Fig. 2

Principles of LAMP assay. The auto-cycling stage: After the self-hybridizing reaction dissociate the stem-loop structure in the 5′ end, an inner primer hybridized to the stem-loop in the 3′ end, initiating the auto-cycling stage. The newly synthesized 3′ end continues its self-hybridizing reaction, producing a stem-loop DNA essentially identical with the initial one and a new one with the stem twice as the original one. Inner primers hybridizes, elongating new strands once there is a stem free thus to repeat the aforementioned reaction. The final products in (g), namely stem-loop DNAs of varied sizes and cauliflower-like structures with multiple loops, accumulates as long as the reaction circularly continues