Hong F T, Mauzerall D
Proc Natl Acad Sci U S A. 1974 Apr;71(4):1564-8. doi: 10.1073/pnas.71.4.1564.
The electrical response of a pigmented lipid bilayer to a short laser pulse is measured by a tunable voltage clamp method. In this method, a variable access impedance permits "tuning" of the observed relaxations for optimal measurements. Analysis of the data so obtained leads to an equivalent circuit that contains a novel chemical capacitance charged by the specific photoreaction across a single membrane-water interface. This chemical capacitance is distinct from the ordinary membrane capacitance. The intrinsic chemical rate constant obtained from the equivalent circuit analysis is shown to be the pseudo-first-order rate constant of the reverse dark reaction of the reduced acceptor and the oxidized pigment. The tunable voltage clamp method of measurement and analysis allows unambiguous separation of this rate constant into resistive and capacitative elements, which are interpreted in molecular terms.
通过可调电压钳位法测量色素脂质双层对短激光脉冲的电响应。在这种方法中，可变接入阻抗允许对观察到的弛豫进行“调谐”以实现最佳测量。对如此获得的数据进行分析得出一个等效电路，该等效电路包含一个由跨单个膜 - 水界面的特定光反应充电的新型化学电容。这种化学电容与普通膜电容不同。从等效电路分析中获得的本征化学速率常数显示为还原受体和氧化色素的反向暗反应的伪一级速率常数。测量和分析的可调电压钳位法允许将该速率常数明确分离为电阻性和电容性元件，并从分子角度进行解释。
