异硫氰酸荧光素-葡聚糖

一般描述

葡聚糖是葡萄糖酐聚合物。由大约95%的α-D-(166)键组成。剩余的（163）键作为葡聚糖的分支。 天然葡聚糖的分子量(MW)经证实在 900 万至 5 亿的范围内。FITC-葡聚糖的最大激发波长为 490nm。它的 pH 范围为 5 至 9。

应用

用异硫氰酸荧光素标记的葡聚糖可用于动物的灌注研究。 异硫氰酸荧光素-葡聚糖（FITC-右旋糖酐，荧光素右旋糖酐，FITC）用于以下过程： 荧光素-葡聚糖显微镜。 评估多形核白细胞α防御素表达转基因小鼠体内肺血管的通透性。 通过流式细胞术定量细胞吞噬能力。 标记α乳白蛋白和脱氧核糖核酸酶。 FITC-葡聚糖广泛用于运用显微荧光法进行微循环和细胞通透性研究。它还适用于植物细胞壁孔隙度和毛细血管通透性研究。

其他说明

天然葡聚糖的分子量(MW)经证实在 900 万至 5 亿的范围内。较低分子量的葡聚糖将表现出略微较少的分支，并且具有更窄的分子量分布范围。分子量大于 10,000 的葡聚糖则表现为高度支化。 随着分子量增加，葡聚糖分子的对称性增强。 分子量为 2,000 至 10,000 的葡聚糖表现出可膨胀线圈的特性。 在分子量低于 2,000 时，葡聚糖更像棒状。通过以下一种或多种方法测量葡聚糖的分子量：低角度激光散射、尺寸排阻色谱法、铜络合和蒽酮试剂显色还原末端糖测定和粘度。

制备说明

通常以 25mg/ml 或更高的浓度测试 FITC 葡聚糖在水中的溶解度。 溶液应避光。 在体内，FITC-葡聚糖稳定超过 24 小时。

General Description

Dextran is a polymer of anhydroglucose. It is composed of approximately 95% α-D-(166) linkages. The remaining (163) linkages account for the branching of dextran. Native dextran has been found to have a molecular weight (MW) in the range of 9 million to 500 million. FITC-dextran has an excitation maximum of 490 nm. It has a pH range of 5 to 9.

Application

Fluorescein isothiocyanate–dextran (FITC-dextran, fluorescein-dextran, FITC) was used in the following processes: Fluorescein-dextran microscopy. To evaluate the in vivo pulmonary vascular permeability in polymorphonuclear leukocyte α-defensins expressing transgenic mice. To quantify endocytic activity by flow cytometry. To label α-lactalbumin and ribonuclease. FITC-dextran is suitable for extensive microcirculation and cell permeability research utilizing microfluorimetry. It is also suitable for the study of plant cell wall porosity and capillary permeability. Dextran labeled with fluorescein isothiocyanate for possible use in perfusion studies in animals.

Other Notes

Native dextran has been found to have a molecular weight (MW) in the range of 9 million to 500 million. Lower MW dextrans will exhibit slightly less branching and have a more narrow range of MW distribution. Dextrans with MW greater than 10,000 behave as if they are highly branched. As the MW increases, dextran molecules attain greater symmetry. Dextrans with MW of 2,000 to 10,000, exhibit the properties of an expandable coil. At MW below 2,000, dextran is more rod-like. The MW of dextran is measured by one or more of the following methods: low angle laser light scattering, size exclusion chromatography, copper-complexation and anthrone reagent colorometric reducing-end sugar determination and viscosity.