Ryan V, Hart T R, Schiller R
Biophys J. 1980 Sep;31(3):313-24. doi: 10.1016/S0006-3495(80)85061-2.
We have performed three different optical experiments to determine the mean size of the bacterial strain Streptococcus mutans 10449, a microorganism with dimensions comparable to the wavelength of the light used in our experiments. The three optical measurements give size values which are consistent with one another and favorably comparable to the consistency we found in identical measurements on a test system of polystyrene spheres of dimensions similar to the bacteria. Homodyne time correlation and power spectrum spectroscopy both depend on the coherence and monochromaticity of laser light for the determination of the mean diffusion coefficient of the scatterers. The Stokes-Einstein equation then relates the diffusion constant to the cell size. Differential light scattering relies for the interpretation of experimental data on the classical theoretical analysis of the angular distribution of scattered light from a scattering object. The three methods yield mean values for the radius of S. mutans 10499 of 0.324 +/- 0.006 mum, 0.0325 +/- 0.007 mum, and 0.315 +/- 0.009 mum, respectively. However, since intensity correlation spectroscopy provides a direct measure of polydispersity, it would appear to be the preferred single measurement technique for size determination.
我们进行了三项不同的光学实验，以确定变形链球菌10449菌株的平均大小，该微生物的尺寸与我们实验中使用的光的波长相当。这三项光学测量给出的尺寸值相互一致，并且与我们在尺寸与细菌相似的聚苯乙烯球体测试系统的相同测量中发现的一致性相比，具有良好的可比性。零差时间相关和功率谱光谱法都依赖于激光的相干性和单色性来确定散射体的平均扩散系数。然后，斯托克斯 - 爱因斯坦方程将扩散常数与细胞大小联系起来。差分光散射依赖于对散射物体散射光的角分布的经典理论分析来解释实验数据。这三种方法分别得出变形链球菌10499半径的平均值为0.324±0.006微米、0.0325±0.007微米和0.315±0.009微米。然而，由于强度相关光谱法提供了多分散性的直接测量，它似乎是用于尺寸测定的首选单一测量技术。
