This ninhydrin solution reacts with amino acids present in sweat and turns purple due to the formation of Ruhemman's purple.

这种溶液与汗液中氨基酸发生反应，由于鲁赫曼紫形成而变成紫色。

For porous surfaces like paper or walls, fingerprints are detected by spraying a solution called ninhydrin on the surface where a print may be found.

对于像纸或墙这样表面，通过在可能发现指纹表面喷洒一种叫做溶液来检测指纹。