Spectrophotometry is a quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. This depends upon how much light is absorbed by a chemical substance.
Measurement is done by recording the intensity of light absorbed as a beam of light passes through sample solution.
A spectrophotometer is an instrument used to quantitatively measure the transmission or reflection of visible light, UV light or infrared light.
Photometry is a science, which deals with the measurement of human visual response to visible light.
Why is it Important
It is one of the most useful tools available for research as it offers a high degree of precision, sensitivity, and accuracy.
This chapter deals with, an introduction to commonly used spectroscopic techniques, basic principles, their types, and their applications in investigation of structure, function and dynamics of biological system.
Difference between Spectroscopy and Spectrophotometry
Spectroscopy study deals with the transitions induced in a chemical species by its interaction with the photons of electromagnetic radiation.
Whereas, Spectrophotometry is a quantitative approach of measuring the relative energy i.e. emitted, transmitted or reflected in the visible or UV regions. It is a function of wave length or wave number.
Applications of Spectrophotometry
In biological science, everything from signaling pathways, in which proteins act, to the behavior of nucleic acids can be determined by spectrophotometry.
Some of the major applications of spectrophotometers include the following:
- Detection of concentration of substances
- Remote sensing
- Detection of impurities
- Structural analysis of organic compounds
- Monitoring dissolved oxygen content in freshwater and marine ecosystems
- Determination of species
- Studying biochemical processes
- Characterization of proteins
- Detection of functional groups
- Respiratory gas analysis
- Molecular weight determination of compounds
- The visible and UV spectrophotometer may be used to identify classes of compounds in both the pure state and in biological preparations.
Ballinger R. (1999). http://www.mritutor.org/mritutor/ [A tutorial on NMR imaging covering the basic principles and questions related to instrumentation, safety and contrast agents].