TWO PHOTON LASER SCANNING FLUORESCENCE CORRELATION SPECTROSCOPY

双光子激光扫描荧光相关光谱

• 批准号: 6349422
• 负责人: DANIEL LARSON
• 金额: $ 3.56万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6349422
• 关键词: bioengineering /biomedical engineering; biomedical equipment development; biomedical resource; genetics; genome; lasers; technology /technique

Confocal imaging and fluorescence correlation spectroscopy (FCS) was applied towards characterization of lipid phase behavior and diffusion measurements in model lipid membranes. Giant unilamellar vesicles (GUVs) of defined lipid composition were first imaged by confocal fluorescence microscopy. Phase separation was visualized by partitioning of fluorescent lipid analogs with different fatty acid chain lengths into the coexisting phases. Cholesterol induces a marked change in the shapes of the phase domains for the binary mixture of DLPC1/DPPC. Characterization of the dynamics by measuring diffusion coefficients by FCS was carried out in liquid disordered (L__, liquid ordered (Lo) and gel phase (L__. The two-phase region for the binary mixture DLPC/DPPC (L_/L_) was identified by dual mode dynamics recognized in the shapes of the FCS autocorrelation curves. For binary mixtures of DLPC/cholesterol and DMPC/cholesterol, a continuous gradual transition of diffusion coefficients from high values (3.9 x 10-8 cm2/s) in the pure phospholipid down to tenfold slower diffusion as cholesterol was increased up to the phase boundary at 67 mol%.

共聚焦成像和荧光相关光谱（FCS） 用于表征脂质相行为和 模型脂质膜中的扩散测量。 巨型Unilamellar 首先对定义的脂质成分的囊泡（GUV）进行成像 共聚焦荧光显微镜。 相位分离被可视化 用不同脂肪酸的荧光脂质类似物的分配 链长到共存的阶段。 胆固醇诱导a 二进制相位域的形状的明显变化 DLPC1/DPPC的混合物。 通过测量动力学表征 通过FCS进行扩散系数 （L__，液体排序（LO）和凝胶相（L__。两相区域 对于二进制混合物DLPC/DPPC（L_/L_），通过二模式识别 在FCS自相关曲线的形状中识别的动力学。 对于DLPC/胆固醇和DMPC/胆固醇的二进制混合物， 从高的扩散系数的连续逐渐过渡 纯磷脂中的值（3.9 x 10-8 cm2/s）降至十倍 扩散较慢，因为胆固醇增加到相边界 在67 mol％。