The spectral and kinetic characteristics of the fluorescence of the solutions of bovine serum albumin (BSA) and the dyes (N-(p-carboxyphenyl) imide of 4-(dimethylamino) naphthalic acid (CAPIDAN) and Bengal Rose (BR)) in BSA solutions were studied at 3.5 < pH < 8.0. It was discovered that the attenuation of CAPIDAN fluorescence at the studied pH region is described by the sum of three components (with the values of time constants: 6.0 ns < τ ₁ < 8.5 ns, 1.8 ns < τ ₂ < 2.2 ns, 0.4 ns < τ ₃ < 0.6 ns), while it is described by two components for BR (0.33 ns < τ ₁ < 0.4 ns, 2.0 ns < τ ₂ < 3.1 ns). It is shown that the mechanisms of the binding of dye and protein molecules are different for CAPIDAN and BR. The binding process of CAPIDAN and BSA is regulated by the conformation of the binding center. The interaction between the BR and BSA molecules is electrostatic, the magnitude of this interaction is determined by the ratio of the charges of the dye and protein molecules. The dependence of the wavelength of the maximum of the spectra, the intensity of the glow and the efficiency of quenching of the fluorescence of the molecules of the studied dyes on the pH is analyzed. The parameters dμ, which characterizes the change in the dipole moment of the fluorophore during its excitation, and η, which characterizes the change in the intensity at the maximum of the fluorescence spectrum at different pH solutions, were also determined for BR. The following ratios were determined at the studied pH range: and η < 1. The changes of the characteristics of the stationary fluorescence of the studied dyes at different pH of BSA solutions confirm the mechanisms of the binding between CAPIDAN or BR molecules and protein molecules.

牛血清白蛋白 (BSA) 和染料（4-（二甲氨基）萘甲酸的 N-（对羧基苯基）酰亚胺（CAPIDAN）和孟加拉玫瑰（BR））在 BSA 中的荧光光谱和动力学特征在 3.5 < pH < 8.0 下研究溶液。发现在研究的 pH 值区域 CAPIDAN 荧光的衰减由三个分量的总和来描述（时间常数的值：6.0 ns < τ ₁ < 8.5 ns, 1.8 ns < τ ₂ < 2.2 ns, 0.4 ns < τ ₃ < 0.6 ns)，而它由 BR 的两个分量描述 (0.33 ns < τ ₁ < 0.4 ns, 2.0 ns < τ ₂< 3.1 纳秒）。结果表明，CAPIDAN和BR的染料和蛋白质分子结合的机制不同。CAPIDAN与BSA的结合过程受结合中心构象的调控。BR 和 BSA 分子之间的相互作用是静电的，这种相互作用的大小由染料和蛋白质分子的电荷比决定。分析了光谱最大值的波长、发光强度和所研究染料分子的荧光猝灭效率对 pH 值的依赖性。参数 d μ表征荧光团在激发期间偶极矩的变化，以及η，它表征了不同 pH 溶液下荧光光谱最大值处的强度变化，也用于 BR。在所研究的 pH 范围内确定了以下比率：和η < 1。所研究的染料在 BSA 溶液不同 pH 值下的固定荧光特性的变化证实了 CAPIDAN 或 BR 分子与蛋白质分子之间的结合机制。