Spectrophotometry is a technique that allows scientists to identify
substances without ever having to actually touch them. A substance can be
in a sealed glass container and still be identified as long as light is able
to shine through it. This is particularly useful for substances that may be
dangerous or highly toxic. Also, spectrophotometry is useful for
identifying gases, which must be kept in sealed containers.
Spectrophotometry is used in a variety of scientific research projects and
bioassays. As shown in the absorption spectra of chlorophyll a and b in
the exercise in the lab manual, spectrophotometry is used to discern between
the various pigments found in plant cells. In medical technology,
spectrophotometry is used to determine the seriousness of a heart attack by
taking an enzyme from the blood of a patient and comparing it to a standard
curve.
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2002 McGraw-Hill Higher Education