تسجيل الدخول

تسجيل

Quantitative analysis , Fundamental basis

المؤلف:  Sue Jickells , Adam Negrusz (Editors)

المصدر:  Clarkes Analytical Forensic Toxicology

الجزء والصفحة:  410

2026-11-09

53

Quantitative analysis

Fundamental basis

The basic principle of most spectrophotometric measurements involves comparing, under well-defined conditions, the absorption of radiation by the substance in an unknown amount with the same absorption of radiation by a known amount of the material being determined. In general, to obtain the maximum sensitivity it is best to work with radiation of a wavelength that is approximately equal to that for which the solution exhibits a maximum selective absorption. Assuming that the linear range for compliance with the Beer–Lambert law has been established and that the drug concentration has been adjusted within the optimum range for the type of instrument concerned, two approaches to quantification may be employed:

• reference standards

• specific absorbance.