OPTICAL MEASUREMENTS OF PH USING FLUORESCENCE LIFETIMES AND PHASE-MODULATION FLUOROMETRY
OPTICAL MEASUREMENTS OF PH USING FLUORESCENCE LIFETIMES AND PHASE-MODULATION FLUOROMETRY
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DOI：
10.1021/ac00061a007
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发表时间：
1993-07-01
影响因子：
7.4
通讯作者：
LAKOWICZ, JR
中科院分区：
文献类型：
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作者：
SZMACINSKI, H;LAKOWICZ, JR
我们使用相位调制荧光法测量了半萘荧光素（SNAFL）、半萘荧光素（SNARF）和BCECF的pH依赖性荧光衰减时间。的相位和调制值被发现是强烈的pH值依赖于在生理pH范围内，在容易获得的范围内的光调制频率从10到300 MHz，使这些探针作为基于寿命的pH传感器有用。相位和调制值取决于激发和发射波长以及pH。这种依赖性允许通过选择波长来选择pH灵敏度的范围，并通过使用几个波长的相位和/或调制测量来提高pH测量的精度。这些探针可以使用波长为543 nm的绿色He-Ne激光激发，这使得它们可以用于低成本的仪器中。相位和调制测量特别适用于传感应用，因为它们对由光漂白、探针冲刷和/或光损失引起的信号强度变化不敏感。
We measured the pH-dependent fluorescence decay times of the seminaphthofluoresceins (SNAFL), seminaphthorhodafluors (SNARF), and BCECF using phase-modulation fluorometry. The phase and modulation values were found to be strongly pH-dependent in the physiological pH range, over the easily accessible range of light modulation frequencies from 10 to 300 MHz, making these probes useful as lifetime-based pH sensors. The phase and modulation values are dependent on excitation and emission wavelength as well as pH. This dependence allows the range of pH sensitivity to be chosen by selection of the wavelength(s) and enables increased precision of the pH measurements by use of phase and/or modulation measurements at several wavelengths. These probes can be excited using a a green He-Ne laser at 543 nm, which allows their use in low cost instrumentation. Phase and modulation measurements are especially suitable for sensing applications because they are insensitive to the changes in signal intensity that result from photobleaching, probe washout, and/or light losses.