Orientationally enhanced photocurrent and electrooptic modulation effects in bacteriorhodopsin/polyvinyl alcohol thin films
Orientationally enhanced photocurrent and electrooptic modulation effects in bacteriorhodopsin/polyvinyl alcohol thin films
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细菌视紫红质/聚乙烯醇薄膜中的定向增强光电流和电光调制效应
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发表时间：
2002
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通讯作者：
K. Cooper
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作者：
Liangmin Zhang;T. Zeng;R. Claus;K. Cooper
细菌视紫红质的聚合物膜，通过将紫色膜片段嵌入到聚（乙烯醇）矩阵中而不进行场极化而形成，当在膜上施加AC调制矩形电压或正弦电压时，表现出调制的光电流和电光效应。当调制频率低于100 Hz时，两种效应均被紫膜碎片的取向所增强，并表现出两种不同的取向时间常数。在低频（~ 7.1 Hz）下的取向增强来自膜的永久偶极矩，而在高频（~ 74.8 Hz）下的取向增强则归因于紫膜分子的诱导偶极矩。为了定量分析这些过程，提出了一个理论模型。结合模型计算和拟合的实验结果，我们确定了膜材料的永久偶极矩为1.33kD，诱导偶极矩为1.10 -13 cm ~ 3。我们也是恶魔...
Polymeric films of bacteriorhodopsin, formed by embedding purple membrane fragments into a poly(vinyl alcohol) matrix without field poling, exhibit modulated photocurrent and electrooptic effects when an AC modulating rectangular voltage or a sinusoidal voltage is applied across the films. When the modulating frequencies are lower than 100 Hz, both effects are enhanced by the orientation of the purple membrane fragments and exhibit two different orientational time constants. The orientational enhancement at low frequencies (∼7.1 Hz) arises from the permanent dipole moments of membranes, and the enhancement at higher frequencies (∼74.8 Hz) is attributed to the induced dipole moments of the purple membrane molecules. For quantitative analyses of these processes, a theoretical model is proposed. From the combination of model calculations and fitted experimental results, we determine that the permanent dipole moment of the membrane material is ∼33 kD and the induced dipole moment is ∼10-13 cm3. We also demons...