
Description
PEG (Acetic Acid)2 (PEG di-acetic acid or PEG dicarboxyl) with superior quality specification of ≥95% Substitution.
PEG (Acetic Acid)2 from JenKem Technology is a homobifunctional PEG employed for amine pegylation and crosslinking, reactive towards the amine group of lysine(s). Homobifunctional PEG derivatives from JenKem Technology have numerous applications as crosslinkers for PEGylation of proteins and peptides, nanoparticle and surface modifications. Conjugation with homobifunctional PEGs ensures an increased drug load compared to pegylation with linear PEGs. JenKem Technology offers Acetic Acid PEG Acetic Acid with MW 2,000 Da (CM-PEG2000-CM), MW 3,500 Da (CM-PEG3500-CM), MW 5,000 Da (CM-PEG5000-CM), and MW 7,500 Da (CM-PEG7500-CM), in 1g and 5g packing sizes.
Different MW of PEG (Acetic Acid)2 may be available by custom synthesis, please email us at tech@jenkemusa.com for details on custom PEGs. JenKem Technology provides repackaging services for an additional fee, please contact us if you require a different package size than our catalog selection.
Bulk PEGs and GMP grade PEGs are made-to-order. Please contact us for bulk pricing.
Note: Starting July 2016, PEG (Acetic Acid)2 is the new name of the product Carboxyl PEG Carboxyl (MW 2000 Da (COOH-PEG2000-COOH), MW 3500 Da (COOH-PEG3500-COOH), MW 5,000 Da (COOH-PEG5000-COOH), and MW 7500 Da (COOH-PEG7500-COOH); or PEG Dicarboxyl. JenKem Technology has revised the name of the product to better reflect the chemical structure, as many other PEG derivatives with COOH group are offered in the catalog.
References:
- Wang, C., et al., Synthesis and formation mechanism of bone mineral, whitlockite nanocrystals in tri-solvent system, Journal of Colloid and Interface Science, 2020, V. 569, P. 1-11.
- Ji, F., et al., A Dual pH/Magnetic Responsive Nanocarrier Based on PEGylated Fe3O4 Nanoparticles for Doxorubicin Delivery, Journal of Nanoscience and Nanotechnology, 2018, 18.7: 4464-4470.
- Xiao, S., et al., Aptamer-mediated gene therapy enhanced antitumor activity against human hepatocellular carcinoma in vitro and in vivo, Journal of Controlled Release, 2017.
- Jing, P., et al, Enhanced growth inhibition of prostate cancer in vitro and in vivo by a recombinant adenovirus-mediated dual-aptamer modified drug delivery system, Cancer Letters, 2016, V. 383(2), P. 230-242.
- Lorenzo, M. M., et al., Homodimeric Protein–Polymer Conjugates via the Tetrazine–trans-Cyclooctene Ligation, Macromolecules, 2015.
- Xue, Y., et al., Quantifying thiol–gold interactions towards the efficient strength control, Nature communications, 2014, 5.
- Xu, P., et al., Hydrogen-bonded and reduction-responsive micelles loading atorvastatin for therapy of breast cancer metastasis. Biomaterials, 2014, 35(26): p. 7574-7587.
- Gajbhiye, V., et al., Drug-loaded nanoparticles induce gene expression in human pluripotent stem cell derivatives. Nanoscale, 2014, 6(1): p. 521-31.
- Gao, X., et al., Prostate stem cell antigen-targeted nanoparticles with dual functional properties: in vivo imaging and cancer chemotherapy. Int J Nanomedicine, 2012, 7: p. 4037-51.
Founded in 2001 by experts in PEG synthesis and PEGylation, JenKem Technology specializes exclusively in the development and manufacturing of high quality polyethylene glycol (PEG) products and derivatives, and related custom synthesis and PEGylation services. JenKem Technology is ISO 9001 and ISO 13485 certified, and adheres to ICH Q7A guidelines for GMP manufacture. The production of JenKem® PEGs is back-integrated to in-house polymerization from ethylene oxide, enabling facile traceability for regulated customers. JenKem Technology caters to the PEGylation needs of the pharmaceutical, biotechnology, medical device and diagnostics, and emerging chemical specialty markets, from laboratory scale through large commercial scale.
ebiomall.com






>
>
>
>
>
>
>
>
>
>
>
>
小弟有一中药处方,需要水煮醇沉处理,问下具体该怎么做,给我方子的老师去世了
告诉我中药先水煮,在用水煮醇沉法外敷治疗
给电话我直接问液可以
各位老师好,有做环黄芪醇的吗?其对心血管效果怎么样?使用剂量范围是不是很窄,我看文献,有报道,黄芪提取物对血管的作有是双向的,会不会在低剂量时对身体是有害的
完全醇水溶液如长期存放,会出现粘度增加甚至凝胶化的现象,聚合度和粘度越高,储存温度越低,越容易出现这种想象。可以采取以下措施:
(1)将聚乙烯醇水溶液重新加热搅拌即可恢复原来的流动性。
(2)添加硫氰盐酸盐(如钙、钠、铵等盐类)、苯酚、丁醇、山梨酸等可以有效防止凝胶化,添加量为5~10%。部分醇解型PVA长期存放不易产生粘度增加的情况。同时要注意长期存放容易发生发霉、腐化现象,需添加防霉、防腐剂。建议配置好水溶液后即时使用。
在本例中,溴处在间位,因此不参与反应。
而氯恰好处于对位,因而能发生反应,被甲氧基取代。
因此产物是4-硝基-2-溴苯甲醚。
各位亲,本人用70%乙醇回流提了中药大概70L,准备旋蒸浓缩但一直没浓缩,室温放了5天,之后要做药理试验的,会不会影响药效?需要重提吗?感谢感谢
(二)连接回流冷凝管时,冷凝管连接水不会对浸出物造成影响吗?
请求大神指点,不胜感激!
本人目前在做一个中药提取方法的研究,水提醇沉,醇沉浓度分别为50%、60%和70%,检验结果,得率分别为21.99%、23.85%和25.55%,但含量分别是33.48mg/g、16.60mg/g和19.42mg/g。理论上是醇沉浓度越高,去除的杂质越多,得率越低吗?含量是不是也应该是醇沉浓度越高含量越高?我的试验有什么问题,求各位大虾指点!
我想提取中药中的有效成分,好像目前醇提取的比较多,中药有比如黄柏,桑白皮这些。有谁知道醇提取步骤吗?能不能帮帮忙,万分感激
补充:
一般使用浓硫酸作催化剂,使醇类脱去羟基生成含双键的有机物。应注意的是醇发生消去反应时的温度控制,温度较低(140℃)时会生成副产物醚类,温度达到一定范围(170℃)时才会发生消去反应。消去反应的本质是羟基与β位上的一个H原子共同脱去生成H2O的反应,因而能发生消去反应的醇类必须要有β-H原子。
如果羟基相连接的碳的邻位碳有多个,且都有氢原子,则消去有氢原子较少的邻位碳上的氢原子。 示例:
乙醇发生消去反应的方程式
CH3CH2OH→CH2=CH2+H2O (条件为浓硫酸 170摄氏度)
求助战友们:
有做过中药醇提取,但是在收醇的时候,当浓缩至醇浓度约20%的时候,有析出现象,析出的还是我的有效成分,怎么才能解决这个问题呢?如果在未析出时停止浓缩,药液太稀,无法干燥呢?
问题1:我该如何浓缩定参数?
问题2:如果在未析出时放液,由于药液太稀,我该如何选择干燥方式?
求助站里的大侠们,谢谢!

