Kirichenko M N, Shkirin A V, Chaikov L L, Simakin A V, Tcherniega N V, Gudkov S V
Lebedev Physical Institute of the Russian Academy of Sciences, Leninskiy prospekt, 53, Moscow, 119991, Russia.
Prokhorov General Physics Institute of the Russian Academy of Sciences, ul. Vavilova 38, Moscow, 119991, Russia.
Biomed Opt Express. 2021 Apr 27;12(5):2938-2951. doi: 10.1364/BOE.420261. eCollection 2021 May 1.
The structures, sizes, and refractive indices (RI) of protein aggregates formed in a fibrinogen-thrombin system are examined using laser phase microscopy (LPM) accompanied by dynamic light scattering (DLS) and atomic force microscopy (AFM) measurements. Fibrin aggregates found in pure fibrinogen and fibrinogen with thrombin solutions by the DLS method, after drying the sample, form complex structures of different shapes and sizes on a glass surface. The LPM reveals submicron-sized dimeric structures in the pure fibrinogen solution, elongated micron-length structures, and rectangular structures in the fibrinogen-thrombin sample. AFM measurements show that the elongated structures form branched fibers, which in turn assembly into rectangular structures. All sizes obtained by LPM and AFM are consistent with DLS measurements. The refractive indices of all the structures, estimated by optical thickness, vary from 1.53 to 1.62, which indicates that they are fibrinogen derivatives. Effective visualization of the structure and determination of the optical properties for fibrin gel indicate that laser phase microscopy is capable of tissue imaging and characterization.
利用激光相显微镜（LPM），并结合动态光散射（DLS）和原子力显微镜（AFM）测量，研究了在纤维蛋白原 - 凝血酶系统中形成的蛋白质聚集体的结构、大小和折射率（RI）。通过DLS方法在纯纤维蛋白原和含有凝血酶的纤维蛋白原溶液中发现的纤维蛋白聚集体，在样品干燥后，在玻璃表面形成了不同形状和大小的复杂结构。LPM揭示了纯纤维蛋白原溶液中的亚微米级二聚体结构、纤维蛋白原 - 凝血酶样品中的微米级细长结构和矩形结构。AFM测量表明，细长结构形成分支纤维，这些分支纤维又组装成矩形结构。通过LPM和AFM获得的所有尺寸与DLS测量结果一致。通过光学厚度估计的所有结构的折射率在1.53至1.62之间变化，这表明它们是纤维蛋白原衍生物。对纤维蛋白凝胶结构的有效可视化和光学性质的测定表明，激光相显微镜能够进行组织成像和表征。
