Ninhydrin generally reacts with an amino group of amino acids.
Amino-N in the supernatant was determined using
ninhydrin with glycine as a standard (Rosen, 1957).
This study compares the effectiveness of three different lysochromes (Sudan III, Oil Red O, and Sudan black) to the fingerprint red (Dragon's Red), black, and silver metallic powders as well as to
ninhydrin in developing latent lip prints from long-lasting lipsticks on porous paper and cloth surfaces.
1)
Ninhydrin staining with histidine standards (Baker and Baker 1973).
In this system, amino acids were monitored spectrophotometrically after post-column reaction with
ninhydrin. Compositions of clam effluent and mantle fluid were almost identical (Pearson's product-moment correlation: [r.sup.2] = 0.998; P [less than] 0.001; n = 18 amino acids chromatographed), indicating that mantle fluid was the source of effluent material.
2 ml of the filtrate was collected, which was allowed to react with 2 ml acid
ninhydrin and 2ml glacial acetic acid.
But previous reports failed to provide a wide range of derivatives spiropyran based on a combination isatin,
ninhydrin and acenaphtheqinon.
A total of 0.5 g fresh tissue was homogenized in 5 mL 10% (w/v) acetic acid, extracts were supplemented with 1 mL distilled water and 3 mL
ninhydrin reagent, then boiled for 15 min and fast cooled, and the volume was made up to 5mL with 60% (v/v) ethanol.
[11] Rosen HA modified
ninhydrin colorimetric analysis for amino acids.
This method is also an improvement over traditional methods that apply ion exchange chromatography and postcolumn
ninhydrin derivatization, because allo-Ile at near normal concentrations is difficult to distinguish from other nearby eluting ninhydrin-sensitive amines, a complication that may be problematic in some cases (15).
Based on established post-column
ninhydrin based detection technology, the Biochrom 30 Amino Acid Analyser meets the requirements of the standard methods from the AOAC and the EU Commission Directive 98/64/EC.