School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama City, Kanagawa 223-8522, Japan.
Photodiagnosis Photodyn Ther. 2014 Dec;11(4):586-94. doi: 10.1016/j.pdpdt.2014.09.001. Epub 2014 Sep 16.
The purpose of this study is to establish a sensing system to estimate relative talaporfin sodium concentration in skin to evaluate the risk of skin photosensitivity after photodynamic therapy (PDT) using percutaneous fluorescence spectroscopy. A prototype fluorescence sensing probe was made using a pair of 5-cm-long diffuse tips of plastic optical fibers for excitation light irradiation and fluorescence collection. Talaporfin sodium (2.5mg/kg) was intravenously administrated to three pigs, and the talaporfin sodium concentration in plasma was measured. The fluorescence sensing probe was attached to the skin and excited by a LED light with a peak wavelength of 409 ± 16 nm to obtain the mean area of the talaporfin sodium fluorescence spectral peak (Sfluo). The time history of the talaporfin sodium concentration in tissue was estimated using a two-compartment pharmacokinetic model. The time history of Sfluo was described as a composite function of the time history of the measured talaporfin sodium concentration in plasma and that of the estimated concentration in tissue as a double exponential decay function. The relative talaporfin sodium concentration in tissue and the relative contributions of fluorescence from tissue and plasma to Sfluo were estimated by the fluorescence system with the numerical pharmacokinetic model. Results also show that tissue compression equivalent to venous pressure might be effective to suppress the contribution of talaporfin sodium fluorescence in plasma.
本研究旨在建立一种传感系统，通过经皮荧光光谱法来评估光动力疗法（PDT）后皮肤光敏性的风险，从而估算皮肤中相对的替拉扎明钠浓度。使用一对 5cm 长的漫射塑料光纤尖端作为激发光照射和荧光收集，制作了原型荧光传感探头。向三头猪静脉内给予替拉扎明钠（2.5mg/kg），并测量血浆中的替拉扎明钠浓度。将荧光传感探头附着于皮肤，并使用峰值波长为 409±16nm 的 LED 光激发，以获得替拉扎明钠荧光光谱峰的平均面积（Sfluo）。使用两室药代动力学模型估算组织中替拉扎明钠浓度的时间历程。Sfluo 的时间历程被描述为血浆中替拉扎明钠实测浓度的时间历程和组织中替拉扎明钠浓度的时间历程的复合函数，作为双指数衰减函数。通过带有数值药代动力学模型的荧光系统，估算了组织中的相对替拉扎明钠浓度以及组织和血浆对 Sfluo 的荧光贡献的相对贡献。结果还表明，组织压迫等效于静脉压可能有效抑制血浆中替拉扎明钠荧光的贡献。
