E MAIL CONSULTATIONS

第26届美国光生物学会年会 内源性和给药荧光团的非线性激发 提供衍射受限的三维成像I单元， 活组织制备。 多光子的主要优点 定量成像的激励是（1）固有的定位 的兴奋到一个小的明确界定的体积在一个高的焦点 数值孔径物镜，以及（2）激发 具有更好穿透性的紫外和蓝色光学转变 近红外照明 这些优点可以实现高分辨率 包括光敏化合物的荧光分子的成像 例如Photofrin，在真实的肿瘤环境中。 Photofrin 观察到激发从单光子过程变为双光子过程， 其范围为700-740 nm，并可在750-900 nm范围内被双光子激发 nm. 其特征在于荧光截面为 在整个该范围内大约0.5 × 10-50 cm 4 s/光子。 以来 来源于NADH的线粒体自发荧光也经历 在该波长范围内的双光子激发下，两种物质都可以被 同时拍摄。 我们观察到Photofrin最初定位于 质膜，然后是亚细胞定位， 线粒体和其他细胞器。 即使经过长时间的 孵育，药物存在于构成肿瘤的细胞之间 球状体 药物孵育导致方案依赖性降低， 自发荧光 最后，观察到光动力作用， 显著改变细胞自发荧光的几个方面， 以及细胞形态。 DRBIO由NIH RR 04224支持。 M.G. N 是由NRSA 1 F32 CA 72225-02支持的NIH博士后研究员。

26th annual meeting of the American Society for Photobiology Non-linear excitation of endogenous and administered fluorophores provides diffraction limited three-dimensional imaging I cells and living tissue preparations. The chief advantages of multiphoton excitation for quantitative imaging are (1) the inherent localization of excitation to a small well-defined volume at the focus of a high numerical aperture objective, and (2) the ability to excite ultraviolet and blue optical transitions with better penetrating near-infrared illumination. The advantages enable high-resolution imaging of fluorescent molecules, including photosensitizing compounds such as Photofrin, within realistic tumor environments. Photofrin excitation is observed to change from a one to two-photon process in the range from 700-740 nm and can be two-photon excited from 750-900 nm. It is characterized by a fluorescence cross section of approximately 0.5 x 10-50 cm4 s/photon throughout this range. Since mitochondrial autofluorescence originating from NADH also undergoes two-photon excitation in this wavelength range, both species can be simultaneously imaged. We observe Photofrin to localize initially to the plasma membrane followed by subcellular localization in mitochondria and possibly other organelles. Even after prolonged incubation, drug is present between cells comprising the tumor spheroids. Drug incubation results in protocol dependent decreases in autofluorescence. Finally, photodynamic action is observed to dramatically alter several aspects of cellular autofluorescence, as well as cell morphology. Supported at DRBIO by NIH RR04224. M.G.N. is a NIH postdoctoral fellow supported by NRSA 1 F32 CA 72225-02.