HPLC法测定物质含量.pdf

572 Chromatography absorbance reading of O. 3 to O. 7 where the experimental examine both of there absorptions at the specific error is the smallest. The width of the spectral slit must be wavelength.using suitable reagent as blank. Calculate the smaller than 1/1 0 of the half-width of the absorption concentration of solution being examined as method (1) band ,otherwise.low absorbance will be resulted. The slit described abovc width is appropriate if further reduction does not result in Unless otherwise specified. the blank used in this an increase of the absorbance reading. The absorbance of colourimetry method is the substrate using an equal volume an unmatched cell with the solvent concerned as a blank of solvent for the reference of the solution being must be subtracted from the absorbance of the substance examined. then in turn relative magents with equal quantîty being examined or be automatically deducted by the are added. then treated with the same method spectrophotometer When the pH value affects the results determined ,the pH vaJuc of the test solution should be adjusted equal to that of reference solution. 1. Identification and quaUty t四ts Carry out the method Chromatography described in the ivdividual monograph 2. Assay Carry out the methods as the following Depending on the mechanism of the separation process. (1) Reference substan四 comp町i皿D method Prepare chromatography can be classified into adsorption separately the test and the reference solution according to chromatography ,partition chromatography. ion-exchange the method