; Lane AI, bacterial proteins after induction; Lane p, the precipitation after sonication; Lane FT, the filtered proteins; Lane E1, E2, E3, the purified ScFv protein; Lane R, the renatured ScFv protein. C: SDS-PAGE analysis of cdGIGPQc-ScFv and cNAQAEQc-ScFv. Lane 1, 2, cNAQAEQc-ScFv; Lane 3, 4, cdGIGPQc-ScFv; Lane 5, protein molecular mass markers; Lane 6, the ScFv protein.