牛血清白蛋白（Bovine Serum Albumin，BSA），也称为第五组分（Cohn Fraction V），CAS NO. 9048-46-8，具有非常广泛的生物学和诊断学研究用途。免疫实验中可用作封闭剂，功能类似脱脂奶粉，动物正常血清。也可用作载体蛋白，将其交联于半抗原和其他弱抗原上，以提高抗体生产的免疫原性。酶和重组蛋白生产制品中加入BSA，不仅可以提高稳定性，延长保存周期；还能防止制品黏附到管壁或其他材料表面造成的损失。也常用于生物制药的加工过程，或者作为营养成分加入细胞和微生物培养体系中。还能用作蛋白定量检测所需的定量标准品。

本品为阳离子化牛血清白蛋白（Cationic Bovine Serum Albumin, cBSA），经特殊的化学处理蛋白包含更多的胺基，使其在中性pH下有更多正电荷。cBSA是一种优越的载体蛋白用来生产抗体，因其比未修饰BSA偶联物具更强的免疫反应性。cBSA还能用作免疫原来诱导免疫复合物引起的肾小球肾炎（ICGN）小鼠模型。本品以液体形式提供，浓度为2mg/ml。

保存与运输方法

保存：-20℃避光保存，1年有效。

运输：干冰运输。

注意事项

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参考文献

1、Bass PS, Drake AF, Wang Y, Thomas JH, Davies DR. Cationization of bovine serum albumin alters its conformation as well as its charge. Lab Invest. 1990 Feb;62(2):185-8. PMID: 2304331.

2、Debiec H, Lefeu F, Kemper MJ, Niaudet P, Deschênes G, Remuzzi G, Ulinski T, Ronco P. Early-childhood membranous nephropathy due to cationic bovine serum albumin. N Engl J Med. 2011 Jun 2;364(22):2101-10. PMID: 21631322.

3、Jin-Shuen Chen, Ann Chen, Li-Chien Chang, Wun-Shaing Wayne Chang, Herng-Sheng Lee, Shih-Hua Lin, Yuh-Feng Lin, Mouse model of membranous nephropathy induced by cationic bovine serum albumin: antigen dose–response relations and strain differences, Nephrology Dialysis Transplantation, Volume 19, Issue 11, November 2004, Pages 2721–2728.

4、Wu CC, Chen JS, Chen SJ, Lin SH, Chen A, Chang LC, Sytwu HK, Lin YF. Kinetics of adaptive immunity to cationic bovine serum albumin-induced membranous nephropathy. Kidney Int. 2007 Oct;72(7):831-40. doi: 10.1038/sj.ki.5002426. Epub 2007 Jul 11. PMID: 17622271.

以下来源于文献资料（cBSA的制备方法，Ref, Mouse model of membranous nephropathy induced by cationic bovine serum albumin: antigen dose–response relations and strain differences）

Briefly, 200 g of crystallized bovine serum albumin was dissolved in 1.2 ml of distilled water. Anhydrous ethylenediamine (EDA) was prepared by mixing 2.68 ml of EDA and 20 ml of distilled water. The pH was adjusted to 4.75 with 6 N HCl and the solution cooled to 25°C. This EDA solution was added slowly to the BSA solution followed by 150 mg of 1-ethyl-3-[(3-dimethylaminopropyl)-carbodiimide hydrochloride] (EDC) with continuous stirring for 4 h. The product was purified using the pH-dependent binding technique. The reaction solution was applied to a 1 ml Econo Pac® High S cationic ion-exchange column (BioRad, Hercules, CA). After binding of BSA to the ion-exchange beads, the column was washed with 10 ml of pH 6.8 phosphate buffer (40 mM) to remove the non-reacted BSA. Subsequently, the modified BSA was eluted with 5 ml of 40 mM phosphate buffer (pH 10.6). All collections were then pooled, concentrated, and reconstituted with saline. Prior to use, the final protein concentration was measured using UV absorbance at 280 nm.