Fig 5.

Comparison of sensitivity of loop-mediated isothermal amplification (LAMP) to nested PCR. Lane M, 100 bp DNA ladder marker (Roche Applied Science); tubes and lanes 1-7, reactions contained 10⁵, 10⁴, 10³, 10², 10¹, 10, and 10^-1 cultured promastigote of L. infantum per 1 ml blood, respectively; lane 8, negative control (PCR grade water). (A) Detection limit of the LAMP reaction based on color change in SYBR Green I by the naked eye under visible light: The color of positive reactions (tubes1–6) became bright green while the color of the negative reactions (tubes7–8) remained unchanged (orange). (B) Detection limit of the LAMP reaction using electrophoresis of 2 μl of each reaction mixture in 2% agarose gel followed by ethidium bromide staining: lanes 1–6 showed the typical ladder-shaped pattern of a positive reaction. (C) Sensitivity of the nested PCR and producing a 680-basepair fragment