The ninhydrin reaction was negative , but when the preparation was hydrolyzed with 12n hc1 at 110 for 24h , it became positive 茚三酮反应呈阴性，但在110酸解后反应又呈阳性。
2.
Colorless materials can be used if some means of detecting them is used ( electronic detection , radioactive labeling , or ninhydrin developer ) 如果运用一些其他的检测方法（电子检测，放射性标记，茚三酮等）无色的物质也可以使用。
3.
The metabolite is soluble in water and insoluble in the organic solvent such as methanol , can be precipitated by acid , is positive with ninhydrin reaction and is considered as a kind of peptide 此物质溶于水，不溶于甲醇，可被酸沉淀，茚三酮反应为阳性，初步推断此活性物质为多肽类物质。
4.
Immobilization of polylysine ( pll ) onto hec and chitosan - coated membranes via activation reagents provided pll affinity membrane , respectively . a simple method for quantitative analysis of solid chitosan based on the ninhydrin reaction was achieved by diluting the reaction solution with 50 % ( v / v ) 以高浓度的茚三酮显色液与固体壳聚糖反应，再采用乙醇水溶液稀释反应液的方法，解决了固载在基材上壳聚糖含量的测定问题。
