FITC-Dextran (MW 4000) (solution) 

FITC-Dextran (MW 4000) (solution) is a fluorescent probe for fluorescein isothiocyanate (FITC) dextran (Ex=495 nm; Em=525 nm). FITC-Dextran (MW 4000) can be used as a marker to reveal heat shock-induced cell damage and to study the early and late stages of apoptosis. FITC-Dextran (MW 4000) can also be used for cell permeability studies, such as blood-brain barrier permeability and determination of the extent of blood-brain barrier disruption^[1][2][3].
Solvent and Concentration: Sterile water: 2 mM

指南 (以下是我们推荐的方案。此方案仅供参考，请根据您的具体需求进行修改)。

1. 溶液配置^[2]
1.1 工作液的配制
用 PBS 或无血清细胞培养基稀释至 0.1 mg/mL (根据实验优化)。
注意：工作液现配现用，避光。
母液分装后 -20°C 或 -80°C 避光保存，避免反复冻融。
注意：0.22 μm 滤膜过滤除菌。

2. 细胞染色
适用于正在发生凋亡的 HeLa 细胞和人外周血单个核细胞 (PBMC) (活的 HeLa 和 PBMC 不被 FITC-Dextran 染色)。
2.1 43.5°C 孵育 1 h，37°C 孵育 8 h，诱导细胞凋亡。
2.2 将细胞悬浮在 100 μL 的培养基中，在 Q-prep 管与 10 μL 的 propidium iodide (PI) ，10 μL 的 FITC-Dextran (MW 4000) 混合，PI 和 FITC-Dextran (MW 4000) 的最终浓度分别为 7.5 μM 和 1.13 μM。
2. 3 将细胞在室温黑暗条件下培养 25 分钟。
2. 4 取 3 mL 培养基的标记细胞，500 g 离心 10 分钟。
2.5 取离心细胞，加入 1 mL 培养基，用流式细胞术或荧光显微镜分析 (PI: Ex=500 nm, Em=600 nm; FITC-Dextran (MW 4000) : Ex=495 nm, Em=525 nm)。


细胞旁渗透性检测^[4]
1. 在 transwell 室的基础培养基中加入 FITC-Dextran (0.1 mg/mL)。
2. 在 15 分钟后从 transwell 插入器中收集培养基。
3. 测量荧光信号 (Ex=485 nm, Em=538 nm)。
4. 根据荧光强度计算 FITC-Dextran 浓度。
5. 计算渗透率。

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

指南 (以下是我们推荐的方案。此方案仅供参考，请根据您的具体需求进行修改)。

肠屏障功能测定^[5]
1. 小鼠饥饿处理 4 小时。
2. FITC-Dextran MW 4000 灌胃小鼠 (0.6 mg/g)。
3. 在 4 h 内测量荧光强度 (Ex nm/Em 520 nm)。

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

60842-46-8

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Okabayashi K, et al. Cdc42 activates paracellular transport in polarised submandibular gland cells. Arch Oral Biol. 2021 Dec;132:105276.  [Content Brief]

  [2]. Yu W, et al. ACE2 contributes to the maintenance of mouse epithelial barrier function. Biochem Biophys Res Commun. 2020 Dec 17;533(4):1276-1282.  [Content Brief]

  [3]. Moumaris M, et al. Fluorescein isothiocyanate-dextran can track apoptosis and necrosis induced by heat shock of peripheral blood mononuclear cells and HeLa cells[J]. Open Biological Sciences Journal, 2015, 1(1).

  [4]. Natarajan R, et al. Fluorescein Isothiocyanate (FITC)-Dextran Extravasation as a Measure of Blood-Brain Barrier Permeability. Curr Protoc Neurosci. 2017 Apr 10;79:9.58.1-9.58.15.  [Content Brief]

  [5]. Eriksson I, et al. Analysis of Lysosomal pH by Flow Cytometry Using FITC-Dextran Loaded Cells. Methods Mol Biol. 2017;1594:179-189.  [Content Brief]