Question

Describe how you will determine the affect of temperature on lipid membrane fludity in the Vesicle Transitions Using Fluorescence Polarization experiment.

Answer 1

Fluorescent polarization is a technique which is based upon difference in wavelength of the emitted light from a source when it is in motion and is stationary. This suggests that when a beam of light is focussed on a sample, say a plasma membrane, it will get excited and emitt light. On the other hand, when these molecules of plasma membrane are in motion, they will again emitt light but in a different wavelength. Thus, this difference in wavelengths describes the state of motion of the sample.

This can be also tested for analysis of the effect of temperature on plasma membrane. The simple experiment can be described as below:

1. Conduct an experiment in two steps, one set as control and another as experimental group.
2. Record the emittance spectra of the two membranes before any excitation by the temeprature.
3. Slowly raise the temperature of the second membrane and simultaneously record its emittance spectrum.
4. Plot a graph between the two sets of quantitative values.
5. The difference in these graphs will represent the extent of fluidity of the membrane and hence motion of the lipid biomolecuels in the membrane.

Thus, the trend of this graph can be observed to understand the effect of increasing temperature on motion of the lipid biomoleucles and hence the fluidity of the plasma membrane.