Abstract Langmuir monolayers of globular proteins (bovine serum albumin, i.e., BSA and human serum albumin, i.e., HSA) are formed on the water surface at pH ≈ 7.0, and compact protein layers are deposited on hydrophilic Si (001) surface using the Langmuir-Blodgett deposition method. Stability of these protein monolayers are studied from the normalized molecular area-time (A/A0-t) curves, which confirms that deposition over a long period of time is possible from both the protein monolayers. Compact bimolecular layered structure of the protein films are deposited on Si surface at higher surface pressure (17 mN/m) of the BSA and HSA monolayers, which is confirmed from the electron density profiles (EDPs) obtained from the analysis of the X-ray reflectivity data. Mostly the thickness of the molecular layers increases as the molecular tilting takes place and new molecules are deposited inside the vacant positions of the layer and as a result the electrons per unit area increases. EDPs obtained from the deposited BSA and HSA films also confirm that the increment in molecular tilting and electrons per unit area is protein specific. EDPs and surface morphology obtained from the atomic force microscopy images of the deposited films confirm that interrupted layer-by-layer or Frank-van der Merwe growth mode is followed in such protein multilayer deposition.

中文翻译：

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亲水性硅 (001) 表面朗缪尔-布洛杰特沉积下的致密蛋白（牛血清白蛋白/人血清白蛋白）层

摘要 球状蛋白（牛血清白蛋白，即 BSA 和人血清白蛋白，即 HSA）的 Langmuir 单层在 pH ≈ 7.0 时形成于水表面，并使用 Langmuir 将致密的蛋白质层沉积在亲水性 Si（001）表面上。 -Blodgett 沉积法。从归一化的分子面积-时间 (A/A0-t) 曲线研究这些蛋白质单层的稳定性，这证实了两种蛋白质单层都可以长时间沉积。在 BSA 和 HSA 单层的较高表面压力 (17 mN/m) 下，蛋白质膜的紧凑双分子层状结构沉积在 Si 表面上，这从 X 射线分析获得的电子密度分布 (EDP) 中得到证实反射率数据。大多数情况下，分子层的厚度会随着分子倾斜的发生而增加，并且新分子沉积在层的空位内，结果每单位面积的电子增加。从沉积的 BSA 和 HSA 薄膜中获得的 EDP 也证实了分子倾斜和每单位面积电子的增量是蛋白质特异性的。从沉积膜的原子力显微镜图像获得的 EDP 和表面形态证实，在这种蛋白质多层沉积中遵循中断的逐层或 Frank-van der Merwe 生长模式。从沉积的 BSA 和 HSA 薄膜中获得的 EDP 也证实了分子倾斜和每单位面积电子的增量是蛋白质特异性的。从沉积膜的原子力显微镜图像获得的 EDP 和表面形态证实，在这种蛋白质多层沉积中遵循中断的逐层或 Frank-van der Merwe 生长模式。从沉积的 BSA 和 HSA 薄膜中获得的 EDP 也证实了分子倾斜和每单位面积电子的增量是蛋白质特异性的。从沉积膜的原子力显微镜图像获得的 EDP 和表面形态证实，在这种蛋白质多层沉积中遵循中断的逐层或 Frank-van der Merwe 生长模式。