Kovács I, Váró G
Central Research Institute for Physics, Hungarian Academy of Sciences, Budapest.
Acta Biochim Biophys Hung. 1988;23(3-4):265-70.
Dielectric dispersion effects were studied in purple membranes of different hydration levels. The capacitance and conductivity were measured over the frequency range of 10(2) Hz to 10(5) Hz. With increase in the hydration level, the conductivity increases sharply above the critical hydration of hc = 0.06 g H2O/g protein. This critical hydration is close to the extent of the first continuous strongly bound water layer and is interpreted as the threshold for percolative proton transfer. The capacitance increases continuously with increasing hydration and a larger increase above the water content of 0.1 g H2O/g protein can be seen only at low frequencies. Maxwell-Wagner relaxation also appears above this hydration, showing the presence of a bulk water phase.
研究了不同水化水平的紫膜中的介电色散效应。在10²Hz至10⁵Hz的频率范围内测量了电容和电导率。随着水化水平的增加，在临界水化hc = 0.06 g H₂O/g蛋白质以上，电导率急剧增加。这种临界水化接近第一个连续强结合水层的范围，并被解释为渗流质子转移的阈值。电容随着水化的增加而持续增加，并且仅在低频下，在水含量高于0.1 g H₂O/g蛋白质时才会出现更大的增加。麦克斯韦-瓦格纳弛豫也出现在这个水化水平以上，表明存在大量水相。
