PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 24 rue Lhomond, 75005, Paris, France.
Sorbonne Université, Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Théorique de la Matière Condensée (LPTMC), 4 place Jussieu, case courrier 121, 75252, Paris Cedex 05, France.
Anal Chim Acta. 2022 Sep 8;1225:340180. doi: 10.1016/j.aca.2022.340180. Epub 2022 Aug 3.
Titration without separation, e.g. quantification of a target species in living cells, is a challenge of analytical chemistry. We perform the selective detection of a target using the kinetics involved in a photochemical process and develop a correlation method that we illustrate by the titration of a fluorescent photoswitcher and the target of a photoswitching sensor. Correlating an input time series and a well-chosen weighting function associated with a variable characteristic time yields a spectrum of characteristic times. The upper integration limit of the correlation output can be chosen to match the argument of an extremum of the spectrum with a characteristic time of the input time series in order to quantify the target. A similar procedure is followed to optimize the signal-to-noise ratio. Selectivity and signal-to-noise ratio associated with 15 weighting functions are theoretically predicted. The results are applied to the titration of the reversibly photoswitchable fluorescent protein Dronpa-2 and the titration of calcium using a reversibly photoswitchable fluorescent sensor. The performance of the correlation method is favorably compared to the one of other dynamic contrast protocols.
无需分离的滴定，例如活细胞中目标物种的定量，是分析化学的一个挑战。我们使用光化学过程中涉及的动力学来进行目标的选择性检测，并开发了一种相关方法，我们通过荧光光开关和光开关传感器的目标的滴定来举例说明。将输入时间序列与与变量特征时间相关联的适当加权函数相关联，可得到特征时间谱。相关输出的上积分限可以选择与输入时间序列的特征时间的极值的参数匹配，以便定量目标。类似的过程用于优化信噪比。理论上预测了与 15 个加权函数相关的选择性和信噪比。结果应用于可逆光开关荧光蛋白 Dronpa-2 的滴定以及使用可逆光开关荧光传感器的钙滴定。相关方法的性能与其他动态对比协议的性能相比具有优势。
