Patent ID: 6818450
Filing Date: 2004-11-16
Classification: C07F,G01N,Y10T

Abstract:
A method for determining the concentration of an analyte of an aqueous mixture comprising N-(phosphonomethyl)iminodiacetic acid, a salt of N-(phosphonomethyl)iminodiacetic acid, an ester of N-(phosphonomethyl)iminodiacetic acid), N-(phosphonomethyl)glycine, a salt of N-(phosphonomethyl)glycine, an ester of N-(phosphonomethyl)glycine), formaldehyde, formic acid, N-methyl-N-(phosphonomethyl)glycine, N-methyl-aminomethylphosphonic acid, aminomethylphosphonic acid, or mixtures thereof, the method comprising:measuring an electromagnetic absorbance spectrum for the aqueous mixture over an infrared wavenumber range of from about 200 cmâˆ’1 to about 5000 cmâˆ’1 using a Fourier transform infrared spectrometer which uses an internal reflectance sensor to sample the electromagnetic absorbance of the mixture, the internal reflectance sensor being an attenuated total reflectance probe having a sampling surface comprising diamond; and using data from the electromagnetic absorbance spectrum in a chemometric model to determine the concentration of the analyte in the aqueous mixture, the chemometric model being a mathematical relationship between the concentration of the analyte in the aqueous mixture as a function of the electromagnetic absorbance spectrum of the mixture.