Cy5.5 是一种 CY 染料。CY 为花菁 (Cyanine) 的缩写，是由奇数个甲基单位连接的两个氮原子组成的化合物。菁类化合物具有波长长、吸收和发射可调、消光系数高、水溶性好、合成相对简单等特点。CY 系类染料常被用于蛋白，抗体以及小分子化合物的标记，对于蛋白抗体的标记，可以通过简单的混合反应来完成结合，以下我们介绍了蛋白抗体标记的标记方法，具有一定的参考意义。

Cy5.5 is a CY dye. CY, short for Cyanine, is a compound consisting of two nitrogen atoms connected by an odd number of methyl units. Cyanine compounds have the characteristics of long wavelength, adjustable absorption and emission, high extinction coefficient, good water solubility and relatively simple synthesis. CY dyes are of en used for the labeling of proteins, antibodies and small molecular compounds. For the labeling of protein antibodies, the combination can be completed through a simple mixing reaction. Below, we introduce the labeling method of protein antibody labeling, which has certain reference significance.

Solid

原液制备
1. 蛋白准备
为了获得最佳标记效果，请将蛋白 (抗体) 浓度配制为 2 mg/mL。
1) 蛋白溶液 pH 值应为 8.5±0.5，若 pH 低于 8.0，则用 1 M 碳酸氢钠进行调整。
2) 若蛋白浓度低于 2 mg/mL，标记效率会大大降低，为了获得最佳标记效率，建议最终蛋白质浓度范围为 2-10 mg/mL。
3) 蛋白必须在不含伯胺 (如 Tris 或甘氨酸) 和铵离子的缓冲液中，否则会影响标记效率。
2. 染料准备
将无水 DMSO 稀释 CY 染料，制成 10 mM 储备溶液。通过玻璃管或旋涡充分混合。
注：CY 储存液建议分装后于 -20 ℃ 或 -80 ℃ 避光保存。
3. 染料工作液用量计算
标记反应所需的 CY 染料用量取决于要标记蛋白的用量，CY 染料与蛋白的最佳摩尔比为 10 左右。
例：假如所需标记蛋白为 500 μL 2 mg/mL 的 IgG (MW=150,000),用 100 μL DMSO 溶解一管 1 mg CY 染料，则所需 CY 体积为 3.95 μL，详细计算流程如下 (以 CY3-NHS ester 为例) ：
1) mmol (IgG) = mg/mL (IgG) ×mL (IgG) / MW (IgG) =2 mg/mL×0.5 mL / 150,000 mg/mmol= 6.7×10-6 mmol
2) mmol (CY3-NHS ester) = mmol (IgG) ×10 =6.7×10-6 mmol×10 = 6.7×10-5 mmol
3) μL (CY3-NHS ester) = mmol (CY3-NHS ester) ×MW (CY3-NHS ester) / mg/μL (CY3-NHS ester) = 6.7×10-5 mmol× 590.15 mg/mmol / 0.01 mg/μL =3.95 μL (CY3-NHS ester)


使用方法
1. 标记反应
1) 取算好体积的新鲜配制的

Cy5.5-labeled factor VIIa is developed for imagining cancer. Cy5.5 labeled with these targeting proteins specifically localize to the tumor xenografts for at least 14 days but unconjugated Cy5.5 does not localize to any xenografts or organs. This method of imaging anti-tissue factor in the tumor VECs may be useful in detecting primary tumors and metastases as well as monitoring in vivo therapeutic responses. pH/temperature sensitive magnetic nanogels conjugated with Cy5.5-labled lactoferrin (Cy5.5-Lf-MPNA nanogels) are developed as a promising contrast agent for preoperative MRI and intraoperative fluorescence imaging of glioma. has not independently confirmed the accuracy of these methods. They are for reference only.

Room temperature in continental US; may vary elsewhere.

Powder -20°C 3 years；4°C 2 years

[1]. Ptaszek M. Rational design of fluorophores for in vivo applications. Prog Mol Biol Transl Sci. 2013;113:59-108.
[2]. Zhu S, et al. Visualizing cancer and response to therapy in vivo using Cy5.5-labeled factor VIIa and anti-tissue factor antibody. J Drug Target. 2015 Apr;23(3):257-65.
[3]. Shindy, H. A. (2017).

In Vitro: DMSO : 100 mg/mL (109.05 mM; Need ultrasonic)H₂O : 5 mg/mL (5.45 mM; ultrasonic and warming and heat to 60°C)配制储备液