is 1-10 mg protein hydrolyzate in flat-bottom microplate

Ninhydrin-based assay method is based on the calculation of the total amino acids following acid hydrolysis of protein in the sample network. Microtitre plates used in this test. Tissue samples (10 mg) was first hydrolyzed in 500 ml 6 M HCl at 100 C for 24 h to liberate ammonia. Example and then lyophilized (cooled and evaporated), and the rest with ammonium chloride, used in a known volume of water.

Ninhydrin with ninhydrin reagent, ethylene glycol, acetate buffer, and tin-suspension, which was originally a bright red, is 1-10 mg protein hydrolyzate in flat-bottom microplate. During the 10-min incubation at 100 C, ammonia reacts with ninhydrin reagent to diketohydrin dylidenediketohydrindamine.

Under these conditions, the product of broad absorption band 560-580 nm and 575 nm microplate reader to be used for measurement. The correlation of absorbance with protein concentration of different protein standards, as shown in Figure, which also shows the same results with a protein from the standard method of Bradford. This data shows better sensitivity to the ninhydrin method, and suggest that approximately 10-fold improvement in detection limit. The important advantage of this method is that differences in the calibration curves, with a variety of standard protein is relatively low. Interference-free amino acids and other compounds containing amine groups.