Lurie D J, Smith F A, Shukri A
Int J Appl Radiat Isot. 1985 Jan;36(1):57-62. doi: 10.1016/0020-708x(85)90055-9.
The interaction of [111In]Tris-chelates with protein molecules in aqueous solution at room temperature has been studied using time-integral and time-differential PAC. Increasing amounts of apo-transferrin were added to solutions of [111In]tropolonate, -acetylacetonate, -oxinate and -oxine sulphate, and of haemoglobin to [111In]tropolonate. The transfer of 111In from chelate to protein was monitored by time-integral PAC measurements. Analysis of these data in erms of stability constants showed that with added transferrin complete dissociation of each 111In chelate occurred with increasing protein concentration, the radiolabel being sequestered by the protein molecules. Confirmation of this was provided by time-differential PAC measurements at four tropolone:transferrin relative concentrations, and in the pure systems. A value for the first stability constant of transferrin is presented. Analysis of time-integral PAC data showed that added haemoglobin did not cause complete dissociation of [111In]tropolonate, a [111In]tropolone-haemoglobin complex being formed. Time-differential PAC studies of the [111In]tropolonate:haemoglobin and [111In]haemoglobin systems at 77 K and 295 K supported this conclusion, revealing quadrupole frequencies of 14.0 +/- 0.6 MHz in [111In]haemoglobin and 9.1 +/- 1.1 MHz in the mixed system.
利用时间积分和时间微分扰动角关联（PAC）技术，研究了室温下水溶液中[111In]三齿螯合物与蛋白质分子之间的相互作用。向[111In]托酚酮、[111In]乙酰丙酮、[111In]8-羟基喹啉和[111In]硫酸8-羟基喹啉溶液中加入越来越多的脱铁转铁蛋白，向[111In]托酚酮溶液中加入血红蛋白。通过时间积分PAC测量监测111In从螯合物向蛋白质的转移。根据稳定常数对这些数据进行分析表明，随着蛋白质浓度的增加，加入转铁蛋白后每种111In螯合物都会完全解离，放射性标记被蛋白质分子螯合。在四个托酚酮与转铁蛋白相对浓度下以及在纯体系中进行的时间微分PAC测量证实了这一点。给出了转铁蛋白的一级稳定常数的值。时间积分PAC数据分析表明，加入血红蛋白不会导致[111In]托酚酮完全解离，而是形成了[111In]托酚酮-血红蛋白复合物。在77K和295K下对[111In]托酚酮：血红蛋白和[111In]血红蛋白体系进行的时间微分PAC研究支持了这一结论，揭示了[111In]血红蛋白中的四极频率为14.0±0.6MHz，混合体系中的四极频率为9.1±1.1MHz。
