In vivo spectroscopic properties of the fluorescent pH indicator biscarboxyethyl carboxyfluorescein.
In vivo spectroscopic properties of the fluorescent pH indicator biscarboxyethyl carboxyfluorescein.
复制标题
荧光 pH 指示剂双羧乙基羧基荧光素的体内光谱特性。
DOI：
10.1016/1011-1344(95)90243-0
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Valenzeno,DP
中科院分区：
文献类型：
--
作者：
Russell,DA;Pottier,RH;Valenzeno,DP
从注射的pH敏感的探针biscarboxyethylcarboxyfluorescein（BCECF）的荧光经皮检测已被用于监测清醒动物的血浆pH值。荧光信号必须参照标准曲线进行校准。该标准校准曲线已使用体外方法获得。在这里，它表明，温度影响体外校准曲线测定，因此影响经皮测量确定的pH值。已获得两条校准曲线，一条在室温（约25°C）下，另一条在37°C下。在pH 7.01时，校准曲线相交，因此，在碱性更强的pH值下，使用室温校准数据将导致高估血浆pH值。低于pH 7.01时，血浆pH值将被低估。显示了从注射BCECF的小鼠记录的经皮荧光光谱，表明使用室温校准估计基线血浆pH值过高约0.3 pH单位，并且当允许动物呼吸含有15%CO2的气氛时，酸化的程度被高估了0.7 pH单位。此外，它表明，在体外牛血清白蛋白的浓度与白蛋白浓度在体内转移的吸收，荧光激发和发射光谱的BCECF。然而，在体内记录的荧光光谱显示没有这样的位移。结果表明，经皮荧光测量在体内的体外校准可能会产生误导，在pH值测量的情况下，不注意温度可能会导致虚假的结果。
Transcutaneous detection of fluorescence from an injection of the pH-sensitive probe biscarboxyethyl carboxyfluorescein (BCECF) has been used to monitor plasma pH in conscious animals. The fluorescence signal must be calibrated with reference to a standard curve. This standardm calibration curve has been achieved using in vitro methods. Here it is shown that temperature influences the calibration curve determination in vitro and hence influences the pH determined from transcutaneous measurements. Two calibration curves have been obtained, one at room temperature (approximately 25°C) and the other at 37°C. At pH 7.01 the calibration curves intersect, so that, at more alkaline pH values, use of room temperature calibration data will lead to an overestimate of plasma pH. Below pH 7.01, plasma pH will be underestimated. Transcutaneous fluorescence spectra recorded from a mouse injected with BCECF are shown, indicating that baseline plasma pH was estimated about 0.3 pH units too high using room temperature calibration, and that the extent of acidification when the animal was allowed to breathe an atmosphere containing 15% CO2was overestimated by 0.7 pH units. Additionally, it is shown that in vitro bovine serum albumin at concentrations comparable with albumin concentrations in vivo shifts the absorption, fluorescence excitation and emission spectra of BCECF. However, fluorescence spectra recorded in vivo show no such shift. The results indicate that in vitro calibration for transcutaneous fluoresence measurements in vivo can be misleading, and that in the case of pH measurement inattention to temperature can lead to spurious results.