#### Is the first presenter a student?

No

#### Type of Submission

Paper/Presentation

#### Abstract

Indirect measurement of the amount of a specified component in a sample of a chemical compound can be accomplished by spectrophotometry. The underlying principle is Beer's Law, which states that, in a pure system, the amount of light absorbed by a chemical bond is linearly related to its concentration. In some mixtures it may not be possible to find a wavelength at which only the bond of interest absorbs light. Hence, the absorbance is composed of contributions from the bond of interest and one or more other (nuisance) bonds. Chemists refer to this situation as interference. In this paper we study the effect of ignoring interference and develop a statistical version of a deterministic approach used by chemists to account for interference. The results are discussed in the context of the measurement of two starch polymers in rice.

#### Keywords

Calibration; Inverse prediction; Regression

#### Creative Commons License

This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

STATISTICAL ANALYSIS OF SPECTROPHOTOMETRIC ASSAYS IN THE PRESENCE OF INTERFERENCE

Indirect measurement of the amount of a specified component in a sample of a chemical compound can be accomplished by spectrophotometry. The underlying principle is Beer's Law, which states that, in a pure system, the amount of light absorbed by a chemical bond is linearly related to its concentration. In some mixtures it may not be possible to find a wavelength at which only the bond of interest absorbs light. Hence, the absorbance is composed of contributions from the bond of interest and one or more other (nuisance) bonds. Chemists refer to this situation as interference. In this paper we study the effect of ignoring interference and develop a statistical version of a deterministic approach used by chemists to account for interference. The results are discussed in the context of the measurement of two starch polymers in rice.