
Solubility in DMSO/PBS | X-Gal should be dissolved in DMSO and then diluted with PBS(PBS 7.2). 0.5mg/ml in a 1:1 solution of DMSO:PBS, |
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Solubility in DMF | 2% in DMF |
Application | Detect β-galactosidase activity |
X-gal is commonly used in conjunction with IPTG for blue-white screening. |
5-Bromo-4-chloro-3-indolyl β-D-galactopyranoside is most commonly known asX-Gal. X-gal is a histochemical substrate for β-galactosidase which cleaves X-Gal to yield an insoluble blue precipitate.
X-Gal is a mainstay in molecular biology cloning applications in which it is used to detect the activity of β-galactosidase. X-Gal is used to detect the insertion of foreign DNA into the lacZ region of a plasmid DNA. Insertion of DNA into the lacZ region results in the loss of β-galactosidase activity. Bacteria cells that retain active β-galactosidase will result in characteristic blue colonies. Successful disruption of thelacZαgene disrupts the α-complementation of the β-galactosidase gene and the precipitate does not form, resulting in white colonies.
Many other applications also use X-Gal as a substrate to detect β-galactosidase activity. These include β-galactosidase -antibody linked immunoassays and immunohistochemistry, coliphage detection based on β-galactosidase induction and the detection of micrometastasis formation during tumor progession.
ebiomall.com






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1.CA15-3属于多形上皮黏蛋白。CA15-3测定广泛用于乳腺癌的辅助诊断。60%~80%进展期乳腺癌患者的CA15-3浓度大30kU/L。CA15-3有助于判断肿瘤的进展和疗效,测定值大于1000kU/L者预后不良。在乳腺癌初期其灵敏度较低,在Ⅲ期时约为12%,因此CA15-3测定不能用作乳腺癌的筛选手段.当怀疑乳腺癌而CA15-3又正常时,可以结合CEA值进行考虑。应注意到治疗后由于肿瘤细胞死亡,CA15-3起初会升高,然后才逐渐下降。持续不降或上升者则提示病情恶化。
2.其他恶性肿瘤,如肺、结肠、胰腺、肝脏、卵巢癌、子宫颈和子宫内膜的恶性肿瘤也都可见到CA15-3不同程度的阳性率(低于10%)。
3.肝硬化、肝炎、结节病、结核病、自身免疫性疾病(SLE)以及卵巢、乳腺的良性病变中,CA15-3值略高于正常范围,但阳性率一般低于10%,妊娠中后期,有近一半孕妇血清CA15-3升高。
核酸是天然高分子化合物,,糖类中的多糖(淀粉、纤维素、糖原等)也是天然高分子化合物
同属于生命的六大营养物质(水,无机盐,糖类,脂质,核酸,蛋白质)
还有如果用气相做糖的鉴别的话,需要样品量大不大?怎么衍生化?
不好意思,我是学药分的,对植化比较外行,请详细些,谢了先!
一般情况下同时测定蔗糖、果糖和葡萄糖。
选用哪种检测器呐。
本来经战友的意见已决定用示差了,但突然有个经销商愿意以比较优惠的价格卖蒸发光给我们,所以又开始犹豫了。
最后一次请教各位战友,如题目。谢谢!!

