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Flow cytometry has been used to study dilution-induced changes in the light scattered by the
phytoplankter D. tenioZecta (Ackleson et aZ., 1988). The data show large changes in side
scatter at nearly constant cell volume within less than an hour after a large change in the
suspension cell concentration. Another group has developed a theoretical model to explain the
changes in forward scatter observed when lymphocytes undergo osmotic shock (Sloot et aZ.,
1988).
Flow cytometric forward scattering and orange chlorophyll fluorescence were used to identify
a new prochlorophyte that is abundant in the ocean euphotic zone (Chisholm et aZ., 1988).
Button and Robertson (1989) used forward scattering in a flow cytometer to assist in
measuring the kinetics of nutrient uptake by microorganisms.
SUMMARY AND CONCLUSION
The physical phenomenon of light scattering is presented in terms of collections of tiny dipoles
being excited by the incident light and reradiating the light toward a detector. The scattered
wavelets are summed taking into account the phase relationships among them. Linear and
circular polarization concepts are introduced. The scattering matrix formalism is presented.
The coupled dipole approximation for modelling the scattering from irregularly shaped objects
is discussed in some depth and examples given comparing this approximation to Mie theory,
a exact model for homogeneous spheres and cylinders. The concept of phase differential
scattering is introduced as a method for making measurements of a combination of interesting
scattering matrix elements. Finally, several examples are given of the use of scattered light
polarization measurements in flow cytometry.
A brief review is then given of some of the other applications of forward and perpendicular
light scattering from cells in flow cytometers. These include measurements of refractive index
and the effects of osmotic shock, among others.
Flow cytometric light scattering is a useful tool to assist aquatic scientists in understanding
the cells they are studying. However, care must be exercised in interpreting the results oflight
scattering experiments.
Flow cytometry has been used to study dilution-induced changes in the light scattered by the
phytoplankter D. tenioZecta (Ackleson et aZ., 1988). The data show large changes in side
scatter at nearly constant cell volume within less than an hour after a large change in the
suspension cell concentration. Another group has developed a theoretical model to explain the
changes in forward scatter observed when lymphocytes undergo osmotic shock (Sloot et aZ.,
1988).
Flow cytometric forward scattering and orange chlorophyll fluorescence were used to identify
a new prochlorophyte that is abundant in the ocean euphotic zone (Chisholm et aZ., 1988).
Button and Robertson (1989) used forward scattering in a flow cytometer to assist in
measuring the kinetics of nutrient uptake by microorganisms.
SUMMARY AND CONCLUSION
The physical phenomenon of light scattering is presented in terms of collections of tiny dipoles
being excited by the incident light and reradiating the light toward a detector. The scattered
wavelets are summed taking into account the phase relationships among them. Linear and
circular polarization concepts are introduced. The scattering matrix formalism is presented.
The coupled dipole approximation for modelling the scattering from irregularly shaped objects
is discussed in some depth and examples given comparing this approximation to Mie theory,
a exact model for homogeneous spheres and cylinders. The concept of phase differential
scattering is introduced as a method for making measurements of a combination of interesting
scattering matrix elements. Finally, several examples are given of the use of scattered light
polarization measurements in flow cytometry.
A brief review is then given of some of the other applications of forward and perpendicular
light scattering from cells in flow cytometers. These include measurements of refractive index
and the effects of osmotic shock, among others.
Flow cytometric light scattering is a useful tool to assist aquatic scientists in understanding
the cells they are studying. However, care must be exercised in interpreting the results oflight
scattering experiments.