Patent ID: 7157282

Claim:
A method of monitoring calibration of a spectrophotometric apparatus comprising one or more than one calibration algorithm for one or more than one analyte comprising: i) measuring absorbance of a quality control material with said apparatus to obtain a measurement, said quality control material exhibiting an absorbance spectrum characterized as having a negative slope for a quality control material (QCM) spectral segment of from about 5 nm to about 400 nm in length, or a wavelength there between, wherein said QCM spectral segment comprises wavelengths that overlap an observed analyte spectral segment for said one or more than one analyte, said observed analyte spectral segment characterized as having a negative slope of from about 5 nm to about 400 nm in length, or a wavelength there between; ii) calculating one or more than one value from said measurement using said one or more than one calibration algorithm; and iii) comparing said one or more than one value with an assigned value given to said quality control material for each of said one or more than one analyte, thereby monitoring said one or more than one calibration algorithm of said apparatus.