Final answer:
A spectrophotometer is the most commonly used instrument to measure the concentration of tyrosine from absorbance readings.
Step-by-step explanation:
For the measurement of tyrosine concentration from absorbance, the instrument commonly used is a spectrophotometer. A spectrophotometer distinguishes itself as the tool of choice by its ability to measure transmitted light and calculate absorption. This measurement is crucial for establishing a standard curve in protein assays, which correlates absorbance readings with known protein concentrations, as well as for other applications such as determining the turbidity of a bacterial cell suspension or analyzing the levels of radioactive decay in geological samples.
In practice, a sample containing tyrosine would be placed in a spectrophotometer, and the specific absorbance related to the tyrosine content would be measured. This absorbance is often recorded at a specific wavelength—typically one where tyrosine has a peak absorption. The instrument settings, such as the wavelength (like 412 nm used in certain assays), and methodology are carefully selected based on the particular characteristics of the substance being measured and the details of the experimental procedure aiming to determine the substance's concentration.