Bioanalytical Chemistry
Chapter One
Spectroscopic Methods for
Matrix Characterization
1.1. INTRODUCTION
The objective of many bioassay methods is to selectively quantitate a single biomolecule,
such as a particular enzyme or antibody, or to determine the presence or
absence of a known DNA sequence in an unknown sample. Methods for these
very selective assays will be considered in later chapters.
When faced with a true unknown, for example, during the isolation or purification
of a biomolecule, it can be important to characterize the unknown matrix, or
the components in the unknown solution that are present along with the species of
interest. This involves the estimation of the total quantity of the different types of
biomolecules.
Biochemists often estimate the total quantity of protein and nucleic acid in an
unknown by the nomograph method. In this method, the absorbance of the
unknown solution in a 1-cm cuvette is measured at 260 and 280 nm. The nomograph
(Fig. 1.1) is then used to estimate concentrations.
The nomograph method is rapid and involves no ch ... read full excerpt from Bioanalytical Chemistry ebook
