PPT Slide
 
 
TECHNIQUE #3 Doping or Spiking Method
Sample to be analysed is spiked with known amount of the analyte phase J
-  	Weight fraction of phase J in spiked sample
 
	M = mass sample						MJD = mass dopant phase J					xJM =  mass of phase J in undoped sample 		 	xJD = weight fraction of dopant = MJD / (M + MJD)
(xJ)D  =  (xJM + MJD) / (M + MJD)  =  xJ (1 - xJD) + xJD